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Exercise Technique: The Landmine Row
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Purpose:
This study investigated the differences between selected physical attributes and ball release speed in slower and faster male and female elite pace bowlers.
Methods:
Twelve physical attributes and ball release speed were retrospectively analyzed from 63 male and 31 female elite pace bowlers over the course of 5 seasons. Pace bowlers were categorized as either fast (>122.9 km/h, males and >97.8 km/h, females) or slow (<122.9 km/h, males and <97.8 km/h, females) for each sex. Differences in physical attributes between slower and faster bowling groups were compared using Cohen d effect sizes.
Results:
Faster pace bowlers displayed differences in isometric midthigh-pull peak force (d = 0.25, males and d = 0.68, females) and relative peak force (d = 0.62, males and d = 0.77, females). Faster male pace bowlers displayed differences in relative (d = 0.61) and absolute (d = 0.39) countermovement jump heights. Faster female pace bowlers displayed differences in 1-repetition-maximum bench-pull strength (d = 0.45) and run-of-3 performance (relative average, d = 1.22; relative best, d = 1.12; average, d = 0.49; and best, d = 0.40).
Conclusions:
Anaerobic dominant physical attributes appear to be important in both male and female pace bowlers. The contribution of these physical attributes to ball release speed appears to differ slightly between males and females. Lower-body strength (males and females), lower-body power (males), relative anaerobic capacities (females), and upper-body strength (females) appear to distinguish between slower and faster elite pace bowlers.
Accentuated eccentric loading (AEL) employs heavier load magnitudes in eccentric actions than concentric actions of complete stretch-shortening cycles. In doing so, unique neuromuscular and molecular responses are expected to result in acute post-activation performance enhancements, as evidenced by increased movement velocity or power. Improvements are dependent upon load selection, which varies across exercises, such as jumps and bench press throws (eccentric: 20-40 kg or 20-30% of body mass; concentric: body mass only), and squats and bench press (eccentric: 77.3-120% One-Repetition Maximum (1-RM); concentric: 30-90% 1-RM). The efficacy of AEL is dependent upon the concentric load used, which in turn is influenced by the magnitude of the eccentric load. Greater strength relative to body mass may enable the maintenance of technique and pacing during AEL, necessary for resultant performance enhancements, particularly when using eccentric loads exceeding the individual’s concentric 1-RM. Before prescribing AEL practitioners should consider: training experience, strength relative to body mass, the particular exercise, AEL application method, and the magnitude of both eccentric and concentric loads. Thus, the aims of this brief review are to describe: 1) neuromuscular and molecular constructs of AEL; 2) acute effects of AEL; 3) chronic effects of AEL; 4) loading considerations; 5) practical applications.
This review aimed to perform a meta-analysis examining the following: (a) acute effects of adopting an internal focus vs. external focus of attention on muscular strength; and (b) long-term effects of adopting an internal focus vs. external focus of attention during resistance training on gains in muscular strength. We searched through five databases to find eligible studies. Random-effects meta-analyses of standardized mean differences were conducted to analyze the data. Ten studies were included. In the meta-analysis for the acute effects, there was a significant positive effect of external focus on muscular strength (standardized mean difference: 0.34; 95% confidence interval: 0.22, 0.46). In the meta-analysis for the long-term effects, there was no significant difference between training with an internal focus and external focus on muscular strength gains (standardized mean difference: 0.32; 95% confidence interval: –0.08, 0.73). In the subgroup analysis for lower-body exercises, we found a significant positive effect of training with an external focus on muscular strength gains (standardized mean difference: 0.47; 95% confidence interval: 0.07, 0.87). In summary, our findings indicate an acute increase in muscular strength when utilizing an external focus of attention. When applied over the long-term, using an external focus of attention may also enhance resistance training-induced gains in lower-body muscular strength.
Attentional focus strategies refer to the use of cues or other stimuli to enhance an individual’s concentration for the purpose of improving performance within a given task. PURPOSE: To examine the effects of an internal (INT), external proximal (EPr), and external distal (ED) method of attentional focus on motor unit excitation and repetitions-to-failure (RTF) during submaximal bench press performance. METHODS: Twenty-five recreationally-active males and females completed a one-repetition maximum (1RM) bench press test, followed by three days of submaximal testing at 85% 1RM to muscular failure. For each submaximal day, a specific attentional focus strategy was given by auditory cues (i.e., INT, EPr, ED) with the individual instructed to focus solely on the cue. Motor unit recruitment of the anterior deltoid, pectoralis major, and triceps brachii was measured, via electromyography (EMG), for each repetition for all interventions. RESULTS: Results indicated no differences for motor unit excitation (chest: p=0.59; triceps: p=0.50; deltoids: p=0.17) or RTF (p=0.89) among the three conditions. The INT cue, as compared to EPr and ED, elicited a ~7-10% average increase in pectoralis major motor unit excitation, despite an average of one less repetition. All effect sizes were deemed small or trivial, except for RTF between INT and ED which elicited a moderate effect size (ES=0.55). CONCLUSIONS: These findings support previous literature demonstrating increases in motor unit excitation with an internal attentional focus. However, this strategy may place a greater demand on the targeted musculature to complete a given task; thus, decreasing performance.
Introduction
Assessment of scapular kinematics and the dynamics of the scapulohumeral rhythm (SHR) would be important for understanding pathologies of the shoulder and to inform treatment. Our aim in this study was to evaluate the SHR and scapular kinematics in patients with a rotator cuff tear (RCT), compared to a control group with healthy shoulders using image-matching techniques.
Materials and Methods
The shoulder kinematics of large or massive RCT patients were evaluated and compared to a control group with healthy shoulders. Radiographic surveillance was performed throughout the full range of external rotation and scapular plane abduction. Computed tomography imaging of the shoulder complex was performed, with three-dimensional image reconstruction and matching to the radiographs to measure three-dimensional positions and orientations. SHR and angular values of the scapula were measured.
Results
Scapular external rotation in the late phase of external rotation movement was greater in the RCT group than in the control group ( p < 0.05), but with no difference in the SHR. During scapular plane abduction, there were significant differences in SHR, scapular posterior tilt and scapular upward rotation between the RCT and control group ( p < 0.05).
Conclusions
Regarding clinical relevance, this study clarified the differences of SHR and angular values of the scapula between the RCT and control group. These results underline the importance of assessment the SHR and scapular kinematics in individuals with a RCT. RCT is associated with specific compensation in the kinematics of the scapula and SHR during external rotation and scapular plane abduction, which could inform treatment.
This study describes the contemporary practices of strength and conditioning coaches in professional soccer. Fifty-two strength and conditioning coaches from professional leagues across 18 countries completed an online survey, consisting of 45 questions, with eight sections: (a) background information, (b) muscular strength and power development, (c) speed development, (d) plyometrics, (e) flexibility development, (f) physical testing, (g) technology use, and (h) programing. A frequency analysis was used to assess and report responses to fixed response questions, and thematic-analysis used for open-ended questions to create clear, identifiable and distinct themes. All strength and conditioning coaches were educated to degree level or higher, 65% held strength and conditioning certifications and 54% held soccer coaching certifications. Concentric (100%) and eccentric (98%) modes of resistance were the most commonly prescribed, whereas the squat (including variations)
(52%) was deemed the most important exercise for soccer players. Hang clean (33%) and multiple hops/lunges (89%) were the most programed Olympic weightlifting and plyometric exercises. Global Positioning Systems (94%) were the most utilized technology-based equipment. Time, scheduling and fixtures were the biggest issues faced, which made it difficult to periodize training programs and apply appropriate training loads. Furthermore, strength and conditioning coaches would like to further integrate technology to comprehensively monitor and test players, while also believing that technology will continue to be developed and integrated in the future. Strength and conditioning coaches from professional soccer can use the information from this study to review current practices and also provide ideas for diversifying or modifying future practices.
The aim of this study was to compare kinetics, muscle activation and performance during resistance exercises between internal focus attention instructions, external focus attention instructions and control condition. Thirty (n = 30, mean age = 21.40 ± 0.93 years old) healthy men were recruited as participants and were asked to perform resistance exercises in three conditions; i) internal focus, ii) external focus and iii) control (no focus attention instruction). Participants performed 10RM squat and deadlift assessment in which kinetics, muscle activation and number of repetitions completed were recorded and analyzed during the exercises. Findings of this study revealed that external focus attention instruction produced greater force production and number of repetitions completed while at the same time lower muscle activity compared to the internal focus conditions. To conclude, external focus attention instructions were suggested to be adopted during resistance training due to its effectiveness to make movement more economic while producing greater performance in which will be more advantages for future adaptations.
Background:
We investigated the feasibility of a 16-week supervised heavy resistance training program with weekly undulating periodization for individuals with persistent non-specific low-back pain (LBP).
Methods:
Twenty-five adults with persistent non-specific LBP participated in this mixed methods feasibility study. Participants trained a whole-body program consisting of squat, bench press, deadlift and pendlay row two times per week for 16 weeks. We assessed pain intensity, pain-related disability, pain self-efficacy and one-repetition maximum strength at baseline, 8 weeks and 16 weeks. Three focus group interviews were conducted at the end of the program. Linear mixed models were used to assess changes in outcomes, and the qualitative data was assessed using systematic text condensation.
Results:
We observed clinically meaningful reductions in pain intensity after 8 and 16 weeks of training. The mean difference on the numeric pain rating scale (0-10) in the last 2 weeks from baseline to 8 weeks was 2.6 (95% CI: 1.8-3.6) and from baseline to 16 weeks 3.4 (95% CI: 2.5-4.4). In addition, there were improvements in pain-related disability (3.9, 95% CI: 2.3-5.5), pain self-efficacy (7.7, 95% CI: 5.4-10.1) and muscle strength. In the focus group interviews, participants talked about challenges regarding technique, the importance of supervision and the advantages of periodizing the training. Perceived benefits were improved pain, daily functioning, energy level and sleep, and changes in views on physical activity.
Conclusion:
Periodized resistance training with weekly undulating periodization is a feasible training method for this group of individuals with persistent non-specific LBP. A randomized clinical trial should assess the efficacy of such an intervention.
Trial registration:
clinicaltrials.gov/ Identifier - NCT04284982, Registered on February 24th 2020.
Shattock, K and Tee, JC. Autoregulation in resistance training: A comparison of subjective versus objective methods. J Strength Cond Res XX(X): 000-000, 2020-Autoregulation (AR) is a resistance training periodization approach that adjusts training prescription in response to individual rates of athlete adaptation. AR training prescription can make use of either subjective (rating of perceived exertion [RPE]) or objective (barbell velocity) intensity descriptors. The aim of this research was to compare the efficacy of these 2 approaches in improving sport-specific physical performance measures. Using a randomized crossover design, 20 amateur rugby union players completed two 6-week blocks of training with training intensity prescribed using either objective velocity-based (VB) (measured using a wearable accelerometer device) or objective RPE-based intensity prescriptions. Training volume was matched for both groups while training intensity was equivalent but prescribed using either VB or RPE measures. Performance measurements were countermovement jump (CMJ), 1 repetition maximum back squat and bench press, and 10-, 20-, and 40-m sprint. Testing was conducted before and immediately after each training block. The likelihood that observed changes in performance measures were meaningful was assessed using magnitude-based decisions. Both training programs induced practically meaningful improvements in CMJ (VB most likely +8.2, ±1.1%; RPE likely +3.8, ±0.9%), back squat (VB most likely +7.5, ±1.5%; RPE possibly +3.5, ±1.8%), and bench press (VB most likely +7.7, ±2.1%; RPE possibly +3.8, ±0.9%). Changes in sprint test performance were very likely trivial for both programs. Objective AR programming resulted in larger improvements in CMJ (likely 4.2, ±1.2%), squat (likely 3.7, ±1.5%) performance, and bench press (possibly 3.7, ±1.5%) performance. Autoregulation periodization improved strength and CMJ, but not sprint performance. Autoregulation effects are augmented through the use of objective intensity prescription.
Aims:
This study aimed to analyze the effect of verbal instruction on myoelectric activity (EMG) of the elbow flexors and shoulder extensors muscles during seated row exercise at 70%1RM, in trained and untrained individuals.
Methods:
The study sample comprised of seven males (21 ± 1.9 years) who had not practiced resistance training for at least one year (untrained group), and eight males (23 ± 2.6 years) who had regularly practice strength training for 2.4 ± 0.7 years (trained group). All individuals performed the seated row exercise with 70%1RM in conditions with and without verbal instruction. The EMG of the latissimus dorsi, teres major, posterior deltoid, triceps brachii long head and biceps brachii were measured.
Results:
There was no effect of verbal instruction on EMG at any muscle analyzed, for both groups. There was a difference between groups only for the teres major and triceps brachii (p < 0.05). Untrained individuals had greater myoelectric activity in teres major and triceps brachii long head muscles compared to the trained group during the exercise.
Traditional training progressions have involved changes in volume, intensity and density (amount of work per period of time). An alternative, recently popular, and action specific (sport, work, activities of daily living) functional training progression involves alterations in the complexity of movement. Increased complexity modulates the technical difficulty level of the exercise. Technical challenges can include more task specific, multi-segmental, multi-planar, double task (cognitive and physical), non-cyclical, unilateral, or alternating execution of exercises, changes in movement velocity, instability and visual deprivation.
The use of chain or elastic band-resisted variable resistance has become popular in the training of athletes. A number of studies have investigated the utilization of variable resistance vs. traditional resistance training on both acute and chronic performance measures. However, the mechanisms of the observed outcome measures are not fully understood. This review aims to propose a four-part theory regarding the bases by which chain and elastic band-based variable resistance have been shown to be effective. Additionally, it compares methodologies in studies utilizing variable resistance and provides practitioners with recommendations on the use of variable resistance based on the current literature.
Purpose:
The purpose of this study was to evaluate muscular adaptations between low-, moderate-, and high-volume resistance training (RT) protocols in resistance-trained men.
Methods:
Thirty-four healthy resistance-trained men were randomly assigned to 1 of 3 experimental groups: a low-volume group (1SET) performing 1 set per exercise per training session (n = 11); a moderate-volume group (3SET) performing 3 sets per exercise per training session (n = 12); or a high-volume group (5SET) performing 5 sets per exercise per training session (n = 11). Training for all routines consisted of three weekly sessions performed on non-consecutive days for 8 weeks. Muscular strength was evaluated with 1 repetition maximum (RM) testing for the squat and bench press. Upper-body muscle endurance was evaluated using 50% of subjects bench press 1RM performed to momentary failure. Muscle hypertrophy was evaluated using B-mode ultrasonography for the elbow flexors, elbow extensors, mid-thigh and lateral thigh.
Results:
Results showed significant pre-to-post intervention increases in strength and endurance in all groups, with no significant between-group differences. Alternatively, while all groups increased muscle size in most of the measured sites from pre-to-post intervention, significant increases favoring the higher volume conditions were seen for the elbow flexors, mid-thigh, and lateral thigh.
Conclusion:
Marked increases in strength and endurance can be attained by resistance-trained individuals with just three, 13-minute weekly sessions over an 8-week period, and these gains are similar to that achieved with a substantially greater time commitment. Alternatively, muscle hypertrophy follows a dose-response relationship, with increasingly greater gains achieved with higher training volumes.
The present study investigated the effects of different intensities of resistance training (RT) on elbow flexion and leg press one-repetition maximum (1RM) and muscle cross-sectional area (CSA). Thirty men volunteered to participate in an RT programme, performed twice a week for 12 weeks. The study employed a within-subject design, in which one leg and arm trained at 20% 1RM (G20) and the contralateral limb was randomly assigned to one of the three conditions: 40% (G40); 60% (G60), and 80% 1RM (G80). The G20 started RT session with three sets to failure. After G20 training, the number of sets was adjusted for the other contralateral limb conditions with volume-matched. CSA and 1RM were assessed at pre, post-6 weeks, and post-12 weeks. There was time effect for CSA for the vastus lateralis (VL) (8.9%, 20.5%, 20.4%, and 19.5%) and elbow flexors (EF) (11.4%, 25.3%, 25.1%, and 25%) in G20, G40, G60, and G80, respectively (p > .05). G80 showed higher CSA than G20 for VL (19.5% vs. 8.9%) and EF (25% vs. 11.4%) at post-12 weeks (p < .05). There was time effect for elbow flexion and unilateral leg press strength for all groups post-12 weeks (p < .05). However, the magnitude of increase was higher in G60 and G80. In conclusion, when low to high intensities of RT are performed with volume-matched, all intensities were effective for increasing muscle strength and size; however, 20% 1RM was suboptimal in this regard, and only the heavier RT intensity (80% 1RM) was shown superior for increasing strength and CSA compared to low intensities.
The purpose of this study was to investigate the effects of using an internal versus external focus of attention during resistance training on muscular adaptations. Thirty untrained college-aged men were randomly assigned to an internal focus group (INTERNAL) that focused on contracting the target muscle during training (n = 15) or an external focus group (EXTERNAL) that focused on the outcome of the lift (n = 15). Training for both routines consisted of 3 weekly sessions performed on non-consecutive days for 8 weeks. Subjects performed 4 sets of 8–12 repetitions per exercise. Changes in strength were assessed by six repetition maximum in the biceps curl and isometric maximal voluntary contraction in knee extension and elbow flexion. Changes in muscle thickness for the elbow flexors and quadriceps were assessed by ultrasound. Results show significantly greater increases in elbow flexor thickness in INTERNAL versus EXTERNAL (12.4% vs. 6.9%, respectively); similar changes were noted in quadriceps thickness. Isometric elbow flexion strength was greater for INTERNAL while isometric knee extension strength was greater for EXTERNAL, although neither reached statistical significance. The findings lend support to the use of a mind–muscle connection to enhance muscle hypertrophy.
Accentuated eccentric loading (AEL) prescribes eccentric load magnitude in excess of the concentric prescription using movements that require coupled eccentric and concentric actions, with minimal interruption to natural mechanics. This method has been theorized to potentiate concentric performance through higher eccentric loading and, thus, higher concentric force production. There is also evidence for favorable chronic adaptations, namely shifts to faster myosin heavy chain isoforms and changes in IIx-specific muscle cross-sectional area. However, research concerning the acute and chronic responses to AEL is inconclusive, likely due to inconsistencies in subjects, exercise selection, load prescription, and method of providing AEL. Therefore, the purpose of this review is to summarize: (1) the magnitudes and methods of AEL application; (2) the acute and chronic implications of AEL as a means to enhance force production; (3) the potential mechanisms by which AEL enhances acute and chronic performance; and (4) the limitations of current research and the potential for future study.
THE USE OF VERTICALLY LOADED EXERCISES, SUCH AS THE BACK SQUAT, DEADLIFT, AND OLYMPICSTYLE LIFTS, ARE COMMONLY PRESCRIBED BY STRENGTH AND CONDITIONING PROFESSIONALS TO ENHANCE THE PHYSICAL QUALITIES OF ATHLETES. THESE METHODS HAVE BEEN SUPPORTED AS EFFECTIVE MEANS, MAINLY FOR NOVICE SUBJECTS, BUT THEIR EFFECTIVENESS AND TRANSFER HAS BEEN QUESTIONED IN MORE ADVANCED ATHLETES AND IN TRANSFER TO SPECIFIC PHYSICAL QUALITIES. THE EFFECTIVENESS OF VERTICALLY LOADED EXERCISE TO ENHANCE SPRINTING SPEED AND CHANGE OF DIRECTION (COD) SPEED IS EQUIVOCAL IN ADVANCED ATHLETES, AND THE USE OF HORIZONTALLY LOADED MOVEMENT MAY HAVE BETTER TRANSFER FOR SPRINTING SPEED AND COD SPEED.
WEIGHTLIFTING MOVEMENTS AND THEIR DERIVATIVES MAY BE IMPLEMENTED IN A SEQUENCED PROGRESSION THROUGHOUT THE TRAINING YEAR TO OPTIMIZE THE DEVELOPMENT OF AN ATHLETE’S STRENGTH, RATE OF FORCE DEVELOPMENT, AND POWER OUTPUT. WEIGHTLIFTING MOVEMENTS AND THEIR DERIVATIVES CAN BE PROGRAMMED EFFECTIVELY BY CONSIDERING THEIR FORCE–VELOCITY CHARACTERISTICS AND PHYSIOLOGICAL UNDERPINNINGS TO MEET THE SPECIFIC TRAINING GOALS OF RESISTANCE TRAINING PHASES IN ACCORDANCE WITH THE TYPICAL APPLICATION OF PERIODIZED TRAINING PROGRAMS.
STRENGTH AND CONDITIONING PROFESSIONALS COMMONLY DEPEND ON EVIDENCE TO GUIDE "WHAT THEY COACH" (E.G., PROGRAMMING), BUT THE SAME CANNOT ALWAYS BE SAID FOR THEIR APPROACH TO "HOW THEY COACH" (E.G., INSTRUCTION). CONSEQUENTLY, PROFESSIONALS HAVE ADOPTED THE CONVENTIONAL VIEW THAT COACHING IS MORE ART THAN SCIENCE, DESPITE THE FACT THAT THERE ARE DECADES OF RESEARCH ELUCIDATING THE SCIENCE UNDERPINNING THIS SOCALLED ART. IN LIGHT OF THIS GAP, THIS ARTICLE WILL DELVE INTO THIS UNDERPINNING SCIENCE AND PROVIDE AN EVIDENCEBASED FRAMEWORK FOR INSTRUCTION AND CUEING THROUGH THE LENS OF LINEAR SPEED DEVELOPMENT.
The purpose of this paper was to systematically review the current literature and elucidate the effects of total weekly resistance training (RT) volume on changes in measures of muscle mass via meta-regression. The final analysis comprised 34 treatment groups from 15 studies. Outcomes for weekly sets as a continuous variable showed a significant effect of volume on changes in muscle size (P = 0.002). Each additional set was associated with an increase in effect size (ES) of 0.023 corresponding to an increase in the percentage gain by 0.37%. Outcomes for weekly sets categorised as lower or higher within each study showed a significant effect of volume on changes in muscle size (P = 0.03); the ES difference between higher and lower volumes was 0.241, which equated to a percentage gain difference of 3.9%. Outcomes for weekly sets as a three-level categorical variable (<5, 5-9 and 10+ per muscle) showed a trend for an effect of weekly sets (P = 0.074). The findings indicate a graded dose-response relationship whereby increases in RT volume produce greater gains in muscle hypertrophy.
Background:
In this study, we investigated the effects of resistance training protocols with different loads on muscle hypertrophy and strength.
Methods:
Twenty-one participants were randomly assigned to 1 of 3 (n = 7 for each) resistance training (RT) protocols to failure: High load 80 % 1RM (8-12 repetitions) (H group), low load 30 % 1RM (30-40 repetitions) (L group) and a mixed RT protocol (M group) in which the participants switch from H to L every 2 weeks. RT consisted of three sets of unilateral preacher curls performed with the left arm 3 times/week with 90 s rest intervals between sets. The right arm served as control. Maximum voluntary contraction (MVC) of the elbow flexors (elbow angle: 90°) and rate of force development (RFD, 0-50, 50-100, 100-200 and 200-300 ms) were measured. Cross-sectional area (CSA) of the elbow flexors was measured via magnetic resonance imaging (MRI). All measurements were conducted before and after the 8 weeks of RT (72-96 h after the last RT). Statistical evaluations were performed with two-way repeated measures (time × group).
Results:
After 8 weeks of 3 weekly RT sessions, significant increases in the left elbow flexor CSA [H: 9.1 ± 6.4 % (p = 0.001), L: 9.4 ± 5.3 % (p = 0.001), M: 8.8 ± 7.9 % (p = 0.001)] have been observed in each group, without significant differences between groups. Significant changes in elbow flexor isometric MVC have been observed in the H group (26.5 ± 27.0 %, p = 0.028), while no significant changes have been observed in the M (11.8 ± 36.4 %, p = 0.26) and L (4.6 ± 23.9 %, p = 0.65) groups. RFD significantly increased during the 50-100 ms phase in the H group only (p = 0.049).
Conclusions:
We conclude that, as long as RT is conducted to failure, training load might not affect muscle hypertrophy in young men. Nevertheless, strength and RFD changes seem to be load-dependent. Furthermore, a non-linear RT protocol switching loads every 2 weeks might not lead to superior muscle hypertrophy nor strength gains in comparison with straight RT protocols.
Coaching instructions and cues are methods of verbal communication that can be used specifically by strength and conditioning and sport coaches to focus an athletes’ attention for enhanced sport performance. Specifically, there is evidence to support that providing athletes external or neutral attentional focus instruction and cues can enhance sprinting speed. The purpose of this article is to translate the findings from the literature regarding the benefits and effects of coaching instructions and cues on sprint performance and to provide general recommendations for enhancing athlete sprint capabilities through the administration of appropriate verbal communications.
Purpose:
This study evaluates whether focusing on using specific muscles during bench press can selectively activate these muscles.
Methods:
Altogether 18 resistance-trained men participated. Subjects were familiarized with the procedure and performed one-maximum repetition (1RM) test during the first session. In the second session, 3 different bench press conditions were performed with intensities of 20, 40, 50, 60 and 80 % of the pre-determined 1RM: regular bench press, and bench press focusing on selectively using the pectoralis major and triceps brachii, respectively. Surface electromyography (EMG) signals were recorded for the triceps brachii and pectoralis major muscles. Subsequently, peak EMG of the filtered signals were normalized to maximum maximorum EMG of each muscle.
Results:
In both muscles, focusing on using the respective muscles increased muscle activity at relative loads between 20 and 60 %, but not at 80 % of 1RM. Overall, a threshold between 60 and 80 % rather than a linear decrease in selective activation with increasing intensity appeared to exist. The increased activity did not occur at the expense of decreased activity of the other muscle, e.g. when focusing on activating the triceps muscle the activity of the pectoralis muscle did not decrease. On the contrary, focusing on using the triceps muscle also increased pectoralis EMG at 50 and 60 % of 1RM.
Conclusion:
Resistance-trained individuals can increase triceps brachii or pectarilis major muscle activity during the bench press when focusing on using the specific muscle at intensities up to 60 % of 1RM. A threshold between 60 and 80 % appeared to exist.
The process of strength–power training and the subsequent adaptation is a multi-factorial process. These factors range from the genetics and morphological characteristics of the athlete to how a coach selects, orders, and doses exercises and loading patterns. Consequently, adaptation from these training factors may largely relate to the mode of delivery, in other words, programming tactics. There is strong evidence that the manner and phases in which training is presented to the athlete can make a profound difference in performance outcome. This discussion deals primarily with block periodization concepts and associated methods of programming for strength–power training within track and field.
In recent years, it has become popular for athletes and recreational trainers to perform resistance training with the addition of bands and chains. In this paper, we consider the advantages of manipulating an exercise to match the resistance provided with the force capabilities of the lifter, which generally change throughout the movement. We explain that bands and chains can be used to manipulate a variety of exercises that have the potential to enhance performance in sport and in many daily tasks. Whilst there are many similarities between the use of bands and chains for resistance training, we note that there are key differences
and discuss the biomechanics of each material separately. In particular, we discuss that chains provide resistance primarily in the vertical plane and the resistance is linearly related to the displacement of the barbell. In contrast, bands can be set up to produce substantial horizontal forces in addition to the primary resistance force that often acts in the vertical direction. Also, research has demonstrated that bands provide a resistance force that is related in a curvilinear fashion to the displacement of the barbell. After introducing the main biomechanical features associated with each type of resistance material, we present findings from the strength and conditioning literature that has demonstrated the potential for bands and chains to improve the stimulus associated with strength and power training. At present, a more compelling evidence base has emerged for the use of bands in resistance training, particularly with regard to the development of power.
It is not known whether this asymmetry reflects the greater number of studies conducted with bands or is influenced by methodological differences between studies. However, we also discuss the possibility that different inertial properties of bands compared with chains may make the former a more effective choice for the development of power. We hope that exercise professionals will benefit from this knowledge and obtain insight into how an understanding of biomechanical principles can assist with prescribing contemporary training regimes.
Variable resistance training (VRT) methods improve the rate of force development (RFD), coordination between antagonist and synergist muscles, the recruitment of motor units, and reduce the drop in force produced in the sticking region. However, the beneficial effects of long-term VRT on maximal strength both in athletes and untrained individuals have been much disputed. The purpose of this study was to compare in a meta-analysis the effects of a long-term (>= 7 weeks) VRT program using chains or elastic bands and a similar constant resistance program in both trained adults practicing different sports and untrained individuals. Intervention effect sizes were compared among investigations meeting our selection and inclusion criteria using a random effects model. The published studies considered were those addressing VRT effects on the one repetition maximum (1RM). Seven studies involving 235 subjects fulfilled the selection and inclusion criteria. VRT led to a significantly greater mean strength gain (weighted mean difference: 5.03 kg; 95% CI: 2.26-7.80 kg; Z = 3.55; P < 0.001) than the gain recorded in response to conventional weight training. Long-term VRT training using chains or elastic bands attached to the barbell emerged as an effective evidence-based method of improving maximal strength both in athletes with different sports backgrounds and untrained subjects.
Abstract
Objectives. - Strength and speed are 2 major factors that determine a swimmer’s sprint performance, especially swim sprint performance and swim starts. This study identified and examined variables that determine the influence of maximal strength performance on different swim performance styles and distances in trained adolescent swimmers.
Equipment and Methods. - Twenty-one regional swimmers (12 males and 9 females, 17.5 ± 2 years; mass: 69.5 ± 11.4 kg; height: 177.3 ± 10.1 m) volunteered to take part in the present study. One-Repetition-Maximums (1RM) in the back squat, deadlift, bent-over row and sit-up were used to determine maximum strength. Squat jump (SJ) and countermovement jump (CMJ) were evaluated to determine speed-strength performance. Swim performances of 15 to 100 meters in freestyle, breaststroke and backstroke were measured in a 25-m indoor pool. Pearson correlation analysis was used to assess the relationships between strength and power variables and swim variables.
Results. - Strong negative correlations between leg strength (1RM squat), speed strength (SJ and CMJ) and swim performance were found in this investigation, especially for short distances (up to 25 m, r=-0.75 to -0.94, p<0.05). Additionally, moderate to mostly strong correlations (r=-0.37 to -0.85, p<0.05) were found between the strength tests of the upper extremities, and non-uniform correlations were found for the trunk strength test (r=-0.05 to -0.68) and swim performance.
Conclusion. - The maximal strength parameters of the upper and lower extremities and maximal trunk strength are good predictors of performance in sprint swimming in trained adolescent swimmers in different disciplines.
While suspension devices have gained in popularity in the fitness industry, there is limited information on the effects of hand-grip orientations during pulling movements as compared to traditional methods. Objective: To investigate the electromyographical activity of the primary and secondary musculature during a pronated and supinated grip inverted row while using a suspension training device. Twenty individuals volunteered to participate in the current study. Electromyographical (EMG) values were obtained from the latissimus dorsi (LD), posterior deltoid (PD), middle trapezius (MT), and biceps brachii (BB). Subjects performed four variations of a traditional inverted row using two handgrips: pronated row (IR), pronated suspended-row (SR), supinated row (IRsup), and supinated suspended-row (SRsup). In terms of the LD, SR provided the highest activation. However the only difference was within IRsup, which was significantly lower than both pronated-grip rows (i.e., IR and SR). SRsup resulted in significantly greater (p < 0.05) activation of the BB when compared to the remaining exercises. SR provided significantly greater (p < 0.05) PD activity, while EMG activity of the MT was significantly lower in SRsup compared to all other movements. The results indicate that significant differences exist in muscular activity during hand-grip variations as well as with the use of an instability device. The major findings were the decreases seen in PD and MT when using a supinated grip. As a result, suspension devices may provide an acute suitable alternative to traditional bodyweight training.
The purpose of this paper was to conduct a systematic review and meta-analysis of studies that compared muscle hypertrophy and strength gains between resistance training protocols employing very low (VLL < 30% of 1-repetition maximum (RM) or >35RM), low (LL30%–59% of 1RM, or 16–35RM), moderate (ML60%–79% of 1RM, or 8–15RM), and high (HL ≥ 80% of 1RM, or ≤7RM) loads with matched volume loads (sets × repetitions × weight). A pooled analysis of the standardized mean difference for 1RM strength outcomes across the studies showed a benefit favoring HL vs. LL and vs. ML and favoring ML vs. LL. The LL and VLL results showed little difference. A pooled analysis of the standardized mean difference for hypertrophy outcomes across all studies showed no differences between training loads. Our findings indicate that when the volume load is equal between conditions, the highest loads induce superior dynamic strength gains. Alternatively, hypertrophic adaptations were similar irrespective of the load magnitude.
Novelty: Training with higher loads elicits greater gains in 1RM muscle strength when compared to lower loads, even when the volume load is equal between conditions. Muscle hypertrophy is similar irrespective of the magnitude of the load, even when the volume load is equal between conditions.
Collins, KS, Klawitter, LA, Waldera, RW, Mahoney, SJ, and Christensen, BK. Differences in muscle activity and kinetics between the goblet squat and landmine squat in men and women. J Strength Cond Res XX(X): 000-000, 2021-Squat exercise variations are widely used and extensively researched. However, little information exists on the goblet squat (GBS) and landmine squat (LMS) and differences between men and women. This study investigated the differences in muscle activity and kinetics between the GBS and the LMS in 16 men and 16 women. Five repetitions of each squat type were performed loaded at 30% of their body mass. Vertical and anteroposterior ground reaction forces for the eccentric and concentric phases and peak vertical force were recorded with a force plate. Electromyographic (EMG) signals were recorded for the vastus medialis (VM), vastus lateralis (VL), semitendinosus (ST), and biceps femoris (BF). Normalized mean EMG values and ground reaction forces were analyzed with repeated measures analysis of variance (p < 0.05). Significant main effects for squat condition and sex were found. The LMS reduced activity in the quadriceps (VM and VL) muscles and vertical forces, while increasing posterior horizontal forces. In the LMS, men showed decreased ST activity, whereas women had decreased BF activity. Women exhibited greater quadriceps activity in both the GBS and LMS and greater ST in the LMS. Women also produced greater eccentric vertical force in both the GBS and LMS and less posterior horizontal forces in the LMS. The LMS may be useful to balance hamstring to quadriceps activity, increase horizontal loading, and reduce vertical loading. Conversely, the GBS can better target quadriceps activity and increase vertical loading. Sex differences should be considered for training programs that include the GBS and LMS.
Rowing exercises are widely used in resistance training. However, from an efficacy and safety standpoint, few science-based recommendations about proper ergonomics performing different rowing variations are currently available. Therefore, the purpose of this study was to examine the electromyographical (EMG) differences between four variations during the dynamic performance of the bent-over row (BOR) exercise: BOR in inclined bench with 90o shoulder abduction (B/AB); BOR in inclined bench with maximum shoulder adduction (B/AD); standing BOR with 90o shoulder abduction (S/AB); standing BOR with maximum shoulder adduction (S/AD). A cross-sectional preliminary study of repeated measures was designed. three young and healthy participants with previous experience in resistance training were recruited from university students of Sport Sciences Degree (mean ± SD age: 21.67 ± 1.21 years; body mass: 75.13 ± 7.00 kg; IMC: 26.15 ± 1.63 kg/m2; % body fat= 9.72 ± 2.41% height: 1.69 ± 9.43 m; training experience: 4.64 ± 1.39 years). Muscle activity was measured using surface EMG in six lumbar, dorsal, and shoulder muscles: posterior deltoid (PD), latissimus dorsi (LD), upper trapezius (UT), middle trapezius (MT), lumbar portion of erector spinae (LES) and thoracic portion erector spinae (TES). Results showed that the two variations based on standing postures (S/AB and S/AD) caused
greater EMG responses both on shoulder and lumbar and dorsal muscles. However, importantly, participants had the highest EMG activity on target muscles (deltoid and trapezius muscles) when performing the BOR in a shoulder abduction position (B/AB and S/AB), independent of whether they were, or were not, working with the bench. Thus, considering that the mild activity showed from the lumbar and dorsal back muscles when performing the bench variations would denote lower spine loads, we can conclude that, from an ergonomic standpoint, the use of the bench should be indicated when performing the BOR exercise. However, this is only a preliminary conclusion and the subject needs future analysis.
Context:
Scapular retraction exercises are often prescribed to enhance scapular stabilization.
Objectives:
To investigate the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT) activities, and UT/MT and UT/LT ratios during scapular retraction exercise with elastic resistance at different shoulder abduction angles.
Design:
Descriptive laboratory study.
Setting:
Biomechanical analysis laboratory.
Patients or other participants:
Thirty-five asymptomatic individuals.
Main outcome measures:
Surface electromyography was used to evaluate UT, MT, and LT activities during the scapular retraction exercise at 0º, 45º, 90º, and 120º shoulder abductions.
Results:
The mean muscle activity ranged from 15.8%-54.7% maximum voluntary isometric contraction (MVIC) for UT, 30.5%-51.6% MVIC for MT, 21.4%-25.5% MVIC for LT. A significant "muscle×angle" interaction was found (p<0.001). Post hoc analysis revealed that the MT was significantly more activated than UT and LT during both retraction at 0º (p<0.001; p=0.01, respectively) and 120º (p=0.03; p=0.002, respectively). During retraction at 45º and 90º, the LT generated significantly lower activity than the UT (p=0.02; p=0.03, respectively) and MT (p<0.001; p=0.002, respectively). Besides, UT/MT and UT/LT ratios during retraction at 0º were significantly lower than 45º (p=0.03; p=0.001, respectively) and 90º (p<0.001; p<0.001, respectively). Retraction at 90º resulted significantly higher UT/LT ratio than 45º (p=0.004) and 120º (p=0.004).
Conclusions:
Due to lower UT activity relative to MT, retraction at 0º, 45º, and 120º can be preferred in early shoulder training or rehabilitation. Additionally, retraction at 90º was the most effective exercise in activating entire trapezius muscle parts.
This study describes the contemporary practices of strength and conditioning (S&C) coaches in professional cricket. Thirty-three S&C coaches working with international and professional club teams across seven countries completed an online survey. The survey consisted of 45 questions (35 fixed responses and 10 open-ended), with eight sections: (a) background information, (b) muscular strength and power development, (c) speed development, (d) plyometrics, (e) flexibility development, (f) physical testing, (g) technology use, and (h) programing. Most S&C coaches were educated to degree level (97%) or higher, with 91% of degrees being in a sports science related field. Whereas, 73% held S&C and 40% cricket coaching certifications. Isometric type resistance training exercises (94%) were frequently programed by S&C coaches, with squats and deadlifts (including variations) deemed the most important strength development exercises. Ratings of perceived exertion (58%) was most used for determining set loads. Hang clean (64%) and multiple hops/lunges (85%) were the most prescribed Olympic weightlifting and plyometric exercises. Speed gates (85%) were the most used technology-based equipment. Open-ended questions revealed, 45% of S&C coaches believed time constraints, scheduling and fixtures are the main issues faced in their role. Position specific demands (61%) was the predominant method used for individualizing players training strategies. The information presented in this study is valuable for those pursuing or currently working as a S&C coach in professional cricket to align, compare and explain their practices. Furthermore, will provide insight for the wider athlete support team (i.e., sports coaches, physiotherapists) on the practices of S&C coaches.
Neuromuscular training programs that incorporate lower extremity strengthening, plyometric exercises, balance training, and movement retraining are recommended for anterior cruciate ligament injury prevention; however, there is a need to improve their effectiveness. The purpose of this study was to examine how athletes' attentional focus during training influences the effects of an 8-week neuromuscular training program on hip strength, single-leg landing mechanics, and hop performance. Sixty-six male athletes were randomly allocated to a group that trained with an internal focus, a group that trained with an external focus, or a control group. All athletes completed testing before (baseline) and after (posttesting) the 8-week period. Isokinetic hip strength, hip and knee kinematics and ground reaction forces during landing, and hop distance were examined as part of this study. Analysis of covariance was used to compare posttesting outcomes among the groups while accounting for group differences in baseline performance. The neuromuscular training program resulted in improved hip abduction strength, reduced hip adduction and internal rotation motion during landing, and increased hop distance for athletes who trained with an external focus. However, the program did not seem to influence hip strength, landing kinematics, or hop performance for athletes who trained with an internal focus. Our findings indicate that male athletes may benefit from completing a neuromuscular training program with an external focus vs. an internal focus. Trainers, coaches, and clinicians should consider using instructions that promote an external focus when implementing neuromuscular training programs with male athletes.
Kubo, K, Ikebukuro, T, and Yata, H. Effects of 4, 8, and 12 repetition maximum resistance training protocols on muscle volume and strength. J Strength Cond Res XX(X): 000-000, 2020-The purpose of this study was to determine skeletal muscle adaptations (strength and hypertrophy) in response to volume-equated resistance training with divergent repetition strategies. Forty-two men were randomly assigned to 4 groups: higher load-lower repetition group performing 4 repetition maximum (RM) for 7 sets (4RM, n = 10), intermediate load-intermediate repetition group performing 8RM for 4 sets (8RM, n = 12), lower load-higher repetition group performing 12RM for 3 sets (12RM, n = 10), and nonexercising control group (CON, n = 10). The volume of the pectoralis major muscle (by magnetic resonance imaging) and 1RM of the bench press were measured before and after 10 weeks of training (2 times per week). No significant difference was observed in the relative increase in the muscle volume among the 4RM, 8RM, and 12RM groups. The relative increase in 1RM was significantly lower in the 12RM group than in the 4RM group (p = 0.029) and the 8RM group (p = 0.021). The relative increase in 1RM was significantly correlated with that in the muscle volume in the 12RM group (r = 0.684, p = 0.042), but not in the 4RM (r = -0.265, p = 0.777) or 8RM (r = -0.045, p = 0.889) groups. These results suggest that the increase in muscle size is similar among the 3 training protocols when the training volume was equated, whereas the increase in muscle strength is lower with the 12RM protocol than the other protocols.
This study examined the reliability and validity of three methods of estimating the one-repetition maximum (1RM) during the free-weight prone bench pull exercise. Twenty-six men (22 rowers and four weightlifters) performed an incremental loading test until reaching their 1RM, followed by a set of repetitions-to-failure. Eighteen participants were re-tested to conduct the reliability analysis. The 1RM was estimated through the lifts-to-failure equations proposed by Lombardi and O'Connor, general load-velocity (L-V) relationships proposed by Sánchez-Medina and Loturco and the individual L-V relationships modelled using four (multiple-point method) or only two loads (two-point method). The direct method provided the highest reliability (coefficient of variation [CV] = 2.45% and intraclass correlation coefficient [ICC] = 0.97), followed by the Lombardi's equation (CV = 3.44% and ICC = 0.94), and no meaningful differences were observed between the remaining methods (CV range = 4.95-6.89% and ICC range = 0.81-0.91). The lifts-to-failure equations overestimated the 1RM (3.43-4.08%), the general L-V relationship proposed by Sánchez-Medina underestimated the 1RM (-3.77%), and no significant differences were observed for the remaining prediction methods (-0.40-0.86%). The individual L-V relationship could be recommended as the most accurate method for predicting the 1RM during the free-weight prone bench pull exercise.
The barbell row exercise is one of a number of rowing exercises used to enhance strength and muscle development in the upper back, posterior shoulder girdle, and shoulder joint muscles, respectively. It often is taught relatively early in a strength and conditioning program because of its relative simplicity. Its utility as a safe and effective strength development tool is predicated on sound instruction, effective supervision, and proper execution.
THE LANDMINE SINGLE-LEG ROMANIAN DEADLIFT (LANDMINE SL RDL) IS CLASSIFIED AS A UNILATERAL LOWER-BODY MOVEMENT THAT CAN BE USED TO BUILD STABILITY, STRENGTH, AND POWER THROUGHOUT AN ATHLETE'S POSTERIOR CHAIN AND CORE. THERE ARE CURRENTLY LITTLE TO NO ARTICLES PUBLISHED THAT DISCUSS THE USE OF LANDMINE EXERCISES. CONSEQUENTLY, THE PURPOSE OF THIS ARTICLE IS THREE-FOLD TO: (A) PROVIDE A DETAILED DISCUSSION ON HOW TO EXECUTE THE LANDMINE SL RDL PROPERLY, (B) DISCUSS THE BENEFITS OF THIS MOVEMENT, AND (C) DISCUSS HOW COACHES AND STRENGTH AND CONDITIONING PROFESSIONALS CAN INTEGRATE IT INTO PRACTICE. D.
Background:
The most commonly recommended initial treatment for multidirectional instability is a rehabilitation program. Although there is evidence to support the effect of conservative management on this condition, the published literature provides little information on the exercise parameters of such programs. In addition, current published rehabilitation programs for multidirectional instability do not focus on scapula stability or exercise drills into functional and sports-specific positions, which are often important aspects to consider in this patient population.
Methods:
The aim of this paper (Part 1) is to outline the first two stages of a six-stage rehabilitation program for the conservative management of multidirectional instability with a focus on scapula control and exercise drills into functional positions.
Results and conclusions:
This clinical protocol is currently being tested for efficacy as part of a randomized controlled trial (Australian New Zealand Clinical Trials Registry #ACTRN12613001240730). The information in this paper and additional online supplementary files will provide therapists with adequate detail to replicate the rehabilitation program in the clinical setting.
The purpose of the study was to compare core muscle activation in 3 different row exercises (free-weight bent-over row, seated cable row and machine row) performed unilaterally and bilaterally, at matched effort levels. 15 resistance-trained men (26.0±4.4 years, 81.0±9.5 kg, 1.81±0.07 m) performed the exercises in randomized order. For erector spinae and multifidus, EMG activities in unilateral machine- and cable row were 60-63% and 74-78% of the bilateral performance (P≤0.036). For external oblique, the EMG activities recorded during bilateral exercises were 37-41% of the unilateral performance (P≤0.010). In unilateral cable- and machine rows, the EMG activities in external oblique and multifidus were 50-57% and 70-73% of the free-weight row (P≤0.002). In bilateral free-weight row, EMG activity in erector spinae was greater than bilateral machine- (+34%, P=0.004) and unilateral free-weight rows (+12%, P=0.016). For rectus abdominis there were no significant differences between conditions. In conclusion, 1) free-weight row provided greater EMG activity in erector spinae (bilaterally and unilaterally) and multifidus (unilaterally) than machine row; 2) unilateral performance of exercises activated the external oblique more than bilateral performance, regardless of exercise; and 3) generally bilateral performance of exercises provided higher erector spinae and multifidus EMG activity compared to unilateral performance.
© Georg Thieme Verlag KG Stuttgart · New York.
Over the past 15 years, research on focus of attention has consistently demonstrated that an external focus (i.e., on the movement effect) enhances motor performance and learning relative to an internal focus (i.e., on body movements). This article provides a comprehensive review of the extant literature. Findings show that the performance and learning advantages through instructions or feedback inducing an external focus extend across different types of tasks, skill levels, and age groups. Benefits are seen in movement effectiveness (e.g., accuracy, consistency, balance) as well as efficiency (e.g., muscular activity, force production, cardiovascular responses). Methodological issues that have arisen in the literature are discussed. Finally, our current understanding of the underlying mechanisms of the attentional focus effect is outlined, and directions for future research are suggested.