No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Muscle Soreness and Delayed-Onset Muscle Soreness
Abstract
Immediate and delayed-onset muscle soreness differ mainly in chronology of presentation. Both conditions share the same quality of pain, eliciting and relieving activities and a varying degree of functional deficits. There is no single mechanism for muscle soreness; instead, it is a culmination of 6 different mechanisms. The developing pathway of DOMS begins with microtrauma to muscles and then surrounding connective tissues. Microtrauma is then followed by an inflammatory process and subsequent shifts of fluid and electrolytes. Throughout the progression of these events, muscle spasms may be present, exacerbating the overall condition. There are a multitude of modalities to manage the associated symptoms of immediate soreness and DOMS. Outcomes of each modality seem to be as diverse as the modalities themselves. The judicious use of NSAIDs and continued exercise are suggested to be the most reliable methods and recommended. This review article and each study cited, however, represent just one part of the clinician's decisionmaking process. Careful affirmation of temporary deficits from muscle soreness is not to be taken lightly, nor is the advisement and medical management of muscle soreness prescribed by the clinician.
... However, there is conflicting evidence on the effectiveness of stretching. Some literature has determined that stretching prevents muscle soreness and delayed onset of muscle soreness through the rationale of viscoelastic and stressrelaxation behaviours of the muscle (23). In contrast, other literature determines low levels of evidence for the physical or physiological effects of stretching (16). ...
... The mean response of "physical" benefits of recovery was rated 0.45 higher on a Likert scale than the "physiological" benefits. However, it is known that the physiological performance of recovery directly affect the physical benefits achieved (23). For example, research has determined that the reduction of inflammation and swelling following exercise-induced muscle microtrauma improves muscle soreness and, therefore, increases muscular performance (23). ...
... However, it is known that the physiological performance of recovery directly affect the physical benefits achieved (23). For example, research has determined that the reduction of inflammation and swelling following exercise-induced muscle microtrauma improves muscle soreness and, therefore, increases muscular performance (23). Although players rated 'Reduces muscle spasm, tightness and/or soreness' the highest, 'reduces swelling and/or inflammation' was rated the lowest physiological benefit. ...
Youth field hockey exhibits elevated injury rates, potentially attributed to insufficient training, limited injury prevention
awareness, and resource constraints for players and coaches. Furthermore, a connection exists between inadequate
sports recovery practices and sports-related injuries. This study represents the inaugural exploration in New Zealand
into the utilisation, beliefs, obstacles, and perspectives regarding sports recovery among youth field hockey participants
throughout a typical season. A survey was conducted involving 119 participants, comprising 73 females (average age
= 17.07 ± 0.98 years; average years of playing = 10 ± 3.06) and 46 males (average age = 17.28 ± 0.97 years; average
years of playing = 7.98 ± 3.32). Participants completed a 22-item online questionnaire. Nearly half (47%) played at a
representative level, while 52% engaged at a recreational level. The questionnaire encompassed inquiries about their
adoption of recovery strategies, perceived hindrances, and comprehension of sports recovery. Data were analysed
using Excel and presented as percentages, means ± standard deviation (SD), or median ± interquartile range (IQR).
Among the findings, 52% of players incorporated sports recovery practices, with stretching being the most prevalent
(93%), regarded as beneficial by 51%. Tissue release techniques and active land-based strategies were utilized by 73%
of players, cold water immersion by 41%, and contrast water therapy by 15%. Time constraints and limited knowledge
were commonly cited as barriers to recovery practices. Athletes primarily valued physical benefits, such as injury
prevention, performance enhancement, and reduced muscle tightness. Given their reported constraints, this study
underscores the potential need for targeted education on sports recovery for New Zealand's youth field hockey players.
It also sheds light on the prevalence and preferred strategies among these athletes.
... These eccentric movements induce mechanical stress and fatigue within the muscle fibers [1][2][3] . The strain on the sarcomere during eccentric exercises triggers an inflammatory response, leading to the Open Access accumulation of cytokines that amplify the perception of pain 4 . The most prominent symptom of DOMS is muscle soreness/tenderness, which may interfere with range of motion or activities of daily living [1][2][3][4] . ...
... The strain on the sarcomere during eccentric exercises triggers an inflammatory response, leading to the Open Access accumulation of cytokines that amplify the perception of pain 4 . The most prominent symptom of DOMS is muscle soreness/tenderness, which may interfere with range of motion or activities of daily living [1][2][3][4] . Other symptoms include elevated creatine kinase levels, heightened cytokine response, joint stiffness, and reduced muscular strength 4 . ...
... The most prominent symptom of DOMS is muscle soreness/tenderness, which may interfere with range of motion or activities of daily living [1][2][3][4] . Other symptoms include elevated creatine kinase levels, heightened cytokine response, joint stiffness, and reduced muscular strength 4 . The onset of DOMS typically occurs within 6-12 hours following eccentric exercise and progressively intensifies, reaching peak pain levels between the 48 to 72-hour mark 1 . ...
Introduction: The purpose of this investigation was to determine the effects of a novel dietary supplement (Maltor™) on indices of muscle recovery after a delayed-onset muscle soreness (DOMS) protocol. Methods: In a double-blind, placebo-controlled, crossover trial, subjects consumed the treatment (i.e., 5 g. Maltor™ – a complex of taurine and L-malic acid in an approximately 2:1 ratio) and placebo (i.e.,1 g of sodium citrate and 4 g of maltodextrin) daily over 14 days. Subjects were instructed to consume the treatment or placebo for 14 days. After 14 days of consumption, subjects performed a DOMS protocol based on their 1-RM. Inflammatory markers, arm circumference, strength, subjective and objective measures of pain were assessed 24hr, 48hr and 72hrs after DOMS protocol. Results: A statistically significant difference was found for the assessment of pain threshold via the pressure algometer (p=0.5). Subjects in the treatment group exhibited a higher pain threshold two days post-DOMS (i.e., delta score data). We found no significant differences between groups for arm circumference, 1-RM (p=0.66), pain assessed by VAS (0.94), or arm circumference (p=0.91) between the groups. Furthermore, there were no significant differences between groups for Interleukin-6 (p=0.85) and C-reactive protein (p=0.48), key markers of inflammation. Conclusions: Based on this preliminary investigation, two weeks of consuming taurine-L-malic acid complex may diminish delayed-onset muscle soreness in exercise-trained males as assessed by an algometer (i.e., assessment of pain threshold).
... Under this precept, the World Health Organization recommends a minimum of 150-300 min of aerobic physical activity per week, along with muscle-strengthening activities of moderate intensity for at least two days per week (Bull et al., 2020). However, adherence to these recommendations would require sedentary people to engage in physical activity they are not used to (Park et al., 2020), including unaccustomed exercises and eccentric contractions, which increase the chance of developing delayed-onset muscle soreness (DOMS) (Hody et al., 2019;Lewis et al., 2012). Better understanding on the effects of DOMS on pain perception, muscle function, and other relevant variables over a specific time period could potentially improve future interventions for preventing, managing, and mitigating its effects. ...
... For instance, repeated eccentric contractions and unaccustomed sporting activities, can cause mechanical damage of muscle tissue, protein degradation, autophagy, and trigger a local inflammatory response (Hotfiel et al., 2018). Clinical signs of EIMD may include local muscular tenderness and swelling as well as a reduction in force production and range of motion, while clinical symptoms vary from aching pain to muscle stiffness (Kim and Lee, 2014;Lewis et al., 2012). The clinical presentation varies among individuals, although for most, DOMS typically begins approximately 6-12 h post-exercise, rapidly peaks at 24-48 h, and gradually subsides within 5-7 days (Hotfiel et al., 2018). ...
... A peak reduction of 25% in maximal isometric strength of the knee flexor muscles was observed 48 h after baseline, indicating moderate exercise-induced muscle damage (Paulsen et al., 2012). In this respect, it is important to consider that muscle contraction is centrally inhibited when activated in parallel with a pain response (Graven-Nielsen et al., 2002), yielding a lower strength performance (Kim and Lee, 2014;Lewis et al., 2012). Therefore, muscle damage can probably only to some degree be the reason for the reduction seen here where pain inhibition likely also contributed. ...
Background:
Delayed-onset muscle soreness (DOMS) is common after unaccustomed exercises and can restrict performance if intense physical activities are performed while the muscle is still sore. This study aimed to evaluate the recovery process following exercise-induced DOMS over a seven-day period by evaluating sensory, functional, and electromyographic parameters.
Methods:
Twenty-four healthy males participated in four experimental sessions (Day-0, Day-2, Day-4, Day-7). Pain perception, pressure pain sensitivity, active range of motion, maximal isometric strength, and muscle activity of the hamstrings during the maximal isometric contraction were assessed bilaterally at each session. A single-leg deadlift eccentric exercise (5-sets of 20-reps) was performed at the end of Day-0 to induce DOMS in the dominant leg.
Findings:
At Day-2, the DOMS-side showed increased pain sensitivity and decreased active range of motion, strength and muscle activity compared to Day-0 (P < 0.015). Muscle activity on the DOMS-side reached similar values than at baseline on Day-4, whereas pain perception, pressure pain sensitivity, maximal isometric strength, and active range of motion had returned to the baseline state on Day-7. No changes over time were observed on the control-side, showing all variables an excellent reliability between values at Day-0 and Day-7 (Intraclass Correlation Coefficient > 0.90).
Interpretation:
Surface electromyographic values during a maximal isometric contraction recover faster than the other parameters. Given the heterogeneous path of altered variables towards DOMS recovery, trainers and clinicians should consider a multimodal assessment, including quantitative sensory and functional measures in addition to the subjective perception of recovery.
... The International Association for the Study of Pain defines pain as "An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage". 1 Relatively, soreness is another familiar somatosensation that predominantly occurs in the musculoskeletal regions. 2 In most cases, soreness manifests after intense exercise and negatively interferes with daily activities. [2][3][4][5][6] Acute-onset soreness after exercise is associated with acute lactate accumulation, and musculoskeletal micro-injury results in delayed onset muscle soreness (DOMS). [2][3][4][5][6] Despite its common occurrence after physical activity, soreness sensation is not exclusive to exercise but also occurs in disease conditions not related to WHAT IS ALREADY KNOWN ON THIS TOPIC ⇒ Soreness is a common somatic complaint of the musculoskeletal regions and negatively interferes with quality of life. ...
... [2][3][4][5][6] Acute-onset soreness after exercise is associated with acute lactate accumulation, and musculoskeletal micro-injury results in delayed onset muscle soreness (DOMS). [2][3][4][5][6] Despite its common occurrence after physical activity, soreness sensation is not exclusive to exercise but also occurs in disease conditions not related to WHAT IS ALREADY KNOWN ON THIS TOPIC ⇒ Soreness is a common somatic complaint of the musculoskeletal regions and negatively interferes with quality of life. ⇒ Whether soreness symptoms manifest in musculoskeletal pain disorders, such as fibromyalgia (FM), remains less investigated. ...
... Muscle soreness results in intolerance to daily activity and thus hinders individuals from daily activities or rehabilitation. 6 In research of soreness, post-exercise soreness is mostly investigated, including acute post-exercise soreness and DOMS. 6 The morbid soreness in FM shows several similarities as post-exercise conditions. ...
Objectives
Muscle soreness occurs after exercise and also in musculoskeletal diseases, such as fibromyalgia (FM). However, the nosography and pathoetiology of morbid soreness in FM remain unknown. This study aimed to investigate the morbid soreness of FM, evaluate its therapeutic responses and probe its pathophysiology with metabolomics profiling.
Methods
Patients with newly diagnosed FM were prospectively recruited and completed self-report questionnaires pertaining to musculoskeletal symptoms. The phenotypes and metabotypes were assessed with variance, classification and correlation analyses.
Results
Fifty-one patients and 41 healthy controls were included. Soreness symptoms were prevalent in FM individuals (92.2%). In terms of manifestations and metabolomic features, phenotypes diverged between patients with mixed pain and soreness symptoms (FM-PS) and those with pain dominant symptoms. Conventional treatment for FM did not ameliorate soreness severity despite its efficacy on pain. Moreover, despite the salient therapeutic efficacy on pain relief in FM-PS cases, conventional treatment did not improve their general disease severity. Metabolomics analyses suggested oxidative metabolism dysregulation in FM, and high malondialdehyde level indicated excessive oxidative stress in FM individuals as compared with controls (p=0.009). Contrary to exercise-induced soreness, lactate levels were significantly lower in FM individuals than controls, especially in FM-PS. Moreover, FM-PS cases exclusively featured increased malondialdehyde level (p=0.008) and a correlative trend between malondialdehyde expression and soreness intensity (r=0.337, p=0.086).
Conclusions
Morbid soreness symptoms were prevalent in FM, with the presentation and therapeutic responses different from FM pain conditions. Oxidative stress rather than lactate accumulation involved phenotype modulation of the morbid soreness in FM.
Trial registration number
NCT04832100 .
... Delayed onset muscle soreness (DOMS) refers to the phenomenon of muscle soreness caused by micro-damage of muscle cell structure following eccentric exercise or unaccustomed high-intensity exercise, which traditionally peaks at 24-72 hours [1][2][3]. In addition to localized muscle pain, symptoms of DOMS may include swelling, joint stiffness, reduced joint range of motion, and reduced muscle strength, all of which can seriously affect athletic training [4]. ...
... As shown in Fig. 2, there was no significant difference of interleukin 6 in the C, CWT and CWI group at B (F (2,27) ...
... As shown in Fig. 3, there was no significant difference of prostaglandin-2 in the C, CWT and CWI group at B (F (2,27) ...
Background: This study aimed to investigate the effects of cold water immersion (CWI) and contrast water therapy (CWT) on serum interleukin 6 and prostaglandin 2 levels in self-perceived exertion, and muscle soreness of elite race walkers over a 15-day high-intensity training period. Methods: Thirty elite male race walkers were randomly divided into three groups: control group (C, n = 10), cold-water immersion (CWI, n = 10) group, contrast water therapy (CWT, n = 10) group. After daily training, elite race walkers were exposed to either CWI (10 minutes at 10 °C) or CWT (4 cycles of 2.5 minutes, alternately at 12 °C and 38 °C). Elite race walkers in the control group only performed simple stretching without any additional treatment. The serum interleukin 6, prostaglandin 2, self-perceived exertion, and muscle soreness were tested at 6 training points at baseline (B), light load-1 (L1), heavy load-1 (H1), medium load (M), heavy load-2 (H2), light load-2 (L2), respectively. Results: When compared with the CWT group, the interleukin 6 level, prostaglandin 2 level, self-perceived exertion, and muscle soreness of the C group were not significantly different. When compared with the CWT group, the interleukin 6 level in the CWI group was significantly lower at the time point of L1 and H2. Similarly, CWI significantly reduced the prostaglandin 2 levels at M and L2, except for H2. Self-perceived exertion and muscle soreness were not significantly different in both groups. Conclusions: The results from this study demonstrate that CWI may be more effective than CWT for reducing inflammatory markers at certain points in a training cycle, but it does appear that this effect can be induced in a predictable fashion.
... EIMD disrupts sarcomeres, other cytoskeletal elements, cell membranes, and impairs the excitationcontraction coupling system [25]. This disruption negatively impacts the muscle function and leads to three remarkable features (a) decrease in muscle performance; (b) delayed onset of muscle soreness (DOMS); and (c) an increase in the concentration of intramuscular enzymes in blood plasma, such as Creatine Kinase (CK) [14,23,25]. ...
... DOMS is defined as a delayed feeling of soreness (about 24H after the exercise) accompanied by muscle stiffness, aching soreness, and/or muscular tenderness [14]. Muscle soreness peaks within 72H and slowly resolve within 5 to 7 days [14]. ...
... DOMS is defined as a delayed feeling of soreness (about 24H after the exercise) accompanied by muscle stiffness, aching soreness, and/or muscular tenderness [14]. Muscle soreness peaks within 72H and slowly resolve within 5 to 7 days [14]. DOMS was assessed by the VAS of 10 degrees, ranging from "no soreness" (0) to "severe soreness" [9] [27]. ...
Purpose:
The purpose of the study is to compare the effects of total cold-water immersion to ice massage on muscle damage, performance, and delayed onset of muscle soreness.
Methods:
Sixty participants were randomized into two groups where they completed a muscle damage protocol. Afterward, muscle damage, muscle performance, and delayed onset muscle soreness were respectively measured by serum Creatine Kinase (CK) test, one-repetition maximum (1-RM) test, countermovement jump (CMJ) test, and visual analog scale (VAS). The measurements were taken at five different timelines (Baseline, 2 H, 24 H, 48 H, and 72 H).
Results:
Data showed that values of all within-group measures of the dependent variables had extremely significant statistical differences (p < 0.001) for both intervention groups. Serum CK values peaked at 24 H for both groups. At 72 H, serum CK values dropped to baseline values in the total cold-water immersion group, while remaining high in the ice massage group. At 72 H, the values of the 1-RM test, CMJ test, and VAS approximated baseline values only in the total cold-water immersion group (p < 0.001).
Conclusions:
Total cold-water immersion (TCWI) was more effective when compared to ice massage (IM) on improving values of recovery from exercise-induced muscle damage (EIMD). Hence, this modality may be considered during athletic recovery to maximize athletic performance.
Clinical trial registration:
This trial was registered in ClinicalTrials.gov under the trial registration number ( NCT04183816 ).
... Intense exercise, training and competition can induce tissue vibrations [60] and eccentric contractions [61], possibly leading to muscle damage [4], with a consequent temporary reduction in muscular force [62,63] and decreased physical performance [63,64]. At the same time, an increased tissue inflammation [60][61][62][63][64][65][66], perceived fatigue [61], pain [62,63], delayed onset of muscle soreness (DOMS) [64], and/or increased risk of injury [66][67][68] may occur. ...
... Intense exercise, training and competition can induce tissue vibrations [60] and eccentric contractions [61], possibly leading to muscle damage [4], with a consequent temporary reduction in muscular force [62,63] and decreased physical performance [63,64]. At the same time, an increased tissue inflammation [60][61][62][63][64][65][66], perceived fatigue [61], pain [62,63], delayed onset of muscle soreness (DOMS) [64], and/or increased risk of injury [66][67][68] may occur. ...
Intense, long exercise can increase oxidative stress, leading to higher levels of inflammatory mediators and muscle damage. At the same time, fatigue has been suggested as one of the factors giving rise to delayed-onset muscle soreness (DOMS). The aim of this study was to investigate the efficacy of a specific electrical stimulation (ES) treatment (without elicited muscular contraction) on two different scenarios: in the laboratory on eleven healthy volunteers (56.45 ± 4.87 years) after upper limbs eccentric exercise (Study 1) and in the field on fourteen ultra-endurance athletes (age 47.4 ± 10.2 year) after an ultra-running race (134 km, altitude difference of 10,970 m+) by lower exercising limbs (Study 2). Subjects were randomly assigned to two experimental tasks in cross-over: Active or Sham ES treatments. The ES efficacy was assessed by monitoring the oxy-inflammation status: Reactive Oxygen Species production, total antioxidant capacity, IL-6 cytokine levels, and lactate with micro-invasive measurements (capillary blood, urine) and scales for fatigue and recovery assessments. No significant differences (p > 0.05) were found in the time course of recovery and/or pre–post-race between Sham and Active groups in both study conditions. A subjective positive role of sham stimulation (VAS scores for muscle pain assessment) was reported. In conclusion, the effectiveness of ES in treating DOMS and its effects on muscle recovery remain still unclear.
... 19 Nutritional interventions and muscle soreness and delayed onset of muscle soreness Muscle soreness is characterized by muscular tenderness, aching pain, and/or muscle stiffness perceived by athletes during or immediately after exercise. 49 Delayed onset of muscle soreness shares similar intensity and quality to MS; however, it starts usually within 24 hours after the exercise session and resolves in 5 to 7 days. 49 So far, over 6 hypotheses have been suggested for the underlying mechanism of MS and DOMS-namely, enzyme efflux, inflammation, muscle damage, connective tissue damage, muscle spasm, and lactic acid theories. ...
... 49 Delayed onset of muscle soreness shares similar intensity and quality to MS; however, it starts usually within 24 hours after the exercise session and resolves in 5 to 7 days. 49 So far, over 6 hypotheses have been suggested for the underlying mechanism of MS and DOMS-namely, enzyme efflux, inflammation, muscle damage, connective tissue damage, muscle spasm, and lactic acid theories. 50 Findings provided evidence of significant efficacy for BCAAs and leaf extract with a moderate level of evidence and omega-3 with a low level of evidence on DOMS. ...
Context:
Several meta-analyses have been conducted on the effect of nutritional interventions on various factors related to muscle damage. However, the strength of the evidence and its clinical significance are unclear.
Objectives:
This umbrella review aimed to provide an evidence-based overview of nutritional interventions for exercise-induced muscle damage (EIMD).
Data sources:
PubMed, Scopus, and ISI Web of Science were systematically searched up to May 2022.
Data extraction:
Systematic reviews and meta-analyses of randomized controlled trials investigating nutritional interventions' effects on recovery following EIMD were included. The certainty of the evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE).
Results:
Fifty-three randomized controlled trial meta-analyses were included, evaluating 24 nutritional interventions on 10 different outcomes. The results revealed a significant effect of hydroxymethylbutyrate (HMB) supplementation and l-carnitine supplementation for reducing postexercise creatine kinase; HMB supplementation for reducing lactate dehydrogenase; branched-chain amino acids and leaf extract supplementation for reducing the delayed onset of muscle soreness; and l-carnitine, curcumin, ginseng, polyphenols, and anthocyanins for reducing muscle soreness, all with moderate certainty of evidence.
Conclusions:
Supplementation with HMB, l-carnitine, branched-chain amino acids, curcumin, ginseng, leaf extract, polyphenols, and anthocyanins showed favorable effects on some EIMD-related outcomes.
Protocol registration:
PROSPERO registration no. CRD42022352565.
... 33 It is thought to be caused by microtrauma to muscle, followed by an inflammatory process of the muscle fibres, predominantly secondary to highintensity eccentric muscle contractions. 33,34 According to the BAMIC, DOMS represents a grade 0 b injury, characterized by the presence of generalized, feathery intramuscular oedema on fluid sensitive MRI sequences, affecting several muscles. 23 Exercise-related signal abnormalities ...
The quadriceps muscles are a large group of four muscles in the anterior compartment of the thigh, comprising the rectus femoris, vastus medialis, vastus intermedius and vastus lateralis, which in combination act as the primary extensors of the knee joint. The rectus femoris is also responsible for hip joint flexion. Quadriceps muscle injuries are frequently encountered in sports and athletic activities, and present a significant challenge in the realm of sports medicine, impacting athletes across various disciplines and levels of competition. A spectrum of sporting injuries and imaging findings can affect this muscle group, including strains and tears, avulsions, contusions, degloving injuries, and exercise related signal abnormalities (ERSA). A thorough understanding of these various pathologies and imaging features is crucial to guide appropriate diagnosis, management and rehabilitation, as well as ensure safe and prompt return to play, minimise risk of re-injury or long term adverse sequela, optimise performance and improve career longevity of these athletes. This comprehensive review article aims to review the unique anatomy of the quadriceps muscle group and integrate current knowledge of the various forms of sporting injuries affecting it, with a specific emphasis on the imaging features.
... Clarke et al. (2024) evaluated the effect of massage gun therapy on physical and perceptual recovery in 65 active adults. Based on the results, percussion massage guns combine massage and vibration therapy, allowing for more intense muscle tissue movement and stimulation of mechanoreceptors [35,36]. The protocol of the present study was prepared according to the results of previous research previous research although contradictory results were obtained for the massage gun group. ...
Introduction: Myofascial pain syndrome is a common musculoskeletal injury, especially among athletes, typically treated with symptomatic invasive and non-invasive methods. This study compares the effects of massage guns and radial extracorporeal shock wave therapies on myofascial pain syndrome symptoms in amateur athletes. Materials and Methods: In this clinical trial, 45 amateur athletes (18-30 years old) were recruited, who were randomly assigned to 15-member groups of shock wave, massage gun, and control (routine treatment included electrotherapy and stretching, which was applied on three groups). After initial evaluations of the pain intensity, pain pressure threshold (PPT), isometric muscle strength, and range of motion (ROM), the patients received single-session treatment and were immediately reassessed. Results: The results showed pain relief and improved PPT following shock wave plus routine treatment (P=0.03). The control group had less pain, while pain intensity and PPT did not change. The variables were not significantly different between the groups (P=0.12). Shock wave along with routine treatment increased plantar flexion ROM (P=0.00), unlike the massage gun. Additionally, dorsiflexion ROM (P=0.63) and maximal isometric gastrocnemius muscle strength (P=0.95) remained unchanged in all groups. Conclusion: One session of massage gun therapy immediately reduced gastrocnemius muscle pain, while it failed to change PPT, maximal isometric gastrocnemius muscle strength, or dorsiflexion and plantar flexion ROM. However, shock wave therapy immediately increased plantar flexion ROM and PPT, and reduced pain intensity. These modalities led to limited changes, suggesting the need for repeated sessions and supplementary treatments.
... Several previous studies have shown that there is a correlation between the incidence of DOMS and muscle damage due to exercise and sports activities (Amalraj et al., 2020;McFarlin et al., 2016;Nakhostin-Roohi et al., 2016;Sulistyarto et al., 2022). Eccentric training can result in DOMS resulting in impairment or a large decrease in strength and can last 5 -7 days, with conditions peaking 24-48 hours after exercise (Konrad et al., 2022;Lewis et al., 2012;da Silva et al., 2018). Delayed-onset muscle pain (DOMS) is a multifactorial process associated with muscle pain, stiffness, swelling, tenderness, altered joint kinematics, muscle fiber disorders, acute tissue damage, and decreased strength and strength. ...
Delayed Onset Muscle Soreness (DOMS) is a pain that occurs after uncustomized eccentric exercise and can happen to anyone, both those who are athletes and other individuals. DOMS is usually felt 24-72 hours after exercise or activities that use eccentric movements, which interfere with the athlete’s training activities and other individuals’ daily activities. This study aimed to determine the effectiveness of kencur extract supplementation (kaempferia galanga linn) on DOMS and creatine kinase (CK) plasma levels after eccentric exercise. This research is quasi-experimental, using a randomized control group design as the design in this study. Research subjects (n = 28) were randomly divided into 2 groups, namely the kencur extract group (200 mg/day) and the placebo group (corn flour). The supplementation process in both groups was carried out for 5 days (3 days before and 2 days after) the eccentric exercise. DOMS pain (VAS) and blood samples (CK plasma) were taken 24 hours (pre) and 48 hours (post) after eccentric exercise. The destructive drill uses the 5 x 20 Eccentric depth jump drill. The data obtained in the form of changes in DOMS pain and CK plasma were then analyzed using ANOVA with sig. 0.005. Supplementation of galingale extract was effective in reducing DOMS pain with p = 0.008 (0.05) and CK plasma value p = 0.000 (0.05) compared to placebo after eccentric exercise. Supplementation of galingale extract (Kaempferia Galanga Linn) for 5 days is effective as an effort to reduce the risk of DOMS pain sensation and reduce the increase in muscle damage with CK as a marker after eccentric exercise.
... EIMD results in muscle inflammation, which could lead to delayed onset muscle soreness (DOMS) (Cheung et al., 2003). DOMS is associated with muscle tenderness, reduced range of motion, stiffness, and swelling (Lewis et al., 2012). Quantifying EIMD and DOMS is helpful for training planning and recovery assessment (Hotfiel et al., 2018;Mujika, 2017). ...
Skin temperature responses have been advocated to indicate exercise-induced muscle soreness and recovery status. While the evidence is contradictory, we hypothesize that the presence of muscle damage and the time window of measurement are confounding factors in the skin temperature response. The objective was to determine whether skin temperature is influenced by different workloads and the time course of temperature measurements over the following 24 h. 24 trained male military were assigned to one of three groups: GC group (n = 8) serving as control not performing exercises, GE group (n = 8) performing a simulated military combat protocol in an exercise track with different obstacles but designed not to elicit muscle damage, and the GEMD group (n = 8) performing the simulated military combat protocol plus 5 sets of 20 drop jumps, with 10-sec between repetitions and with 2-min of rest between sets aiming to induce muscle damage. Skin temperature was measured using infrared thermography before exercise (Pre) and 4 (Post4h), 8 (Post8h) and 24h (Post24h) post-exercise. Perception of pain (DOMS) was evaluated Pre, Post24h, and Post48h, and countermovement jump height was evaluated at Pre and Post24h. DOMS did not differ between groups in the Pre and Post24h measures but GEMD presented higher DOMS than the other groups at Post48h (p < 0.001 and large effect size). Jump height did not differ for GEMD and GC, and GE presented higher jump height at Post24h than GC (p = 0.02 and large effect size). Skin temperature responses of GEMD and GG were similar in all measurement moments (p > 0.22), and GE presented higher skin temperature than the GC and the GEMD groups at Post24h (p < 0.01 and large effect sizes). In conclusion, although physical exercise elicits higher skin temperature that lasts up to 24 h following the efforts, muscle soreness depresses this response.
... exercise, or connective tissue damage [2][3][4][5] . It's important to note that DOMS is a natural part of the adaptation process, especially when muscles are subjected to new types of exercise. ...
Introduction: The purpose of this investigation was to determine the effects of multi-ingredient dietary supplement on indices of muscle recovery on delayed-onset muscle soreness (DOMS). Methods: In a randomized, placebo-controlled trial, healthy exercise-trained subjects (n=24) consumed the treatment (i.e., Caraflame®: Retinyl Palmitate (Vit. A) 3.3 mg, Sodium Butyrate 175 mg, and Beta-Caryophyllene 30 mg or placebo (i.e., Maltodextrin 1000mg) daily over a 14-day period. Subjects completed the DOMS protocol and were assessed for changes in pain (visual analog scale (VAS) and a pressure algometer), strength (1-RM), and inflammatory markers (Interleukin-1b, Interleukin-6 and C-reactive protein). A dependent samples t-test was used to determine differences between groups with regard to the delta score. A p-value of P<0.05 was used to determine significance. Results: All subjects were physically active, healthy adults (Mean±SD – Age 23.5±7, Height 170±12.7 cm, Body Mass 71.0±19.57 kg, % body fat 24.3±10.6). A statistically significant difference was found for the assessment of pain threshold via VAS. Subjects in the treatment group exhibited a higher pain threshold two days post-DOMS (i.e., delta score data). No significant differences between groups for arm circumference, 1-RM, pain assessed by algometer, or arm circumference between the groups. Furthermore, there were no significant differences between groups for inflammatory markers (CRP, IL-6, and IL-1b). Conclusions: Based on this preliminary investigation, two weeks of a multi-ingredient dietary supplement may decrease the subjective perception of delayed-onset muscle soreness in exercise-trained adults.
... DOMS begins with the process of muscle contraction/injury with tension on the functional unit of the muscle, the sarcomere, damage thereto, accumulation of intracellular calcium, increased demands on the connective tissue and inflammatory response with the recruitment of inflammatory cells and cytokines that enhance pain perception and nerve endings; and the main characteristic is the sensation of discomfort in the skeletal muscles as a result of physical exercise performed hours before, with a certain overload that the body is not used to performing. (Tricoli, 2001;Lewis, Ruby, & Bush-Joseph, 2012) Despite being a widely studied theme, the results are still inconclusive. Studies have shown that BC can be an effective method for post-exercise recovery (Knight, 2000;Gregson et al., 2011). ...
Objective: To investigate the subacute influence of the use of body cooling by immersion in cold water on the perception of Delayed Muscle Pain (DOMS), in the posterior leg muscles, 24, 48 and 72 hours after carrying out a three-course muscle fatigue protocol. series of repetitions until concentric failure of the bilateral plantar flexion and dorsiflexion movement. Methods: 22 untrained participants (age: 20.4±1.7 years; body mass: 65.91±15.38kg; height: 166.86±8.47cm) participated in an effort protocol that consisted of three sets of repetitions until concentric failure of the leg muscles, of plantar flexion and bilateral dorsiflexion movement, with one's own body weight. After one minute, through a draw, one of the legs was designated for immersion, up to the height of the popliteal fold, in a vat of ice water (between 12 and 14º C), during three stages of 5 minutes with a 1 minute break between each stage, totaling 15 minutes of immersion. At the same time, the other leg remained in passive recovery, serving as control. After 24, 48 and 72 hours, the individuals were evaluated regarding the perception of DOMS, in both legs, with an analog pressure algometer (pressure of 6kgf/cm²). The perception of pain was signaled by the participants using the Pain Visual Analogue Scale (VAS). Results and conclusions: No statistically significant differences (p<0.05) were found between body cooling and passive recovery, in both groups, in the assessment of perception of DOMS 24, 48 and 72 hours after the exercise protocol.
Keywords: Cold-water immersion. Muscle damage. Injuries. Post-exercise recovery.
... Oxidative stress related to physical exercise can also lead to muscle fatigue and, consequently, reduced athletic performance and recovery. Compared to Omnivores, VOLUME 2 | ISSUE 1 | 2024 | 51 people who follow a Vegan diet have an increased consumption of antioxidants, which has been shown to be effective in reducing oxidative stress associated with exercise (Lewis, Ruby and Bush-Joseph, 2012). ...
Being healthy is a prerequisite for becoming a successful athlete. Most scientific evidence strongly associates a well-planned Vegan diet with health, successful body weight control, a preventive measure and, in some cases, the end and reversal of some of the most common noncommunicable chronic diseases. However, despite the solid health benefits of these diets, Vegan athletes are often confronted with prejudices for unfounded doubts and motives. Through the analysis of existing literature, the objectives of the present study were to explore the various advantages and risks of the Vegan diet for the health of sportsmen and women, whether in the context of competition or not and analyse the influence of this type of diet on the sports performance of athletes, when compared to omnivorous athletes. As can be seen, the literature on this topic is quite scarce and, apparently, performance is not boosted depending on the type of diet adopted. With this knowledge intended to demonstrate that vegan diets are compatible with sports performance, thus being able to encourage athletes and their families, coaches and health and sports experts to have a more open mind when an athlete expresses their desire to adopt a Vegan diet.
... However, according to current literature, the underlying mechanism of DOMS is not completely understood, but it has been identified that the microtrauma to the muscle fibers, which then leads to inflammation plays a critical role 1,3 . Additionally, the intensity and duration of the eccentric activity also play an important role in the extent of symptoms associated with delayed onset muscle soreness 4,5 . When an individual performs an activity at an unfamiliar intensity or duration, the potential of the muscle experiencing DOMS becomes more likely. ...
Introduction: Delayed onset muscle soreness (DOMS) is a common condition characterized by muscle stiffness, pain, and inflammation following intense or unaccustomed exercise. Despite its prevalence, the underlying mechanisms of DOMS remain unclear. This study aimed to investigate the effects of collagen supplementation on tissue repair and pain associated with DOMS in exercise-trained individuals. Methods: Fourteen exercise-trained men (n=7) and women (n=7) were enrolled in a randomized, counterbalanced, crossover trial. Participants were assigned to either a whey protein group (n=8) or a collagen protein group (n=6). Each participant consumed 40g of their respective protein supplement daily for four consecutive days. Peak soreness was assessed using self-reported ratings and algometer measurements. Statistical analysis included independent samples t-tests and Levene's test for equality of variances. Results: The analysis revealed no significant difference in peak soreness between the whey protein and collagen protein groups at the 24-hour time point (t(12) = 1.33, p = 0.208). Both groups experienced a decrease in peak soreness over the 24-hour period, but the reduction was not statistically different between the groups. No significant differences were observed in other variables measured. Conclusions: These findings suggest that collagen protein supplementation did not significantly reduce peak soreness associated with DOMS compared to whey protein supplementation in exercise-trained individuals. While collagen supplementation has shown potential benefits in tissue repair and joint health, further research is needed to explore its specific effects on DOMS. Larger studies with different dosages and participant populations are warranted to obtain a more comprehensive understanding of collagen's impact on muscle soreness and tissue repair.
... For example, especially if vigorous, exercise may be associated with fatigue and body ache that can persist into the next day; in some, delayed-onset muscle soreness (the DOMS syndrome) may uncommonly occur. 50 If performed without sufficient warming up, or if incorrectly performed, or if performed using unsuitable shoes and gear, or if performed using unsuitable or defective equipment, or if warning physiological signals are ignored, or if the exerciser pushes beyond accustomed limits, exercise can result in musculoskeletal and other injuries, not all of which are reversible. ...
Regular physical activity in any form is important for health; nevertheless, more than a quarter of adults and more than four-fifths of adolescents do not meet recommended thresholds for exercise. This article outlines the magnitude of the global problem. It discusses terms such as physical activity, aerobic exercise, muscle strengthening exercise, weight-bearing exercise, sitting time, and sedentariness. It presents and explains current guidance on physical activity, averaged across a week, for adults as well as special populations, including adolescents, the elderly, and pregnant women. It notes that immediate, short-term, and long-term benefits of exercise have been identified in thousands of randomized controlled trials (RCTs) and cohort studies, and pooled in hundreds of meta-analyses, for a wide range of neuropsychiatric and medical conditions. It explains the strengths and limitations of the RCT and cohort study data as well as explains how some of the limitations can and have been addressed. It demonstrates how the Bradford Hill criteria can be applied to support the credibility of the research findings. It outlines immediate as well as long-term risks associated with exercise, as well as factors associated with these risks. In summary, the benefits of exercise outweigh the harms, especially when exercise is performed in moderation and within the individual's comfort zone. Although any physical activity is better than none, individuals should attempt to reach the currently recommended thresholds for exercise. There is little additional benefit associated with exceeding the guidance, and there may be immediate as well as long-term risks associated with overexercising. Finally, sitting time and sedentariness are constructs that are independent of physical activity; greater sitting time and greater sedentariness are both associated with poorer health outcomes and should therefore be discouraged at the same time that physical activity is encouraged.
... 30,31 Delayed onset muscle soreness after HIE might be the reason for poor SSQ the next morning. 62,63 In contrast to Aloulou et al and Arias et al, some studies revealed that SSQ was not affected after acute evening LIE, MIE and HIE compared to no exercise. 11,20,36 Compared with no exercise, acute evening MIE and HIE did not negatively affect subjective TST and WASO. ...
The effects of different intensities of evening exercise on subsequent sleep remain contradictory. Thus, this systematic review and network meta-analysis aimed to compare and rank the effects of different intensities of acute evening exercise on sleep in healthy adults with good sleep. Articles were systematically searched journals indexed in the PubMed, Web of Science, Cochrane Library, Embase, and Scopus databases from inception to the 5th of May, 2022. The basic search terms included exercise, sleep and timing, which were combined with AND. Of the 12,203 retrieved, twenty-eight studies with 325 participants met the inclusion criteria. Results revealed that there were no significant differences in terms of impacts on sleep caused by different intensities of acute evening exercise, except that when compared to no exercise, acute evening high-intensity exercise decreased rapid eye movement sleep (mean difference [MD] = −1.95%, 95% credible interval [CI] = −3.58 to −0.35). Compared to no exercise, acute evening moderate-intensity exercise was ranked as the most potential method to improve sleep, displaying a trend to improve wake time after sleep onset (MD = −2.50 min, 95% CI = −8.17 to 1.62), sleep efficiency (MD = +0.41%, 95% CI = −0.71 to 1.66), the proportion of stage N1 (MD = −0.72%, 95% CI = −2.08 to 0.71) and N3 sleep (slow-wave sleep) (MD = +0.84%, 95% CI = −1.17 to 2.78). Acute evening low-intensity exercise displayed the greatest tendency to shorten sleep onset latency (MD = −1.02 min, 95% CI = −4.39 to 2.50) compared to no exercise. Overall, regardless of intensity, acute evening exercise completed before bedtime does not disrupt subsequent sleep in healthy young and middle-aged adults.
... D elayed-onset muscle soreness (DOMS) is a condi-could last up to 7 days regardless of the individual's physical condition. 6 However, the effects of current management of DOMS are limited due to inconsistent evidence in the literature. ...
Objective: This study aimed to investigate the effects of photobiomodulation (PBM), low-intensity stretching, and their combination on delayed-onset muscle soreness (DOMS) in the untrained population. The relationships between DOMS and muscle function and functional performance were also tested. Methods: Fifty-four participants were randomized into four groups. Eccentric exercise was used to induce DOMS. Each group received either no treatment, PBM, stretching or PBM combined with stretching at 24, 48, and 72 h postexercise. Pressure pain threshold (PPT), numerical rating scale (NRS), single-leg forward jump (SLFJ), and maximum isometric voluntary contraction (MIVC) were measured at baseline, 24, 48, 72, and 96 h after eccentric exercise. Between-group differences were tested using two-way repeated measures analysis of variance and the relationships between DOMS and MIVC, and SLFJ were examined using Pearson's correlation analysis. Results: The PPT at the vastus medialis and vastus lateral in the PBM combined with stretching group was significantly lower than that in control group at 72 h (p = 0.045) and 48 h (p = 0.037) postexercise. No significant between-group difference in PPT was found for the rest occasions. There was no significant between-group difference in NRS, MVIC, and SLFJ on any occasion (p ≥ 0.052). DOMS was not correlated with MIVC and SLFJ (p ≥ 0.09). Conclusions: PBM or low-intensity stretching did not affect DOMS and functional performance in untrained individuals. The combination of PBM and low-intensity stretching increased pain sensitivity and did not relieve soreness. The DOMS was not associated with either muscle function or functional performance.
... Delayed-onset muscle soreness (DOMS) is commonly reported by athletes or untrained individuals after highintensity eccentric exercise or by unfamiliar exercises. 33,48 Although accurate epidemiological data on DOMS are lacking due to a high number of unevaluated cases, injuries and muscle overload are common symptoms of DOMS. 45 The incidence of these injuries corresponds to 10-55% of sports injuries and are responsible for a loss of training and competition days. ...
The effectiveness of electrical stimulation (ES) in preventing or treating delayed-onset muscle soreness (DOMS) and its effects on muscle recovery is unclear. The systematic review investigated the benefits or harms of ES on DOMS and muscle recovery. Databases (PubMed, Medline, CENTRAL, EMBASE, CINAHL, PsycINFO, PEDro, LILACS, SPORTDiscus) were searched up to March, 31st 2021 for randomized controlled trials (RCTs) of athletes or untrained adults with DOMS treated with ES and compared to placebo/sham (simulation or without ES), or control (no intervention). Data were pooled in a meta-analysis. Risk of bias (Cochrane Collaboration tool) and quality of evidence (GRADE) were analyzed. Fourteen trials (n=435) were included in this review and 12 trials (n=389) were pooled in a meta-analysis. Evidence of very low to low quality indicates that ES does not prevent or treat DOMS as well as ES does not help to promote muscle recovery immediately, 24, 48, 72, 96 hours after the intervention. Only one study monitored adverse events. There are no recommendations that support the use of ES in DOMS and muscle recovery.
Perspectives
No recommendations support the use of electrical stimulation in delayed-onset muscle soreness and muscle recovery in athletes and untrained adults. This means that electrical stimulation is not fruitful for this population according those protocols used. Therefore, unlikely that further randomized controlled trials with the same approach will yield promising results.
... 2,4,5,10,11 It is commonly accepted that the main mechanisms of DOMS are related to ultrastructural damage of skeletal muscle, sarcolemmal disruption, and Z-Band streaming, caused by intense and exhausting exercise and/ or unfamiliar sporting activity. 7,12,13 An important determinant of muscle function is musculotendinous architecture, which is the arrangement of contractile and connective tissue elements within a muscle. 14 Pennation angle (PA), defined as the angle between the muscle fiber and the intramuscular tendon, is an important architectural and functional factor of a pennate muscle. ...
Background
Percussive therapy is hypothesized to speed recovery by delivering gentle, rhythmic pulses to soft tissue. However, patients often present with a differential soreness response after percussive therapy, which may lead to altered clinical outcomes.
Purpose
To compare the acute effects of percussion therapy on passive range of motion (ROM) and tissue-specific ultrasound measures (pennation angle [PA] and muscle thickness [MT]) between healthy individuals responding positively vs. negatively to percussive therapy performed on the dominant arm posterior rotator cuff.
Study Design
Cross-sectional laboratory study
Methods
Fifty-five healthy individuals were assessed on a subjective soreness scale before and after a five-minute percussive therapy session on the dominant arm posterior rotator cuff muscles. Participants with no change or a decrease in muscle soreness were assigned to the positive response group and participants who reported an increase in muscle soreness were assigned to the negative response group. Passive internal rotation (IR) and external rotation (ER) ROM and strength, and muscle architecture of the infraspinatus and teres minor were measured via ultrasound on the dominant shoulder. All dependent variables were collected before percussive therapy, and 20 minutes following percussive therapy.
Results
The positive response group had greater improvements than the negative response group in dominant arm IR ROM (2.3° positive vs. -1.3° negative, p=0.021) and IR strength (1.1 lbs vs. -1.2 lbs, p=0.011) after percussive therapy. No differences in ER strength or ROM were observed between groups. Regarding muscle architecture, the positive group had a lesser change in teres minor MT (0.00 mm vs. 0.11 mm, p=0.019) after percussive therapy. All other muscle architecture changes were not statistically different between groups.
Conclusion
Participants with a positive response to percussive therapy had increased dominant arm IR ROM and IR strength, and decreased teres minor MT, after percussive therapy compared to the negative response participants.
Level of Evidence
III
... One of the active recovery interventions can be given exercise in the form of active stretching, active stretching will stretch the myofibrils and muscle sarcomeres, it can provide the ability for muscles to contract and relax. and passive recovery interventions can be given massage therapy, the benefit of massage therapy is to reduce discomfort that occurs in the muscles (Lewis et al., 2012). ...
Background: Sport is an activity that has a positive effect on an individual. DOMS occurs when a person starts exercising after a long period of inactivity and results from an increase in the load and intensity of the exercise. DOMS is characterized by the onset of muscle soreness after exercise. Any type of activity that places an unusual load on the muscles can cause DOMS.Objective: to determine the existence of active recovery and passive recovery in reducing DOMS (delayed onset muscle soreness).Method: The study design in this research is a critical review. The data were obtained using several literature searches, namely Physiotherapy Evidence Database (PEDro), Science Direct, Google scholar, pubmed, NCBI, Jane BiosemanticResults: based on 7 articles found, 3 articles said massage with the rolling massage technique had a significant effect on reducing doms symptoms, 2 articles said it was not effective, 1 article said aerobic exercise had an effect on preventing doms and 1 article said stretching was not effective
... Theses discrepancies could be due to the large type of exercise modalities, muscle groups and study designs included into the analysis in the present review, which differ from the specific model used by Damas et al. [13]. However, it is difficult to fully explain the delayed peak of DOMS after severe EIMD due to a complex etiology of pain [26]. For instance, muscle inflammation due to white cells infiltration (i.e., macrophages) [11] and intramuscular fluid pressure [27] due to muscle swelling could be different as function of the level of MVC loss 24-48h , inducing different time-courses of DOMS. ...
Purpose
The aim of this review was to (1) characterize the time-course of markers of exercise-induced muscle damage (EIMD) based on the level of maximal voluntary contraction torque loss at 24-48h post-exercise (MVCloss24-48h), (2) identify factors (e.g., exercise and population characteristics) affecting the level of MVCloss24-48h, and (3) evaluate the appropriateness of EIMD markers as indicators of MVCloss24-48h.
Methods
Magnitude of change of each EIMD markers was normalized using the standardized mean differences method to compare the results from different studies. Time-course of EIMD markers were characterized according to three levels of MVCloss24-48h based on a clustering analysis of the 141 studies included. Association between MVCloss24-48h levels and participant´s characteristics or exercise type/modalities were assessed. Meta-regressions were performed to investigate the associations between MVCloss24-48h and EIMD markers changes at <6h, 24h, 48h, 72h and >96h after exercise.
Results
Time-course of EIMD markers recovery differs between levels of MVCloss24-48h. Training status and exercise type/modality were associated with MVCloss24-48h level (p<0.05). MVCloss24-48h was correlated to changes in myoglobin concentration (<6h), jump height (24h) and range of motion (48h) (p<0.001).
Conclusion
As the exercise could differently affect markers as function of the EIMD severity (i.e., MVCloss24-48h levels), different markers should be used as function of the timing of measurement. Mb concentration should be used during the first hours after the exercise (<6h), whereas jump height (24h) and range of motion (48h) could be used as surrogate for maximal voluntary contraction later. Moreover, training status and exercise type/modality could influence the magnitude of MVCloss24-48h.
... Soft tissue soreness is a sensation that occurs as a result of intense bouts of physical activity and can be felt immediately, hours after, or even days following activity. Muscle soreness is classified as a type I muscle strain and refers to the immediate soreness perceived by the athlete, patient, or subject immediately after participating in exercise [2]. Increases in mechanical stress trigger inflammatory responses within the muscle cell causing the production of reactive oxygen species, which in turn promote the transcription of nuclear factor kB (NF-kB) which leads to secondary muscle damage. ...
Delayed onset muscle soreness (DOMS), is a phenomenon that typically occurs within 8-48 hours, and can peak within 24-72 hours after a bout of intense resistance training[1]. To combat this pain, analgesics such as Nonsteroidal Anti-inflammatory Drugs (NSAIDs) are commonly used. Many negative risks and side effects are associated with NSAID use including but not limited to: gastrointestinal (GI) distress, ulcers, hypertension, acute renal failure, and other cardiovascular related incidences [25]. Ashwagandha is an Indian herbal supplement believed to have anti-inflammatory and analgesic properties. The purpose of this study was to assess the effects of Ashwagandha on DOMS following a bout of intense exercise. Fifteen (n=15) college aged individuals (18-23 years of age), volunteered to participate in this study and were randomly placed in either an experimental condition (n=8), (750mg dose of Ashwagandha), or a placebo condition (n=7). The subjects completed an intense lower-body exercise protocol consisting of 5 sets of 20 weighted lunges at 40% body weight, along with 3 sets to failure of 75% body weight on a leg press machine. Testing measurements consisted of a Visual Analog Scale (VAS), pain pressure threshold, thigh circumference, peak power output, ground contact time, peak velocity, and vertical jump. Measurements were taken at pre-test, post resistance training bout, day 3, and day 6. VAS measurements were recorded days 1-5. Statistical analysis showed a statistically significant difference in peak power (W) output on Day 3 in the experimental group, (M= 1659.873, SD 614.104) compared to the control group (M=1401.214, SD= 306.669), t(10.558)=1.051, p<0.016. No other measurements showed statistically significant difference among the groups. This demonstrates Ashwagandha has the ability to improve, or maintain peak power output measures on the third day following an intense bout of lower body resistance training exercises.
Introduction: Delayed Onset Muscle Soreness (DOMS) is
a common consequence of ultrastructural muscle damage.
Following unusual eccentric exercises, individuals who are
not professionally trained or are amateur athletes experience
muscle tenderness that can range from mild discomfort to
severe debilitating pain.
Aim: To identify the factors that contribute to the development
of DOMS in untrained athletes and to raise awareness about
these factors.
Materials and Methods: A cross-sectional observational study
was conducted in the Department of Physiotherapy, GEMS
College of Physiotherapy, Srikakulam, Andhra Pradesh, India
on 50 untrained athletes aged 18-25 years, over a period of
eight months from January to September 2022, with complete
enrollment of untrained athletes. The history of pain, stiffness,
decreased range of motion and DOMS was surveyed through a
self-reported questionnaire, followed by quantitative statistical
analysis using mean, standard deviation and percentages of the
data.
Results: The mean age of the participants was 21.04±2.7401
years. The current research examined various predisposing
factors that influenced the occurrence of DOMS. Specifically,
35 (70%) athletes reported engaging in eccentric exercises; 24
(48%) athletes reported exposure to hot weather and outdoor
environments; 32 (64%) athletes reported neglecting warm-up
sessions; and 43 (86%) athletes reported skipping cool-down
exercises.
Conclusion: The study concluded that the group of muscles
comprising the shoulders and biceps is particularly susceptible
to experiencing pain, loss of strength, muscle tenderness
and reduced range of motion as a result of DOMS. DOMS is
commonly induced by engaging in high-intensity workouts,
such as lifting heavy weights with eccentric contractions,
without proper warm-up and cool-down routines, especially in
hot outdoor environments.
We aimed to assess high-density surface electromyography (HDsEMG)-torque relationships in the presence of delayed onset trunk muscle soreness (DOMS) and the effect of these relationships on torque steadiness (TS) and lumbar movement during concentric/eccentric submaximal trunk extension contractions. Twenty healthy individuals attended three laboratory sessions (24 h apart). HDsEMG signals were recorded unilaterally from the thoracolumbar erector spinae with two 64-electrode grids. HDsEMG-torque signal relationships were explored via coherence (0–5 Hz) and cross-correlation analyses. Principal component analysis was used for HDsEMG-data dimensionality reduction and improvement of HDsEMG-torque-based estimations. DOMS did not reduce either concentric or eccentric trunk extensor muscle strength. However, in the presence of DOMS, improved TS, alongside an altered HDsEMG-torque relationship and kinematic changes were observed, in a contraction-dependent manner. For eccentric trunk extension, improved TS was observed, with greater lumbar flexion movement and a reduction in δ-band HDsEMG-torque coherence and cross-correlation. For concentric trunk extensions, TS improvements were observed alongside reduced thoracolumbar sagittal movement. DOMS does not seem to impair the ability to control trunk muscle force, however, perceived soreness induced changes in lumbar movement and muscle recruitment strategies, which could alter motor performance if the exposure to pain is maintained in the long term.
Introduction: Benefits of protein consumption are established, yet athletes often consume insufficient protein. The effect of protein supplementation timing on self- reported wellness measures (SRWM) is unknown. The purpose was to examine the effect of protein supplementation timing on overall protein intake and SRWM. Methods: Collegiate athletes (men: n=13; body mass: 76.1 ± 6.6 kg; body fat %: 14.8 ± 2.3%) (women: n=16; body mass: 72.5 ± 10.8 kg; body fat %: 24.9 ± 4.6%), defined as protein-insufficient (daily intake <1.5 g/kg body weight) participated. Protein supplementation occurred over two 2-week periods (morning, evening) separated by a 2-week washout. Daily SRWM (fatigue, soreness, sleep, stress, mood, energy, recovery, satiety) were collected. ANOVA assessed differences in total protein intake and SRWM measures across conditions. Spearman correlations assessed relationships between protein intake and SRWM.Results: No sex difference existed in protein intake based on supplementation timing. Compared to baseline, morning and evening supplementation led to an increase (p<0.05) in absolute and relative protein intake for men and women. Satiety was increased during morning and evening conditions compared to washout for men (p=0.004) and women (p=0.012), but other SRWM did not differ. Correlations existed for relative protein intake and satiety (r=0.499, p<0.001) and stress (r=-0.321, p=0.019).Conclusions: Protein supplementation enabled participants to achieve the recommended protein intake and provided a greater feeling of satiety. Satiety did not differ between morning and evening, providing flexibility as to when to ingest a daily supplement.
Objectives: This study aimed to analyze how spatiotemporal gait parameters, active knee extension range of motion, muscle activity, and self-perceived function change over a seven-day period in healthy individuals after exercise-induced muscle damage (EIMD) in the hamstrings.
Design: Longitudinal cohort study.
Methods: Twenty-four healthy males participated in four sessions before and after EIMD (pre-EIMD, 48 h, 96 h, and 168 h post-EIMD). A single-leg deadlift exercise was performed to provoke EIMD in the hamstrings of the dominant leg. Lower limb function perception, spatiotemporal gait parameters, active knee extension range of
motion, and electromyographic (EMG) activity of the semitendinosus and biceps femoris muscles during gait and maximal isometric contraction were assessed bilaterally.
Results: At 48 h, the EIMD-side showed reduced step length, active knee extension range of motion, maximal strength and EMG activity compared to baseline (P < 0.042), while increased relative EMG activity in the biceps femoris during gait (P = 0.001). At 96 h, step length and EMG activity on the EIMD-side reached similar values to
those at baseline, whereas lower limb function perception and active knee extension range of motion returned to baseline state at 168 h post-EIMD. No changes over time were observed on the control-side.
Conclusions: Recovery from EIMD requires a multimodal assessment since the different parameters affected by EIMD recover at different paces. Active range of motion appears to be the last variable to fully recover. Self-perceived function should not be considered in isolation as it does not represent complete functional recovery.
The aim of this study is to investigate the effects of wearable local vibration therapy (VT) on muscle soreness, joint position sense, and dynamic balance in recovery after squat exercise. Twenty males (age: 22.25±1.97 years) participated in the study. Muscle soreness, joint position sense, and dynamic balance were evaluated before exercise, 24 and 48 hours after exercise. All participants performed six sets of 10 repetitions of squat exercises. VT was applied to one thigh of the participants randomly for 10 minutes after exercise, and the other thigh was determined as the control. The muscle soreness increased significantly for VT (p.05). No significant difference was found between VT and control (p>0.05). No significant difference was found after exercise at knee joint position sense for both conditions (p>.05). No significant difference was observed between VT and control (p>.05). There was a significant difference between before exercise and 48 hours after exercise at anterior direction of the modified Star Excursion Balance Test for VT (p=.033). A significant difference was found between before exercise and 24 hours after exercise at posteromedial (p=.012) direction for VT. There was only significant difference at posteromedial (p=.028) direction at 24 hours after exercise between VT and control. The wearable local VT after squat exercise did not affect muscle soreness and knee joint position sense. However, local VT contributed to the improvement of dynamic balance.
Lower limb injuries above and below the knee are common in the athletic population. An accurate diagnosis through a rapid and systematic approach in the initial assessment of an injured athlete on the sideline is crucial. Sideline management starts with the injury mechanism. In order to provide a proper diagnostic sideline setup, it is important that the medical staff is actively present during match/competition/training. As the time is limited on the sideline, it is important to focus, to understand the specificities of the sport, and to ask the relevant questions. The direct decision making—whether the athlete can continue to perform or not—can have major implications for the athlete and the team and is subject to different variables that will be addressed in this chapter. In terms of lower limb injuries, contusions and muscle strains are the most common conditions. However, acute fractures and stress fractures are more severe with a longer time loss. Differential diagnoses are important to not miss uncommon injuries.
Numerous studies have evaluated the efficacy of interventions to improve locomotion after acute-onset brain injury, although most focus on patients with stroke, with less attention toward traumatic brain injury (TBI). For example, a number of studies in patients post-stroke have evaluated the effects of high-intensity training (HIT) attempting to maximize stepping practice, while no studies have attempted this intervention in patients with TBI. The purpose of this blinded-assessor randomized trial was to evaluate the effects of HIT focused on stepping practice versus conventional training on walking and secondary outcomes in individuals with TBI. Using a crossover design, ambulatory participants with TBI >6-months duration performed HIT focused on stepping in variable contexts (overground, treadmill, stairs) or conventional training for up to 15 sessions over five weeks, with interventions alternated >4 weeks later. HIT focused on maximizing stepping practice while trying to achieve higher cardiovascular intensities (>70% heart rate reserve), while conventional training focused on impairment-based and functional exercises with no restrictions on intensities achieved. Greater increases in 6-min walk test and peak treadmill speed during graded exercise testing were observed after HIT versus conventional training, with moderate associations between differences in stepping practice and outcomes. Greater gains were also observed in estimates of aerobic capacity and efficiency after HIT, with additional improvements in selected cognitive assessments. The present study suggests that the amount and intensity of stepping practice may be important determinants of improved locomotor outcomes in patients with chronic TBI, with possible secondary benefits on aerobic capacity/efficiency and cognition. Clinical Trial Registration-URL: https://clinicaltrials.gov/; Unique Identifier: NCT04503473.
Background
The effectiveness of acupuncture and tuina in treating knee osteoarthritis (KOA) is still controversial, which limits their clinical application in practice. This study aims to evaluate the short-term and long-term effectiveness of acupuncture and tuina on KOA.
Methods/design
This parallel-group, multicenter randomized clinical trial (RCT) will be conducted at the outpatient clinic of five traditional Chinese medicine hospitals in China. Three hundred and thirty participants with KOA will be randomly assigned to acupuncture, tuina, or home-based exercise group with a ratio of 1:1:1. The primary outcome is the proportion of participants achieving a minimal clinically important improvement defined as a ≥ 12% reduction on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain dimension on short term (week 8) and long term (week 26) compared with baseline. Secondary outcomes are knee joint conditions (pain, function, and stiffness), self-efficacy of arthritis, quality of life, and psychological conditions, which will be evaluated by the WOMAC score and the Patient Global Assessment (PGA), and in addition, the respondents index of OMERACT-OARSI, Short Form 12 Health Survey (SF-12), arthritis self-efficacy scale, and European five-dimensional health scale (EQ-5D). Adverse events will be collected by self-reported questionnaires predefined.
Clinical trial registration
https://www.chictr.org.cn
Cold application is one of the simplest and oldest treatment methods generally used in sports injuries,
acute musculoskeletal pain, inflammatory diseases, overuse injuries. Cryotherapy is a term used to
describe therapeutic processes that usually involve local or systemic cold applications. Cold application
has many different physiological effects on the body. Decreasing the temperature of the damaged tissue
can induce vasoconstriction, reducing local metabolism, inflammation, pain, and muscle spasm. The use
of cold application for various purposes was included in the Edwin Smith Papyrus in the 16th century
BC, and treatment protocols including this application developed over time as ICE, RICE, PRICE,
POLICE and PEACE&LOVE. Cryotherapy has various application modalities such as cold water
immersion, whole body cryotherapy, partial body cryotherapy, cold packs, cold compress machines, ice
massage, neurocryostimulation. Many studies have been carried out on this subject to date, and research
is still ongoing. However, there is no consensus on which of the cryotherapy modalities is more
effective, the ideal treatment duration, and the advantages and disadvantages of its use in injuries. The
aim of this review is to reveal the historical development of cold application, application modalities and
treatment agents, physiological effects and its use in soft tissue injuries in the light of current literature.
Keywords: cold application, injury, cryotherapy, cold application in injuries, mechanism of action.
Soğuk uygulama genellikle spor yaralanmaları, akut kas-iskelet sistemi ağrıları, inflamatuar hastalıklar,
aşırı kullanımdan kaynaklı yaralanmalarda kullanılan basit ve en eski tedavi yöntemlerinden biridir.
Kriyoterapi, genellikle lokal ya da sistemik soğuk uygulamaları içeren terapötik süreçleri tanımlamak
için kullanılan bir terimdir. Soğuk uygulama vücutta birçok farklı fizyolojik etkiye sahiptir. Hasarlı
dokunun sıcaklığının düşürülmesi vazokonstriksiyona neden olarak lokal metabolizmayı, inflamasyonu,
ağrıyı ve kas spazmını azaltabilir. Soğuk uygulamanın çeşitli amaçlarla kullanımı MÖ 16. yüzyılda
Edwin Smith Papirüsünde yer almış, bu uygulamayı içeren tedavi protokolleri zaman içerisinde ICE,
RICE, PRICE, POLICE ve PEACE&LOVE olarak gelişmiştir. Kriyoterapinin soğuk suya daldırma, tüm
vücut kriyoterapisi, kısmi vücut kriyoterapisi, soğuk paketler, soğuk kompres cihazları, buz masajı,
nörokriyostimülasyon gibi çeşitli uygulama modaliteleri bulunmaktadır. Günümüze kadar bu konu
hakkında birçok çalışma yapılmış ve araştırmalar halen devam etmektedir. Bununla birlikte kriyoterapi
modalitelerinin hangisinin daha etkili olduğu, ideal tedavi süresi ve yaralanmalarda kullanımının avantaj
ve dezavantajları konusunda fikir birliği yoktur. Bu derlemenin amacı soğuk uygulamanın tarihsel
gelişimi, uygulama modaliteleri ve tedavi ajanları, fizyolojik etkileri ve yumuşak doku yaralanmalarında
kullanımını güncel literatür eşliğinde ortaya koymaktır.
Anahtar Kelimeler: soğuk uygulama, yaralanma, kriyoterapi, yaralanmalarda soğuk uygulama, etki
mekanizması.
Eccentric muscle contractions can cause structural damage to muscle cells resulting in temporarily decreased muscle force production and soreness. Prior work indicates pasture-raised dairy products from grass-fed cows have greater anti-inflammatory and antioxidant properties compared to grain-fed counterparts. However, limited research has evaluated the utility of whey protein from pasture-raised, grass-fed cows to enhance recovery compared to whey protein from non-grass-fed cows. Therefore, using a randomized, placebo-controlled design, we compared the effect of whey protein from pasture-raised, grass-fed cows (PRWP) to conventional whey protein (CWP) supplementation on indirect markers of muscle damage in response to eccentric exercise-induced muscle damage (EIMD) in resistance-trained individuals. Thirty-nine subjects (PRWP, n = 14; CWP, n = 12) completed an eccentric squat protocol to induce EIMD with measurements performed at 24, 48, and 72 h of recovery. Dependent variables included: delayed onset muscle soreness (DOMS), urinary titin, maximal isometric voluntary contraction (MIVC), potentiated quadriceps twitch force, countermovement jump (CMJ), and barbell back squat velocity (BBSV). Between-condition comparisons did not reveal any significant differences (p ≤ 0.05) in markers of EIMD via DOMS, urinary titin, MIVC, potentiated quadriceps twitch force, CMJ, or BBSV. In conclusion, neither PRWP nor CWP attenuate indirect markers of muscle damage and soreness following eccentric exercise in resistance-trained individuals.
Traumatic muscle injury represents a collection of skeletal muscle pathologies caused by trauma to the muscle tissue and is defined as damage to the muscle tissue that can result in a functional deficit. Traumatic muscle injury can affect people across the lifespan and can result from high stresses and strains to skeletal muscle tissue, oftendue to muscle activation while the muscle is lengthening, resultingin indirect and non-contact muscle injuries (strains or ruptures), orfrom external impact, resulting in direct muscle injuries (contusionor laceration). At a microscopic level, muscle fibres can repair focal damage but must be completely regenerated after full myofibrenecrosis. The diagnosis of muscle injury is based on patient history andphysical examination. Imaging may be indicated to eliminate differentialdiagnoses. The management of muscle injury has changed within thepast 5 years from initial rest, immobilization and (over)protection toearly activation and progressive loading using an active approach.One challenge of muscle injury management is that numerous medicaltreatment options, such as medications and injections, are often usedor proposed to try to accelerate muscle recovery despite very limitedefficacy evidence. Another challenge is the prevention of muscle injuryowing to the multifactorial and complex nature of this injury.
Pendahuluan: Delayed Onset Muscle Soreness (DOMS) adalah nyeri yang dirasakan seseorang dalam waktu 24-72 jam setelah melakukan aktivitas olahraga. DOMS menimbulkan kekakuan, bengkak, penurunan kekuatan dan nyeri pada otot. Salah satu pemicu DOMS adalah olahraga eksentrik. Beberapa penelitian mengatakan bahwa pendinginan ikut berpengaruh dalam mengurangi terjadinya cedera otot sesudah berolah raga, tetapi banyak juga penelitian yang mengatakan bahwa pendinginan tidak berpengaruh dalam mengurangi risiko cedera otot setelah olah raga. Tujuan penelitian ini adalah untuk mengetahui apakah pendinginan meringankan nyeri yang timbul setelah berjalan jongkok pada mahasiswa perempuan angkatan 2012 FKIK Unika Atma Jaya.Metode: Penelitian ini bersifat intervensi, jumlah responden 69 orang dibagi dalam 23 orang kelompok kontrol, 23 orang kelompok perlakuan 1, dan 23 orang kelompok perlakuan 2. Setiap responden melakukan pemanasan selama 5 menit, jalan jongkok 8x18 langkah. Kelompok perlakuan 1 melakukan pendinginan selama 5 menit, kelompok perlakuan 2 selama 10 menit, sedangkan kelompok kontrol tidak melakukan pendinginan. Hasil: Uji Chi-Square menunjukkan perbedaan signifikan antara responden yang melakukan pendinginan dan tidak melakukan pendinginan (p<0.05). Simpulan: Pendinginan dapat meringankan gejala delayed onset muscle soreness (DOMS) pada mahasiswi angkatan 2012 FKIK Unika Atma Jaya.Kata Kunci: pendinginan, DOMS
Background:
Ice hockey players are at high risk for hip and groin injury. Several risk factors have been identified or proposed, including lower hip rotation range of motion (ROM), lower hip adductor strength, lower ratio of hip adductor to abductor strength, and lower pelvic tilt angle. It is not known how these risk factors change acutely with ice hockey participation.
Hypothesis:
Acute exposure to ice hockey will result in a reduction in ROM, strength, and pelvic tilt angle in competitive male players.
Study design:
Controlled cohort study.
Level of evidence:
Level 3.
Methods:
Risk factors for hip and groin injury, including isometric hip adductor strength at 0° of flexion, the ratio of hip adductor to abductor strength, total hip rotation passive ROM in supine, and the resting pelvic tilt angle, were assessed immediately before, immediately after, and 24 hours after an ice hockey exposure in 42 competitive male ice hockey players. Rating of perceived exertion (RPE) was collected to identify the intensity of the exposure.
Results:
There was a significant decrease in total hip rotation ROM (-7.32°, P < 0.01 (-3.91, -10.70)) and hip adductor strength (-4.41 kg, P < 0.01 (-2.81, -6.00) immediately after the exposure, and a significant decrease in total hip rotation ROM (-18.54°, P < 0.01 (-14.35, -22.73)), hip adductor strength (-6.56 kg, P < 0.01 (-4.58, -8.61)), and the ratio of hip adductor to abductor strength (-0.12, P < 0.01 (-0.21, -0.45)) 24 hours after. There was no significant change in pelvic tilt found in this study immediately after or 24 hours after. There was a moderate relationship between changes in hip adductor strength and changes in the ratio of hip adductor to abductor strength (r = 0.433, P < 0.01). RPE was not significantly correlated to any of the changes observed.
Conclusion:
Risk factors for hip and groin injury in ice hockey players are modifiable after a single ice hockey exposure.
Clinical relevance:
The identified fluctuation of injury risk factors for hip and groin injury in ice hockey players has implications for injury risk profiling, rehabilitation, and return-to-competition decision-making.
Context:
Handheld percussive massage devices (i.e., massage guns) are relatively new and under-researched recovery. These tools are intended to increase range of motion and reduce muscle soreness through delivering targeted vibration to soft tissues. There is a scarcity of empirical knowledge about the potential influence of these devices on perceptual recovery and recovery of performance characteristics after exercise.
Objective:
The current study aimed to investigate the effect of a commercially available massage gun on physical and perceptual recovery after a strenuous bout of lower-body exercise.
Design:
Repeated-measure, single-group design that implemented an experimental leg (massage gun recovery - GUN) and a control leg (passive recovery - CON).
Setting:
Testing occurred in a physiology laboratory.
Participants:
65 active young adults (34 female, 31 male) participated in this study.
Intervention:
Application of a massage gun for 5 minutes on the calf muscles after strenuous exercise.
Main outcome measures:
Ankle range of motion, calf circumference, isometric strength, calf endurance and perceived muscle soreness measures were collected at baseline, and at various points following lower-body exercise.
Results:
No significant group × time interactions were recorded for any of the performance or perceptual measures (p >0.05). Effect sizes were mostly unclear, with the exception of a small increase in perceived muscle soreness in GUN compared to CON immediately post-recovery (d = -0.35) and four hours post-recovery (d = -0.48).
Conclusions:
Massage guns appear to have little effect on physical measures when applied for five minutes immediately following strenuous calf exercise. Given the small increase in muscle soreness up to four hours following their use, caution is recommended when using massage guns immediately following strenuous lower-body exercise.
Saha zeminlerinin kas hasarı üzerindeki etkisi konusunda
yapılan çalışmalardan çıkan sonuçlar tartışmaya açıktır. Bazı çalışmalarda doğal çim ve suni çim zeminlerin kas hasarında farklılık yaratmadığı, bazılarında ise farklılıkların olduğu açıklanmıştır.
Genel kanaat, suni zeminlerin kas hasarı üzerindeki olumsuz etkilerinin daha fazla olduğu yönünde olsa da bu konuda yapılan çalışma sonuçlarına bakıldığında; zeminden ziyade esas etkenin "antrenman ve maç yoğunlukları" olduğu görüşü ağır basmaktadır.
L’objectif principal de ce travail de thèse était d’évaluer l’intérêt de « nouveaux » marqueurs de dommages musculaires, à savoir les microARNs circulants et la raideur musculaire mesurée par élastographie. Avant d’évaluer l’intérêt de ces « nouveaux » marqueurs, ce travail de thèse s’est attelé à caractériser de manière quantitative la réponse des marqueurs de dommages musculaires les plus couramment utilisés par une revue systématique avec méta-analyses portant sur une quantité importante de données issues de la littérature. L’intérêt des « nouveaux » marqueurs a été évalué en réponse à deux modèles d’exercices : un modèle d’ultra-endurance (24 h de course à pied ; pour les microARNs circulants) et un modèle de marche en descente avec port de charge. L’exercice de marche en descente a été réalisé deux fois à deux semaines d’intervalle afin d’évaluer les réponses adaptatives conférées par le « repeated bout effect ». Si aucun des marqueurs couramment utilisés ne semble être en mesure de prédire parfaitement la réduction prolongée de la fonction neuromusculaire, certaines recommandations peuvent être données sur le(s) marqueur(s) à privilégier en fonction du moment où le diagnostic est effectué. De plus, les résultats de ce travail de thèse montrent que les miARNs circulants et la raideur musculaire mesurée par élastographie peuvent avoir un intérêt dans le diagnostic des dommages musculaires, d’autant plus lorsqu’ils sont combinés avec les marqueurs classiques. Par ailleurs, l’évaluation de la raideur musculaire mesurée par élastographie a permis de mettre en évidence des adaptations mécaniques qui semblent survenir en réponse à un exercice excentrique : les muscles deviendraient plus raides afin de se protéger contre des dommages musculaires ultérieurs. Ces travaux de thèse ont donc permis de mettre en évidence (1) l’intérêt de « nouveaux » marqueurs de dommages musculaires et (2) que l’augmentation de la raideur musculaire est impliquée dans les adaptations à l’exercice excentrique.
In this article, we proposed a novel dual to ratio cum product type exponential estimator in stratified random sampling. The bias and mean square error up to the first degree of approximation of the proposed estimator have been obtained. The proposed estimator has been compared with the unbiased estimator in stratified random sampling, combined ratio and product estimators, dual to combined ratio, and product estimators. Our results showed a great improvement in terms of relative efficiency. Also, the results are supported by empirical studies. MSC: 62D05 RESUMEN En este artículo proponemos un estimador novedoso dual para el estimador acumulativo del tipo producto exponencial en el muestreo estratificado. El sesgo y el error cuadrático medio son obtenidos desarrollando en series hasta el primer grado de aproximación del estimador propuesto. Ese es comparado con los estimadores: insesgado en el muestreo estratificado, razón combinada, producto, dual de la razón combinada y del producto. Nuestros resultados mostraron una gran incremento en términos de la relativa eficiencia. También los resultados son soportado empíricamente. PALABRA CLAVE: Estimador de Razón y Producto, Media Poblacional, Sesgo, Error Cuadrático Medio, , Eficiencia.
Introduction:
Acute musculoskeletal injuries have diverse symptomatology and a multidimensional recovery process, including changes in swelling, redness, hyperalgesia, and expanded pain distribution. In a small proportion of cases, the tissue heals, although these symptoms persist, reflecting altered peripheral and central pain mechanisms. However, the otherwise healthy multidimensional recovery process following damage and pain is less than clear. The objective was to assess mechanical muscle hyperalgesia, skin temperature, and pain intensity and distribution during the recovery process in response to eccentric exercise in the hamstring muscles.
Methods:
Twenty-four healthy males participated in four sessions (Day-0, Day-2, Day-4, and Day-7). Exercise-induced muscle soreness was induced on Day-0 by five sets of 20 repetitions of an eccentric exercise involving the hamstrings on the dominant leg. Each session included assessments of thermography, pressure pain thresholds (PPTs), pain intensity, and area of exercise-induced pain.
Results:
Decreased PPTs (P < 0.005), higher pain intensity (P < 0.001), and a larger area of pain (P < 0.001) were displayed on Day-2 and Day-4 than Day-0. Skin temperature decreased on Day-2 than Day-0 (P < 0.01) and returned to baseline assessments by Day-4, despite lower temperature than the contralateral tight (P < 0.01). Further, there was a positive correlation between pain intensity and area on Day-2 and Day-4 (P < 0.005), but no for changes in skin temperature.
Conclusion:
Thermographic changes and pain-related variables altered following eccentric exercise demonstrate different recovery times. These results provide insights into potential mechanisms and measures that can be used to assess recovery from exercise-induced damage.
Delayed post-exercise muscle pain is a type of pain that is felt within the first 24 hours after exercise, peaks between 1 and 3 days, compared to acute muscle pain, and its effect decreases completely after 5-7 days. There is increasing interest and research into delayed muscle pain. Although there are different formation mecha- nisms on delayed muscle pain, the formation mechanisms have not been fully exp- lained. Nutritional interventions are one of the preventive and/or therapeutic ways to reduce delayed muscle soreness. Studies have reported that nutritional interven- tions can reduce delayed muscle soreness. Many studies have reported the effect of caffeine, omega-3 fatty acids, taurine, polyphenols, and curcumin on delayed muscle soreness. Consistent data have not been reported from minor interventions with supplements such as antioxidants, L-carnitine, BCAA, allicin. Delayed musc- le soreness is an area that needs more study in athletes. There is a need for more studies examining these factors by considering more factors such as the severity of the damage, individual response, the dose-response relationship used, the duration of intake and the markers they are affected by. The aim of this review is to address nutritional interventions that are thought to be effective in the treatment and pre- vention of delayed muscle pain and to discuss the relationship between delayed muscle pain and nutrition.
Keywords: Nutrition, doms, delayed muscle soreness
The purposes of this study were, first, to clarify the long-term pattern of T2 relaxation times and muscle volume changes in human skeletal muscle after intense eccentric exercise and, second, to determine whether the T2 response exhibits an adaptation to repeated bouts. Six young adult men performed two bouts of eccentric biceps curls (5 sets of 10 at 110% of the 1-repetition concentric maximum) separated by 8 wk. Blood samples, soreness ratings, and T2-weighted axial fast spin-echo magnetic resonance images of the upper arm were obtained immediately before and after each bout; at 1, 2, 4, 7, 14, 21, and 56 days after bout 1; and at 2, 4, 7 and 14 days after bout 2. Resting muscle T2 [27.6 ± 0.2 (SE) ms] increased immediately postexercise by 8 ± 1 ms after both bouts. T2 peaked 7 days after bout 1 at 47 ± 4 ms and remained elevated by 2.5 ms at 56 days. T2 peaked lower (37 ± 4 ms) and earlier (2–4 days) after bout 2, suggesting an adaptation of the T2 response. Peak serum creatine kinase values, pain ratings, and flexor muscle swelling were also significantly lower after the second bout ( P < 0.05). Total volume of the imaged arm region increased transiently after bout 1 but returned to preexercise values within 2 wk. The exercised flexor compartment swelled by over 40%, but after 2 wk it reverted to a volume 10% smaller than that before exercise and maintained this volume loss through 8 wk, consistent with partial or total destruction of a small subpopulation of muscle fibers.
Muscle soreness, a familiar phenomenon to most athletes, has been differentiated into 'acute' and 'delayed onset'. The etiology of acute muscle soreness has been attributed to ischemia and the accumulation of metabolic by-products. However, the etiology of delayed onset muscle soreness (DOMS) is not so clear. Six theories have been proposed: lactic acid, muscle spasm, torn tissue, connective tissue, enzyme efflux, and tissue fluid theories. The treatment of DOMS has also been investigated. Studies in which anti-inflammatory medications have been administered have yielded varying results based on the dosage and the time of administration. Submaximal concentric exercise may alleviate soreness but does not restore muscle function. Neither cryotherapy nor stretching abates the symptoms of DOMS. Transcutaneous electrical stimulation]Ins been shown to decrease soreness and increase range of motion, but the effect on the recovery of muscle function is unknown. Therefore, the treatment of DOMS remains an enigma.
Delayed onset muscle soreness (DOMS) is a familiar experience for the elite or novice athlete. Symptoms can range from muscle tenderness to severe debilitating pain. The mechanisms, treatment strategies, and impact on athletic performance remain uncertain, despite the high incidence of DOMS. DOMS is most prevalent at the beginning of the sporting season when athletes are returning to training following a period of reduced activity. DOMS is also common when athletes are first introduced to certain types of activities regardless of the time of year. Eccentric activities induce micro-injury at a greater frequency and severity than other types of muscle actions. The intensity and duration of exercise are also important factors in DOMS onset. Up to six hypothesised theories have been proposed for the mechanism of DOMS, namely: lactic acid, muscle spasm, connective tissue damage, muscle damage, inflammation and the enzyme efflux theories. However, an integration of two or more theories is likely to explain muscle soreness. DOMS can affect athletic performance by causing a reduction in joint range of motion, shock attenuation and peak torque. Alterations in muscle sequencing and recruitment patterns may also occur, causing unaccustomed stress to be placed on muscle ligaments and tendons. These compensatory mechanisms may increase the risk of further injury if a premature return to sport is attempted.
A number of treatment strategies have been introduced to help alleviate the severity of DOMS and to restore the maximal function of the muscles as rapidly as possible. Nonsteroidal anti-inflammatory drugs have demonstrated dosage-dependent effects that may also be influenced by the time of administration. Similarly, massage has shown varying results that may be attributed to the time of massage application and the type of massage technique used. Cryotherapy, stretching, homeopathy, ultrasound and electrical current modalities have demonstrated no effect on the alleviation of muscle soreness or other DOMS symptoms. Exercise is the most effective means of alleviating pain during DOMS, however the analgesic effect is also temporary. Athletes who must train on a daily basis should be encouraged to reduce the intensity and duration of exercise for 1–2 days following intense DOMS-inducing exercise. Alternatively, exercises targeting less affected body parts should be encouraged in order to allow the most affected muscle groups to recover. Eccentric exercises or novel activities should be introduced progressively over a period of 1 or 2 weeks at the beginning of, or during, the sporting season in order to reduce the level of physical impairment and/or training disruption. There are still many unanswered questions relating to DOMS, and many potential areas for future research.
In this study, we investigated the effects of two hydrotherapy interventions on match running performance and perceptual measures of fatigue and recovery during a 4-day soccer tournament. Twenty male junior soccer players were assigned to one of two treatment groups and undertook either cold-water immersion (5 × 1 min at 10 °C) or thermoneutral water immersion (5 × 1 min at 34 °C) after each match. High-intensity running distance (>15 km · h⁻¹) and total distance covered, time spent in low (<80% maximum heart rate), moderate (80-90% maximum heart rate), and high (>90% maximum heart rate) heart rate zones, and rating of perceived exertion (RPE) were recorded for each match. Perceptions of general fatigue and leg soreness were recorded approximately 22 h after each match. There were decreases in both groups across the 4-day tournament for high-intensity running distance (P = 0.006, Cohen's d = 0.63), total distance run (P < 0.001, d = 0.90), time in high heart rate zone (P = 0.003, d = 0.90), and match RPE (P = 0.012, d = 0.52). Cold-water immersion was more effective than thermoneutral immersion for reducing the perception of leg soreness (P = 0.004, d = -0.92) and general fatigue (P = 0.007, d = -0.91), ameliorating the decrement in total distance run (P = 0.001, d = 0.55), and maintaining time in the moderate heart rate zone (P = 0.01, d = 1.06). In conclusion, cold-water immersion mediates the perceptions of fatigue and recovery and enhances the restoration of some match-related performance measures during a 4-day tournament.
Exercise-induced muscle damage (EIMD) leads to decrements in muscle performance and increases in intramuscular enzymes measured in the plasma, and to delayed onset of muscle soreness (DOMS), partly due to the activation of degradative pathways. It has been shown that milk-based carbohydrate-protein (CHO-P) can limit changes in markers of EIMD, possibly by attenuating protein degradation and (or) increasing protein synthesis. However, the timing of supplementation has received limited attention, and this may alter the response. This study examined the effects of acute milk-based CHO-P supplementation timing on the attenuation of EIMD. Four independent matched groups of 8 healthy males consumed milk-based CHO-P before (PRE), immediately after (POST), or 24h after (TWENTY-FOUR) muscle-damaging exercise. Active DOMS, isokinetic muscle performance, reactive strength index (RSI), and creatine kinase (CK) were assessed immediately before and 24, 48, and 72h after EIMD. POST and TWENTY-FOUR demonstrated a benefit in limiting changes in active DOMS, peak torque, and RSI over 48h, compared with PRE. PRE showed a possible benefit in reducing increases in CK over 48h and limiting changes in other variables over 72h. Consuming milk-based CHO-P after muscle-damaging exercise is more beneficial in attenuating decreases in muscle performance and increases in active DOMS at 48 h than ingestion prior to exercise.
Temporary muscle damage precipitated by downhill walking affects muscle function and potentially exposes muscle to further musculoskeletal injury.
We hypothesized that the use of trekking poles would help maintain muscle function and reduce indices of muscle damage after a day's mountain trekking.
Thirty-seven physically active males (n = 26) and females (n = 11) volunteered to participate and were divided into either a trekking pole (TP) or no pole (NP) group. Participants carried a day sack (5.6 ± 1.5 kg) and made the ascent and descent of the highest peak in England and Wales (Mount Snowdon). HR and RPE were recorded during the ascent and descent. Indices of muscle damage, namely, maximal voluntary contraction, muscle soreness, creatine kinase (CK), and vertical jump performance, were measured before, immediately after (except CK), and 24, 48, and 72 h after trek.
HR was not different between groups, although RPE was significantly lower in TP during the ascent. The TP group showed attenuation of reductions in maximal voluntary contraction immediately after and 24 and 48 h after the trek; muscle soreness was significantly lower at 24 and 48 h after the trek, and CK was also lower at 24 h after the trek in the TP group. No differences in vertical jump were found.
Trekking poles reduce RPE on mountain ascents, reduce indices of muscle damage, assist in maintaining muscle function in the days after a mountain trek, and reduce the potential for subsequent injury.
The aim of this paper was to assess the effects of branched-chain amino acid (BCAA) supplementation on muscle soreness, muscle damage and inflammation during an intensive training program.
Twelve long-distance runners (20 + or - 1 year-old) participated in a double-blinded crossover designed study conducted during two intensive training periods (three-day). The subjects were provided either a drink containing BCAA (0.8% BCAA in a 3.5% carbohydrate solution; 2,500 mL/day) or an isocaloric placebo drink during each training period. All subjects completed the same training program (total running distance: males: 86 km, females: 64 km), and ate the same meals during the training period. Whole body muscle soreness and fatigue sensation were measured in the morning before and during the training period by Visual Analogue Scale method. Plasma creatine kinase (CK), lactate dehydrogenase (LDH), and granulocyte elastase (GEL) levels were measured as indicators of muscle damage and inflammation before and after the training period.
Muscle soreness and fatigue sensation during the training period in the BCAA trial were lower than those in the placebo trial (-32% and -24%, respectively; P<0.05). The plasma CK, LDH, and GEL levels after the training program in the BCAA trial were lower than those in the placebo trial (-21%, -6%, and -15%, respectively; P<0.05).
These results demonstrate that BCAA supplementation during an intensive training program effectively reduces the muscle soreness and fatigue sensation, and that the perceived changes could be attributed to the attenuation of muscle damage and inflammation.
To investigate the time course of leukocyte accumulation in eccentric exercised human muscles and its relation to recovery of muscle function and soreness.
Eleven young males performed 300 unilateral, maximal voluntary, eccentric actions with the musculus quadriceps femoris (30 degrees x s(-1)). Before and at regular intervals for 7 d after exercise, force-generating capacity was measured with maximal concentric knee extensions (60 degrees x s(-1)). Accumulation of radiolabeled (autologous) leukocytes was measured with scintigraphy. Biopsies from musculus vastus lateralis were obtained 0.5, 4, 8, 24, 96, and 168 h after exercise from both the exercised leg and the control leg. Muscle cross-sections were stained with antibodies against leukocytes (CD16 and CD68). Muscle soreness was rated on a visual analog scale.
Immediately after exercise, the subjects' ability to generate force was reduced by 47 +/- 5%. Muscle function recovered slowly and was not fully restored after 1 wk. Radiolabeled leukocytes accumulated in the muscles during the first hour (3-24 h) after exercise, and leukocytes were at the same time observed histologically, primarily in the endomysium and perimysium. A part of the accumulated radiolabeled leukocytes appeared to be located within local blood vessels. The highest numbers of CD16(+) and CD68(+) cells were found 4 and 7 d after exercise. There was a positive correlation between accumulation of radiolabeled leukocytes and muscle weakness measured 1-3 d after exercise (r = 0.8, P < 0.05) and, surprisingly, a negative correlation between radiolabeled leukocyte accumulation and muscle soreness (r = -0.96, P < 0.01).
Exercise-induced muscle damage initiated a rapid local inflammatory response that gradually increased over the next days. Halted recovery of muscle function was associated with local accumulation of leukocytes, whereas muscle soreness could not be explained by the presence of leukocytes.
In this study, we investigated the effect of water immersion on physical test performance and perception of fatigue/recovery during a 4-day simulated soccer tournament. Twenty high-performance junior male soccer players (age 15.9 +/- 0.6 years) played four matches in 4 days and undertook either cold-water immersion (10 +/- 0.5 degrees C) or thermoneutral water immersion (34 +/- 0.5 degrees C) after each match. Physical performance tests (countermovement jump height, heart rate, and rating of perceived exertion after a standard 5-min run and 12 x 20-m repeated sprint test), intracellular proteins, and inflammatory markers were recorded approximately 90 min before each match and 22 h after the final match. Perceptual measures of recovery (physical, mental, leg soreness, and general fatigue) were recorded 22 h after each match. There were non-significant reductions in countermovement jump height (1.7-7.3%, P = 0.74, eta(2) = 0.34) and repeated sprint ability (1.0-2.1%, P = 0.41, eta(2) = 0.07) over the 4-day tournament with no differences between groups. Post-shuttle run rating of perceived exertion increased over the tournament in both groups (P < 0.001, eta(2) = 0.48), whereas the perceptions of leg soreness (P = 0.004, eta(2) = 0.30) and general fatigue (P = 0.007, eta(2) = 0.12) were lower in the cold-water immersion group than the thermoneutral immersion group over the tournament. Creatine kinase (P = 0.004, eta(2) = 0.26) and lactate dehydrogenase (P < 0.001, eta(2) = 0.40) concentrations increased in both groups but there were no changes over time for any inflammatory markers. These results suggest that immediate post-match cold-water immersion does not affect physical test performance or indices of muscle damage and inflammation but does reduce the perception of general fatigue and leg soreness between matches in tournaments.
Twenty untrained male volunteers were required to run downhill for 45 minutes on a motor driven treadmill to induce muscle soreness. The volunteers took diclofenac or placebo before and for 72 hours after two runs 10 weeks apart, in a randomised double blind crossover design. Subjective soreness was assessed before and at intervals up to 72 hours after each run; venous blood samples, collected at the same time intervals, were used to estimate serum activities of creatine kinase, lactate dehydrogenase and aspartate aminotransferase and serum concentrations of creatinine and urea. Subjective soreness and the biochemical parameters increased after both runs, although the serum enzyme response to the second run was reduced. Diclofenac had no influence on the serum biochemical response to downhill running. Although overall soreness was not affected by diclofenac, individual soreness measurements were reduced by diclofenac at the first period of the study. These results suggest that diclofenac does not influence muscle damage, but may slightly reduce the associated soreness.
The vastus lateralis muscles of eleven male elite sprinters (17-28 years) were investigated in order to examine the impact of high tension anaerobic muscular work on muscle fibre fine structure. In an attempt to reproduce the training regimen six subjects ran 20 repetitions of 25 s on a treadmill with 2 min 35 s in between, at a speed corresponding to 86% of their personal best 200 m time. PAS-stained sections of biopsies taken approximately 2 h after training generally indicated glycogen depletion in type 1 and type 2B fibres. At the light microscopic level, no signs of inflammation or fibre rupture were observed. However, at the ultrastructural level, frequent abnormalities of the contractile material and the cytoplasmic organelles were detected. Z-band streaming, autophagic vacuoles and abnormal mitochondria were the most conspicuous observations. Control specimens from sprinters who did not perform the acute exercise routine also displayed structural deviations, although to a lesser degree. It is hypothesized that during sprint training the leg musculature is put under great mechanical and metabolic stress which causes the degenerative response reported here.
Delayed onset muscle soreness (DOMS) is a sensation of discomfort that occurs 1 to 2 days after exercise. The soreness has been reported to be most evident at the muscle/tendon junction initially, and then spreading throughout the muscle. The muscle activity which causes the most soreness and injury to the muscle is eccentric activity. The injury to the muscle has been well described but the mechanism underlying the injury is not fully understood. Some recent studies have focused on the role of the cytoskeleton and its contribution to the sarcomere injury. Although little has been confirmed regarding the mechanisms involved in the production of delayed muscle soreness, it has been suggested that the soreness may occur as a result of mechanical factors or it may be biochemical in nature. To date, there appears to be no relationship between the development of soreness and the loss of muscle strength, in that the timing of the two events is different. Loss of muscle force has been observed immediately after the exercise. However, by collecting data at more frequent intervals a second loss of force has been reported in mice 1 to 3 days post-exercise. Future studies with humans may find this second loss of force to be related to DOMS. The role of inflammation during exercise-induced muscle injury has not been clearly defined. It is possible that the inflammatory response may be responsible for initiating, amplifying, and/or resolving skeletal muscle injury. Evidence from the literature of the involvement of cytokines, complement, neutrophils, monocytes and macrophages in the acute phase response are presented in this review. Clinically, DOMS is a common but self-limiting condition that usually requires no treatment. Most exercise enthusiasts are familiar with its symptoms. However, where a muscle has been immobilised or debilitated, it is not known how that muscle will respond to exercise, especially eccentric activity.
Delayed onset muscle soreness is a common problem that can interfere with rehabilitation as well as activities of daily living. The purpose of this study was to test the impact of therapeutic massage, upper body ergometry, or microcurrent electrical stimulation on muscle soreness and force deficits evident following a high-intensity eccentric exercise bout. Forty untrained, volunteer female subjects were randomly assigned to one of three treatment groups or to a control group. Exercise consisted of high-intensity eccentric contractions of the elbow flexors. Resistance was reduced as subjects fatigued, until they reached exhaustion. Soreness rating was determined using a visual analog scale. Force deficits were determined by measures of maximal voluntary isometric contraction at 90 degrees of elbow flexion and peak torque for elbow flexion at 60 degrees/sec on a Cybex II isokinetic dynamometer. Maximal voluntary isometric contraction and peak torque were determined at the 0 hour (before exercise) and again at 24 and 48 hours postexercise. Treatments were applied immediately following exercise and again at 24 hours after exercise. The control group subjects rested following their exercise bout. Statistical analysis showed significant increases in soreness rating and significant decreases in force generated when the 0 hour was compared with 24- and 48-hour measures. Further analysis indicated no statistically significant differences between massage, microcurrent electrical stimulation, upper body ergometry, and control groups.
Perceived muscle soreness ratings, serum creatine kinase (CK) activity, and myoglobin levels were assessed in three groups of subjects following two 30-min exercise bouts of downhill running (-10 degrees slope). The two bouts were separated by 3, 6, and 9 wk for groups 1, 2, and 3, respectively. Criterion measures were obtained pre- and 6, 18, and 42 h postexercise. On bout 1 the three groups reported maximal soreness at 42 h postexercise. Also, relative increases in CK for groups 1, 2, and 3 were 340, 272, and 286%, respectively. Corresponding values for myoglobin were 432, 749, and 407%. When the same exercise was repeated, significantly less soreness was reported and smaller increases in CK and myoglobin were found for groups 1 and 2. For example, the percent CK increases on bout 2 for groups 1 and 2 were 63 and 62, respectively. Group 3 demonstrated no significant difference in soreness ratings, CK activities, or myoglobin levels between bouts 1 and 2. It was concluded that performance of a single exercise bout had a prophylactic effect on the generation of muscle soreness and serum protein responses that lasts up to 6 wk.
Introduction: Delayed onset muscle soreness (DOMS), which occurs after eccentric exercises, may cause some reduction in ability in sport activities. For this reason, numerous recovery strategies have been used in an attempt to control the inflammatory-type response. Physical modalities have demonstrated no effect on the alleviation of muscle soreness or other DOMS symptoms. Whole-body vibration (WBV) has been suggested as a viable warm-up in sport fields. However, there is a lack of scientific evidence to support the protective effects of WBV-Training (WBVT) on muscle damage. Material and Methods: Thirty-two healthy untrained volunteers randomly assigned into two groups: WBVT (n=15) and control (n=17). Subjects performed 6 sets of 10 maximal isokinetic (60°.s-1) eccentric contractions of knee extensors with dominant limb on a dynamometer. In the WBVT group before eccentric exercise, whole body vibration was applied using a vibratory platform (Power Plate, 35 Hz, 5 mm peak-to-peak amplitude), with 100° knee flexion for 60 seconds while no vibration was applied in the control group. DOMS criteria (serum creatine kinase (CK), pressure pain threshold (PPT), muscle soreness, thigh circumference and maximal voluntary isometric exertion) were recorded at baseline, immediately after, 1to 14 days postexercise. Results: WBVT group showed significant reduction of DOMS symptoms in terms of lower CK levels, less PPT, less muscle soreness and lower maximal isometric voluntary strength loss compared to the control group (P< 0.05) However, no significant effect on thigh circumference was evident (P> 0.05). Conclusions: The findings of this study showed that WBVT administered before eccentric exercise may control and prevent DOMS and enhance the quadriceps muscle activity. Further investigation should be undertaken to ascertain the effectiveness of WBVT in athletes.
Delayed onset muscle soreness (DOMS) is a sensation of discomfort that occurs 1 to 2 days after exercise. The soreness has been reported to be most evident at the muscle/tendon junction initially, and then spreading throughout the muscle. The muscle activity which causes the most soreness and injury to the muscle is eccentric activity. The injury to the muscle has been well described but the mechanism underlying the injury is not fully understood. Some recent studies have focused on the role of the cytoskeleton and its contribution to the sarcomere injury.
Although little has been confirmed regarding the mechanisms involved in the production of delayed muscle soreness, it has been suggested that the soreness may occur as a result of mechanical factors or it may be biochemical in nature. To date, there appears to be no relationship between the development of soreness and the loss of muscle strength, in that the timing of the two events is different. Loss of muscle force has been observed immediately after the exercise. However, by collecting data at more frequent intervals a second loss of force has been reported in mice 1 to 3 days post-exercise. Future studies with humans may find this second loss of force to be related to DOMS.
The role of inflammation during exercise-induced muscle injury has not been clearly defined. It is possible that the inflammatory response may be responsible for initiating, amplifying, and/or resolving skeletal muscle injury. Evidence from the literature of the involvement of cytokines, complement, neutrophils, monocytes and macrophages in the acute phase response are presented in this review.
Clinically, DOMS is a common but self-limiting condition that usually requires no treatment. Most exercise enthusiasts are familiar with its symptoms. However, where a muscle has been immobilised or debilitated, it is not known how that muscle will respond to exercise, especially eccentric activity.
Objective:
To compare the intensity of the upper versus lower rectus abdominis (RA) muscle activity provoked by each of two different abdominal exercises and to contrast the intensity of contraction elicited by two different abdominal exercises on each RA muscle portion.
Design:
Nonrandomized control trial.
Setting:
Kinesiology laboratory in a university medicine faculty.
Participants:
Convenience sample of 33 healthy volunteers. Subjects who had practiced endurance or strength training activities (1.5 hours 3 days a week for 3 years) and those who had not accomplished that criterion comprised a high and a low physical activity group, respectively. Each of these two groups was divided by the ability to perform the exercises into two subgroups: correct and incorrect performers (cp, ic).
Main outcome measure:
Average surface iEMG was compared between upper and lower RA and on each muscle portion performing curl-up (CU) and posterior pelvic tilt (PT) exercises. The coefficient of variation, a two-way analysis of variance, and the t test were calculated.
Results:
The upper RA showed significantly greater activity during performance of CU exercise by the cp subgroups of both high (t = 2.14302, 95%) and low (t = 2.35875, 95%) activity groups. Only the cp subgroup of the high activity group showed that PT was significantly more strenuous than CU exercise on lower RA (t = -2.06467, 95%).
Conclusions:
Among correct performers, CU produces greater activity on upper RA. For persons who have a high level of activity, PT is more strenuous than CU on lower RA. Among incorrect performers, either exercise indistinctly activates the muscle portions.
Delayed onset muscle soreness (DOMS) generally occurs between 24 and 72 hours after a bout of unaccustomed exercise that involves eccentric muscle action. In this review, a variety of aerobic and anaerobic activities are described emphasizing the eccentric component. It is suggested that the experience of severe DOMS can adversely impact various aspects of performance. During endurance events there may be a decrease in economy of movement, impairment of glycogen repletion and an alteration in biomechanical execution of a movement. Reductions in strength/power are also associated with severe DOMS. It is suggested that these changes might put an athlete at increased risk of injury. Although treatment is available to alleviate or prevent DOMS, the wisdom of routinely engaging in such a practice is questioned. Finally, it is noted that one bout of unaccustomed eccentrics results in some adaptation, which has a protective effect during subsequent bouts of eccentric exercise in that DOMS and other markers of muscle trauma are significantly reduced. Recommendations are made for dealing with DOMS at the initiation of an exercise program and during a regular season.
(C) 1992 National Strength and Conditioning Association
Background:
Many people stretch before or after engaging in athletic activity. Usually the purpose is to reduce risk of injury, reduce soreness after exercise, or enhance athletic performance. This is an update of a Cochrane review first published in 2007.
Objectives:
The aim of this review was to determine effects of stretching before or after exercise on the development of delayed-onset muscle soreness.
Search strategy:
We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to 10 August 2009), the Cochrane Central Register of Controlled Trials (2010, Issue 1), MEDLINE (1966 to 8th February 2010), EMBASE (1988 to 8th February 2010), CINAHL (1982 to 23rd February 2010), SPORTDiscus (1949 to 8th February 2010), PEDro (to 15th February 2010) and reference lists of articles.
Selection criteria:
Eligible studies were randomised or quasi-randomised studies of any pre-exercise or post-exercise stretching technique designed to prevent or treat delayed-onset muscle soreness (DOMS). For the studies to be included, the stretching had to be conducted soon before or soon after exercise and muscle soreness had to be assessed.
Data collection and analysis:
Risk of bias was assessed using The Cochrane Collaboration's 'Risk of bias' tool and quality of evidence was assessed using GRADE. Estimates of effects of stretching were converted to a common 100-point scale. Outcomes were pooled in fixed-effect meta-analyses.
Main results:
Twelve studies were included in the review. This update incorporated two new studies. One of the new trials was a large field-based trial that included 2377 participants, 1220 of whom were allocated stretching. All other 11 studies were small, with between 10 and 30 participants receiving the stretch condition. Ten studies were laboratory-based and other two were field-based. All studies were exposed to either a moderate or high risk of bias. The quality of evidence was low to moderate.There was a high degree of consistency of results across studies. The pooled estimate showed that pre-exercise stretching reduced soreness at one day after exercise by, on average, half a point on a 100-point scale (mean difference -0.52, 95% CI -11.30 to 10.26; 3 studies). Post-exercise stretching reduced soreness at one day after exercise by, on average, one point on a 100-point scale (mean difference -1.04, 95% CI -6.88 to 4.79; 4 studies). Similar effects were evident between half a day and three days after exercise. One large study showed that stretching before and after exercise reduced peak soreness over a one week period by, on average, four points on a 100-point scale (mean difference -3.80, 95% CI -5.17 to -2.43). This effect, though statistically significant, is very small.
Authors' conclusions:
The evidence from randomised studies suggests that muscle stretching, whether conducted before, after, or before and after exercise, does not produce clinically important reductions in delayed-onset muscle soreness in healthy adults.
Unlabelled:
Evidence suggests large diameter afferents, presumably in response to centrally mediated changes, augment the mechanical allodynia or hyperalgesia seen in delayed onset muscle soreness (DOMS) conditions. Healthy males aged 18 to 30 (n = 16) performed eccentric exercise eliciting DOMS in the tibialis anterior muscle of a randomly assigned exercised leg. The contralateral leg served as a control. Mechanosensitivity was assessed on the exercised and control legs prior to and 24 hours postexercise via pressure pain thresholds (PPTs). PPTs were assessed at the muscle site, and at a distant segmentally related site, either without vibration or with vibration concurrently applied to the distant muscle, segmentally related, or control extra-segmentally related site. Participants completed a 6-point Likert scale providing a subjective measure of DOMS 5 days postexercise. Baseline mechanosensitivity was not significantly different at any site between the exercised and control legs prior to the exercise. Soreness ratings were higher 24 to 48 hours postexercise (P < .05), and baseline PPTs at the exercised legs muscle site decreased postexercise (P < .001). On day 1 following exercise, segmentally related site PPTs reduced significantly when vibration was applied concurrently to the DOMS affected tibialis anterior muscle (P < .04) compared to baseline mechanosensitivity or extrasegmental control vibration.
Perspective:
Further evidence is presented by this article indicating that large diameter afferents, presumably via centrally mediated mechanisms, augment the mechanical hyperalgesia seen in DOMS conditions. Future research examining eccentric activity in individuals with likely centrally sensitized conditions may be warranted.
The purpose of this study was to determine if pomegranate juice supplementation improved the recovery of skeletal muscle strength after eccentric exercise in subjects who routinely performed resistance training. Resistance trained men (n = 17) were randomized into a crossover design with either pomegranate juice or placebo. To produce delayed onset muscle soreness, the subjects performed 3 sets of 20 unilateral eccentric elbow flexion and 6 sets of 10 unilateral eccentric knee extension exercises. Maximal isometric elbow flexion and knee extension strength and muscle soreness measurements were made at baseline and 2, 24, 48, 72, 96, and 168 hours postexercise. Elbow flexion strength was significantly higher during the 2- to 168-hour period postexercise with pomegranate juice compared with that of placebo (main treatment effect; p = 0.031). Elbow flexor muscle soreness was also significantly reduced with pomegranate juice compared with that of placebo (main treatment effect; p = 0.006) and at 48 and 72 hours postexercise (p = 0.003 and p = 0.038, respectively). Isometric strength and muscle soreness in the knee extensors were not significantly different with pomegranate juice compared with those using placebo. Supplementation with pomegranate juice attenuates weakness and reduces soreness of the elbow flexor but not of knee extensor muscles. These results indicate a mild, acute ergogenic effect of pomegranate juice in the elbow flexor muscles of resistance trained individuals after eccentric exercise.
: The aim of this study was to test the hypothesis that vibration treatment reduces delayed-onset muscle soreness and swelling and enhances recovery of muscle function after eccentric exercise.
: A randomized crossover design was used. Fifteen young men performed ten sets of six maximal eccentric contractions of the elbow flexors with the right arm for one occasion and the left arm for the other occasion separated by 4 wks. One arm received a 30-min vibration treatment at 30 mins after and 1, 2, 3, and 4 days after the exercise (treatment group), and the other arm did not receive any treatment (control group). The order of the treatment and control conditions and the use of the dominant and nondominant arms were counterbalanced among subjects. Changes in indirect markers of muscle damage were compared between arms by a two-way repeated-measures analysis of variance.
: Compared with the control group, the treatment group showed significantly (P < 0.05) less development and faster reduction in delayed-onset muscle soreness at 2 to 5 days after exercise. The recovery of range of motion was significantly (P < 0.05) faster for the treatment than for the control group. However, no significant effects on the recovery of muscle strength and serum creatine kinase activity were evident. Immediately after the vibration treatment, a significant (P < 0.05) decrease in the magnitude of delayed-onset muscle soreness and muscle strength and an increase in pressure pain threshold and range of motion were found.
: These results showed that the vibration treatment was effective for attenuation of delayed-onset muscle soreness and recovery of range of motion after strenuous eccentric exercise but did not affect swelling, recovery of muscle strength, and serum creatine kinase activity.
The purpose of this pragmatic preliminary analysis was to examine the effectiveness of a cocoa-based protein and carbohydrate prototype drink on skeletal muscle damage and perceived soreness after exhaustive exercise. A repeated-measures experimental design was used. Common biomarkers indicative of skeletal muscle damage included creatine kinase (CK), urinary isoprostanes and inflammatory markers (IL-6, IL-8, C-Reactive Protein [CRP]). Self-reported perception of postexercise soreness was also evaluated. Seven men participated in an exercise session consisting of a 30-minute run on a declined treadmill (-10% grade). Running speed was adjusted accordingly so that participants consistently maintained 75% maximal heart rate. Drinks were ingested immediately after exercise, 2 hours postexercise, and before bed. Blood draws were sampled 30, 60, 120, and 360 minutes postexercise; urine was collected 24 and 48 hours postexercise. A perceived soreness questionnaire was administered 24 and 48 hours postexercise. The test drink had no effect on IL-6, CK, IL-8, CRP, or urinary isoprostanes (p > 0.05). However, the drink decreased the change in perceived soreness from 24 to 48 hours (p = 0.03). Consuming the drink after exercise resulted in a mean change of 2.6 +/- 6 compared to 13.7 +/- 10 for the control. In summary, the drink was effective in decreasing the level of self-reported perceived soreness after exhaustive exercise.
Dietary supplementation with polyphenols,particularly ellagitannins, may attenuate the muscular damage experienced after eccentric exercise, producing delayed-onset muscle soreness. The purpose of this study was to determine whether ellagitannin supplementation from Wonderful variety pomegranate extract (POMx) improved recovery of skeletal muscle strength after eccentric exercise.
Recreationally active males were randomized into a crossover design with either pomegranate extract (POMx) or placebo (PLA), each given during a period of 9 d.To produce delayed-onset muscle soreness, subjects performed two sets of 20 maximal eccentric elbow flexion exercises with one arm.Maximal isometric elbow flexion strength and muscle soreness as well as serum measures of creatine kinase, myoglobin, interleukin 6, and C-reactive protein were made at baseline and 2, 24, 48, 72, and 96 h after exercise.
With both treatments, strength was similarly reduced 2 h after exercise (i.e., 72% of baseline), and recovery of strength was incomplete after 96 h (i.e., 91% of baseline).However, strength was significantly higher in POMx compared with that in PLA at 48 h (85.4% +/- 2.5% and 78.3% +/- 2.6%, P = 0.01) and 72 h (88.9% +/- 2.0% and 84.0% +/- 2.0%, P = 0.009) after exercise. Serum markers of inflammation and muscle damage did not provide insight regarding possible mechanisms.
Supplementation with ellagitannins from pomegranate extract significantly improves recovery of isometric strength 2-3 d after a damaging eccentric exercise.
Attempts to reduce or eliminate delayed-onset of muscle soreness are important as this condition is painful and debilitating. The purpose of this study was to examine the effectiveness of whole-body vibration (WBV) massage and stretching exercises at reducing perceived pain among untrained men. Sixteen adult men (age, 36.6 +/- 2.1 yr) volunteered to perform a strenuous exercise session consisting of resistance training and repeated sprints. Subjects were randomly assigned to 1 of 2 recovery groups: a group performing WBV stretching sessions or a stretching group performing static stretching without vibration. Both groups performed similar stretches, twice per day for 3 days after the workout. The vibration group performed their stretches on the iTonic platform (frequency, 35 Hz; amplitude, 2 mm). Perceived pain was measured at 12, 24, 48, and 72 hours postworkout. Statistical analyses identified a significantly lower level of reported perceived pain at all postworkout measurement times among the WBV group (p < 0.05). No difference existed at the preworkout measurement time. The degree of attenuation of pain ranged from 22-61%. These data suggest that incorporating WBV as a recovery/regeneration tool may be effective for reducing the pain of muscle soreness and tightness after strenuous training.
To examine soft tissue release (STR) as an intervention for delayed onset muscle soreness (DOMS).
A mixed-subjects experimental design was used. Participants performed 4 x 20 eccentric elbow extensions at 80% of 1RM. Participants received either STR (50%) or no treatment (50%). DOMS measurements were taken before the elbow extensions and at 0, 24, and 48 h afterwards.
The study was conducted at the University of Essex exercise physiology laboratory.
Twenty male participants, unaccustomed to strength conditioning, completed the study.
DOMS was evaluated using relaxed joint angle (RJA), active range of motion (AROM), passive range of motion (PROM), and arm girth measurements. Soreness ratings were measured using a 100 mm visual analogue scale (VAS).
In both conditions there were post-DOMS task increases in VAS ratings (p < 0.0001) and arm girths (p < 0.0001), and decreases in RJA (p < 0.0001), AROM (p < 0.0001), and PROM (p < 0.0001). STR group VAS scores were higher immediately (p < 0.01) and 48 h after treatment (p < 0.005). There were no other between-group differences and none of the measurements returned to baseline levels by 48 h.
STR exacerbates the DOMS sensation yet does not seem to improve the rate of recovery during the first 48 h.
The complete role of the myotendinous junction is discussed in this article. The morphology and function of the junction, typical injuries occurring at this region, delayed-onset muscle soreness, and muscle strain injury are described. Muscle strain injury is covered in detail, including characterization, treatment, and prevention. Clinical information is conveyed as well as basic science study results pertinent to the clinical situation.
It is well documented in animal and human research that unaccustomed eccentric muscle action of sufficient intensity and/or duration causes disruption of connective and/or contractile tissue. In humans, this appears to be associated with the sensation of delayed onset muscle soreness (DOMS). During the late 1970's, it was proposed that this sensation of soreness might be associated with the acute inflammatory response. However, subsequent research failed to substantiate this theory. The present article suggests that the results of much of the research concerning DOMS reflect events typically seen in acute inflammation. Similarities between the two events include: the cardinal symptoms of pain, swelling, and loss of function; evidence of cellular infiltrates, especially the macrophage; biochemical markers such as increased lysosomal activity and increased circulating levels of some of the acute phase proteins; and histological changes during the initial 72 h. In the final section of this paper, a theoretical sequence of events is proposed, based on research involving acute inflammation and DOMS.
Immediately following unaccustomed exercise, particularly that with eccentric contractions, there is evidence of injury to skeletal muscle fibers: a) disruption of the normal myofilament structures in some sarcomeres, observable with both light and electron microscope and b) loss of intramuscular proteins (e.g., creatine kinase enzymes) into the plasma, indicating damage to sarcolemma. This pathology is probably responsible for the temporary reductions in muscle force and delayed-onset soreness that can occur following eccentric exercise. The mechanisms underlying this injury are not known, although loss of intracellular Ca2+ homeostasis could play a primary role. In other experimental muscle injury models, elevated [Ca2+]i appears to cause release of muscle enzymes through activation of phospholipase A2, which in turn could induce injury to sarcolemma through production of leukotrienes and prostaglandins, through free O2 radical formation (in the subsequent lipoxygenase and cyclooxygenase reactions), and/or through release of detergent lysophospholipids. On the other hand, the mechanism responsible for the rapid damage to myofibrils caused by increased [Ca2+]i is unknown. Regardless of the cause(s), the initial and early events in the injury process are autogenetic; i.e., they are indigenous to the muscle cells and occur before phagocytic cells enter the injury site.
Novel, unaccustomed exercise has been shown to result in temporary, repairable skeletal muscle damage. After exhaustive endurance exercise, muscle damage can be produced by metabolic disturbances associated with ischaemia. Extensive disruption of muscle fibres also occurs after relatively short term eccentric exercise where high mechanical forces are generated. Biopsies taken after repetitive eccentric muscle actions have revealed broadening, streaming and, at times, total disruption of Z-discs. Muscles that develop active tension eccentrically also become sore, lose inherent force-producing capability, and show a marked release of muscle proteins into the circulation. Because creatine kinase (CK) is found almost exclusively in muscle tissue, it is the most common plasma marker of muscle damage. Despite the universal use of CK as a marker, several factors with regard to efflux and clearance remain unexplained. Also the large intersubject variability in response to exercise complicates its interpretation.
Damage progresses in the postexercise period before tissues are repaired. However, the mechanism to explain exercise-induced muscle damage and repair is not well defined. Among the factors that may influence the damage and repair processes are calcium, lysosomes, connective tissue, free radicals, energy sources, and cytoskeletal and myofibrillar proteins.
Physical conditioning results in an adaptation such that all indicators of damage are reduced following repeated bouts of exercise. Recently, investigators have suggested that the prophylactic effect of training may be due to performance of a single initial exercise bout. Following a second bout of exercise performed 1 to 6 weeks after the first bout, there is a reduction in morphological alterations and performance decrements and a profoundly reduced elevation in plasma CK levels. Several hypotheses have been presented to explain the repeated bout or rapid training effect. Stress-susceptible fibres may be eliminated or susceptible areas within a fibre may undergo necrosis and then regenerate. These regenerated fibres, along with adaptations in the connective tissue, may provide greater resistance to further insult.
Musculotendinous injuries are responsible for a significant proportion of injuries incurred by athletes. Many of these injuries are preventable. Importantly, musculotendinous injuries have a high incidence of recurrence. Thus, muscle injury prevention is advocated by coaches and trainers. Yet, most of the recommendations for muscle injury prevention are attempted by athletes and taught by coaches without supporting scientific evidence. This paper reviews the mechanics of muscular injury, associated and predisposing factors, and methods of prevention with a review of the supporting research and rationale for these methods with an emphasis on warm-up, stretching and strengthening. Muscles that are capable of producing a greater force, a faster contraction speed and subjected to a greater stretch are more likely to become injured. Many factors have been associated with muscular injury. From current research, some conclusions and recommendations for muscle injury prevention can be made. Overall and muscular conditioning and nutrition are important. Proper training and balanced strengthening are key factors in prevention of musculotendinous injuries as well. Warm-up and stretching are essential to preventing muscle injuries by increasing the elasticity of muscles and smoothing muscular contractions. Improper or excessive stretching and warming up can, however, predispose to muscle injury. Much research is still needed in this important aspect of sports medicine.
The perception of muscle soreness is probably due to the activation of free nerve endings around muscle fibers. These nerve endings serve as receptors of noxious stimuli associated with muscle damage. Modulation of soreness may take place at the peripheral receptor sites or at a central or spinal level. This multilevel modulation may explain the large intersubject variation in the perception of muscle soreness. The type of exercise that produces the greatest degree of soreness is eccentric exercise, although isometric exercise may also result in soreness. Eccentric exercise has been shown to produce muscle cellular damage and decrements in motor performance as well. Although training is considered to prevent muscle soreness, even trained individuals will become sore following a novel or unaccustomed exercise bout. Thus, training is specific to the type of exercise performed. Our laboratories have shown that the performance of a single exercise bout will have an effect on a subsequent similar bout given up to 6 weeks later. Thus, when a second bout of downhill running was given to subjects 6 weeks after the first bout, with no intervening exercise, less soreness developed, and muscle damage was estimated to be reduced. The explanation for this long-lasting prophylactic or "training effect" is currently under investigation in our laboratories.
In this study 11 subjects performed exercise resulting in delayed onset muscular soreness in m. gastrocnemius with one leg, the experimental leg. The other leg served as control. Pre-exercise and 24, 48 and 72 h postexercise, soreness perception, resting EMG level of m. gastrocnemius, and volume and skin temperature of both legs were measured, and a leukocyte count was performed. Perception of soreness in m. gastrocnemius reported 24, 48, and 72 h postexercise was not accompanied by an increase in resting EMG level. This result indicates that soreness perception is not related to a tonic localized spasm in sore muscles. A rise in volume of the experimental leg relative to volume of the control leg was found 24, 48, and 72 h postexercise (P less than 0.05). It is suggested that the volume rise is due to edema formation in the experimental leg and that this edema formation is responsible for soreness perception. Since granulocytosis was not found, the hypothesis that edema formation reflects muscle inflammation is not substantiated.
Perceived muscle soreness ratings, serum creatine kinase (CK) activity, and myoglobin levels were assessed in three groups of subjects following two 30-min exercise bouts of downhill running (-10 degrees slope). The two bouts were separated by 3, 6, and 9 wk for groups 1, 2, and 3, respectively. Criterion measures were obtained pre- and 6, 18, and 42 h postexercise. On bout 1 the three groups reported maximal soreness at 42 h postexercise. Also, relative increases in CK for groups 1, 2, and 3 were 340, 272, and 286%, respectively. Corresponding values for myoglobin were 432, 749, and 407%. When the same exercise was repeated, significantly less soreness was reported and smaller increases in CK and myoglobin were found for groups 1 and 2. For example, the percent CK increases on bout 2 for groups 1 and 2 were 63 and 62, respectively. Group 3 demonstrated no significant difference in soreness ratings, CK activities, or myoglobin levels between bouts 1 and 2. It was concluded that performance of a single exercise bout had a prophylactic effect on the generation of muscle soreness and serum protein responses that lasts up to 6 wk.
Skeletal muscle blood flow was measured before, during and after short application of different forms of massage using the local 133Xenon washout method for determination of blood flow. During maneouvres with tapotement (hacking) an increase in blood flow comparable to exercise hyperemia was observed, and this increase was ascribed to repetitive contractions. A prolonged hyperemia found after tapotement was ascribed to the traumatic procedure. During and after petrissage (kneading) the tissue perfusion did not change significantly. It is uncertain whether the reported changes in blood flow are related to therapeutic effects of massage, but the squeezing effect of petrissage might be important for lymphatic drainage.
Delayed-onset muscular soreness (DOMS), the sensation of pain and stiffness in the muscles that occurs from 1 to 5 d following unaccustomed exercise, can adversely affect muscular performance, both from voluntary reduction of effort and from inherent loss of capacity of the muscles to produce force. This reduction in performance is temporary; permanent impairment does not occur. A number of clinical correlates are associated with DOMS, including elevations in plasma enzymes, myoglobinemia, and abnormal muscle histology and ultrastructure; exertional rhabdomyolysis appears to be the extreme form of DOMS. Presently, the best treatment for DOMS appears to be muscular activity, although the sensation again returns following the exercise. Training for the specific contractile activity that causes DOMS reduces the soreness response. The etiology and cellular mechanisms of DOMS are not known, but a number of hypotheses exist to explain the phenomenon. The following model may be proposed: 1) high tensions (particularly those associated with eccentric exercise) in the contractile/elastic system of the muscle result in structural damage; 2) cell membrane damage leads to disruption of Ca++ homeostasis in the injured fibers, resulting in necrosis that peaks about 2 d post-exercise; and 3) products of macrophage activity and intracellular contents accumulate in the interstitium, which in turn stimulate free nerve endings of group-IV sensory neurons in the muscles leading to the sensation of DOMS.
Contraction-induced injury results in the degeneration and regeneration of muscle fibers. Of the three types of contractions--shortening (concentric), isometric, and lengthening (eccentric)--injury is most likely to occur and the severity of the injury is greatest during lengthening contractions. The magnitude of the injury to muscle fibers may be assessed by direct measures of cellular and ultrastructural damage; by indirect measures of changes in enzyme efflux, calcium influx, ratio of oxidized to reduced glutathione, and force development; and, in human beings, by reports of muscle soreness. The sequence of events includes an initial injury that is primarily mechanical and a secondary metabolic, or biochemical, injury that peaks 1 to 3 days after the injurious contractions. The recovery from contraction-induced injury is usually complete within 30 days. Repeated exposures to protocols of lengthening contractions result in "trained" muscles that are not injured by the protocol that previously caused injury.
This study investigated whether the two heads of Biceps Brachii could be functionally differentiated during rapid supination movements with different degrees of elbow flexion, shoulder axial rotation and load. Surface electromyograms, recorded from the long and short heads of Biceps Brachii, were utilised to identify changes in the intensity of muscle contraction. Based upon an analysis of sixteen subjects, the results indicated that joint position (muscle length), but not load, significantly (p < 0.05) influenced the relationship between the contraction intensities of the two heads. Specifically, increasing the length of the Biceps Brachii promoted increased activation of the long head in relation to the short head in producing rapid supination motions. It was concluded that functional differentiation within the two heads of Biceps Brachii was present in motions involving its distal insertion.