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Thermographic assessment of skin response to strength training in young participants
Abstract
Thermography is often used to determine the effect of training and the risk of injury following training. However, thermograms taken at different intervals following exercise give different results. To determine the hourly variation in skin temperature in the upper and lower body immediately after strength training. A secondary objective was to determine if there are any bilateral differences for each area and moment of temperature recording. A longitudinal study design was employed to study the evolution of skin temperature over 8 h following an exercise protocol consisting of four sets of ten repetitions of the bench press, the leg press, the flat bench cable fly, and the leg extension. The sample consisted of fourteen physically active university students. Thermograms were recorded with a T335 FLIR® infrared camera (FLIR® Systems, Sweden). The temperatures from 24 regions of interest (ROIs) were obtained from the 78 anatomical regions provided by the Termotracker® software (ThermoHuman, Spain). A repeated-measures analysis of variance with planned repeated contrast tests was used to determine the effect of successive changes in temperature. Significant differences in body temperature over time were found in both the upper and lower body. No significant bilateral differences were found. Thermal images taken after training are affected by when they are taken, as the results show that in the trunk, the arms, and the legs the skin temperature drops significantly immediately after the exercise, then increases to the initial pre-exercise temperature and continues to increase in most cases.
... Thermography provides information about the skin temperature of the analyzed body regions. The variation in skin temperature is related to physiological processes that occur in response to training stimuli 28 . Additionally, thermal asymmetries between body hemispheres have shown their utility in identifying injury risk markers 15,16 . ...
The demanding nature of elite football requires players to be closely monitored to ensure optimal performance and minimize injury risk. This study aimed to evaluate the relationship between physical demands, skin temperature, and well-being status in 30 elite football players over a 12-week competitive period. Thermography assessments, weekly Well-being questionnaires, and daily training and match load recordings were used to gather data. Results indicated that along the microcycles there was a decrease in high-intensity accelerations and decelerations distance completed, while maintaining other high-intensity actions. Furthermore, it was found that high-intensity movements contribute to the generation of thermal asymmetries in the thighs; the adductor thermal asymmetry showed a positive relationship with stress and muscle soreness, the knee thermal asymmetry had a positive relationship with fatigue and a negative relationship with rest and quality of rest, and finally the hamstrings muscles exhibited significant differences between the thermal asymmetry groups, with the high asymmetry completing less high intensity actions than the low asymmetry group. In conclusion, this study highlights the interconnections between physical demands, skin temperature, and well-being in elite football players and provides valuable insights for coaches and trainers in their efforts to optimize performance and health.
... The demand for rasterstereography as a noninvasive method is increasing to reduce the burden of the healthcare system and reduce follow-up radiological measurements 10 . Similarly, IRT is providing valuable results in monitoring the body's response to external stimuli such as cryotherapy 11 , whole-body vibration 12 , and strength training 13 . ...
The demand for noninvasive methods to assess postural defections is increasing because back alterations are more common among the healthy population. We propose a combined infrared method of rasterstereography and thermography to assess the back without harmful effects. This study aims to provide reference data on rasterstereography and thermography to evaluate the back of a healthy population and to further study the correlation between these two methods. This cross-sectional research involved 175 healthy individuals (85 males and 90 females) aged 22 to 35 years. There is a large Cohen’s d effect size in the cervical depth (males = 43.77 ± 10.96 mm vs. females = 34.29 ± 7.04 mm, d = 1.03), and in the lumbar lordosis angle (males = 37.69 ± 8.89° vs. females = 46.49 ± 8.25°, d = − 1.03). The back temperature was different for gender in the cervical area (males = 33.83 ± 0.63 °C vs. females = 34.26 ± 0.84 °C, d = − 0.58) and dorsal area (males = 33.13 ± 0.71 °C vs. females = 33.59 ± 0.97 °C, d = − 0.55). Furthermore, in the female group there was a moderate correlation of lumbar temperature with lumbar lordosis angle (r = − 0.50) and dorsal temperature with shoulders torsion (r = 0.43). Males showed a moderate correlation for vertebral surface rotation RMS with cervical (r = − 0.46), dorsal (r = − 0.60), and lumbar (r = − 0.50) areas and cervical temperature with shoulders obliquity (r = 0.58). These results highlight a possible correlation between rasterstereography and thermography, which may elucidate the underlying mechanics of spinal alterations and thermal muscle response. Our findings may represent reference data for other studies using noninvasive methods to assess postural alterations.
Purpose
To characterise hydration, cooling, body mass loss, and core (T core ) and skin (T sk ) temperatures during World Athletics Championships in hot-humid conditions.
Methods
Marathon and race-walk (20 km and 50 km) athletes (n=83, 36 women) completed a pre-race questionnaire. Pre-race and post-race body weight (n=74), T core (n=56) and T sk (n=49; thermography) were measured.
Results
Most athletes (93%) had a pre-planned drinking strategy (electrolytes (83%), carbohydrates (81%)) while ice slurry was less common (11%; p<0.001). More men than women relied on electrolytes and carbohydrates (91%–93% vs 67%–72%, p≤0.029). Drinking strategies were based on personal experience (91%) rather than external sources (p<0.001). Most athletes (80%) planned pre-cooling (ice vests (53%), cold towels (45%), neck collars (21%) and ice slurry (21%)) and/or mid-cooling (93%; head/face dousing (65%) and cold water ingestion (52%)). Menthol usage was negligible (1%–2%). Pre-race T core was lower in athletes using ice vests (37.5°C±0.4°C vs 37.8°C±0.3°C, p=0.024). T core (pre-race 37.7°C±0.3°C, post-race 39.6°C±0.6°C) was independent of event, ranking or performance (p≥0.225). Pre-race T sk was correlated with faster race completion (r=0.32, p=0.046) and was higher in non-finishers (did not finish (DNF); 33.8°C±0.9°C vs 32.6°C±1.4°C, p=0.017). Body mass loss was higher in men than women (−2.8±1.5% vs −1.3±1.6%, p<0.001), although not associated with performance.
Conclusion
Most athletes’ hydration strategies were pre-planned based on personal experience. Ice vests were the most adopted pre-cooling strategy and the only one minimising T core , suggesting that event organisers should be cognisant of logistics (ie, freezers). Dehydration was moderate and unrelated to performance. Pre-race T sk was related to performance and DNF, suggesting that T sk modulation should be incorporated into pre-race strategies.
Della Corte J, Pereira WLM, Corrêa EELS, Oliveira JGM, Lima BLP, Castro JBP, Lima VP. Influence of power and maximal strength training on thermal reaction and vertical jump performance in Brazilian basketball players: a preliminary study. Biomed Hum Kinet. 2020; 12(1): 91–100.
Study aim: To evaluate the effect of power and muscle strength training on skin temperature and the performance of the vertical jump with countermovement (CMJ).
Material and methods: The sample consisted of four male basketball athletes of the under-17 category (age: 15.75 ± 1.0 years). 48 hours after anthropometric evaluation and determination of the loads for 1 repetition maximum (1RM) in the leg extension exercise, the athletes were subjected, through crossover-type entrance, to power (PTP) and strength (STP) training protocols. The protocols consisted of three sets with loads of 60% and 90% of 1RM for PTP and STP, respectively. Thermographic images of the thighs were taken before and immediately after each training session.
Results: There were significant differences in results between the two training protocols, with increased total repetitions (t = 13.481; p < 0.05) and total training volume (t = 15.944; p < 0.05) in the PTP, and increase in the % of 1RM (t = 33.903; p < 0.05) and rating of perceived exertion (t = 6.755; p < 0.05) in the STP. The skin temperature before and after PTP and STP showed no significant differences. In the post-STP, the CMJ presented significant reductions in height (t = 3.318; p < 0.05), flight time (t = 3.620; p < 0.05), velocity (t = 3.502; p < 0.05), and force (t = 4.381; p < 0.05). There were no significant differences in pre-and post-STP CMJ.
Conclusions: Power and maximum strength training in the leg extension exercise performed until concentric failure appears to be a method that induces thermal stress on the skin. This training directly influenced the performance of the vertical jump after the stimulus.
Infrared thermography (IRT) is a non-invasive tool to measure the body surface radiation temperature (Tsr). IRT is an upcoming technology as a result of recent advancements in camera lenses, detector technique and data processing capabilities. The purpose of this review is to determine the potential and applicability of IRT in the context of dynamic measurements in exercise physiology. We searched PubMed and Google Scholar to identify appropriate articles, and conducted six case experiments with a high-resolution IRT camera (640 × 480 pixels) for complementary illustration. Ten articles for endurance exercise, 12 articles for incremental exercise testing and 11 articles for resistance exercise were identified. Specific Tsr changes were detected for different exercise types. Close to physical exertion or during prolonged exercise six recent studies described “tree-shaped” or “hyper-thermal” surface radiation pattern (Psr) without further specification. For the first time, we describe the Tsr and Psr dynamics and how these may relate to physiological adaptations during exercise and illustrate the differential responsiveness of Psr to resistance or endurance exercise. We discuss how bias related to individual factors, such as skin blood flow, or related to environmental factors could be resolved by innovative technological approaches. We specify why IRT seems to be increasingly capable of differentiating physiological traits relevant for exercise physiologists from various forms of environmental, technical and individual bias. For refined analysis, it will be necessary to develop and implement standardized and accurate pattern recognition technology capable of differentiating exercise modalities to support the evaluation of thermographic data by means of radiomics.
This study was focused on the thermal mapping of skin over the selected muscle zones in two groups of elite athletes fully engaged in completely other sports performing about an hour running effort at individual AT intensity. Two groups of elite male athletes, a group of cross-country skiers (CS; N = 6) and a group of elite endurance swimmers (SW; N = 4), were investigated. Thermal images of sportsmen’ body at front and from the rear were recorded before and about 1–2 min after exercise test using camera Flir Systems E60. Functional (heart rate, oxygen uptake, workload) as well as biochemical markers (activities of creatine kinase and lactate dehydrogenase, concentration of lactate and haemoglobin) were also assessed. The marked differentiation in skin temperature distribution in cross-country skiers and endurance swimmers subjected to the same endurance exercise on treadmill was observed. There was significant decrease in temperature in upper body temperature in CS group, while SW group revealed a significant increase in temperature of the lower limbs. The calculated total body skin temperature was also influenced by practicing training of elite athletes. Some significant correlations of physiological, biochemical and morphological parameters (% fat) with average temperature after exercise test were found for different muscle zones in swimmers and cross-country skiers. Statistical analysis showed that workload had the most impact on skin temperature changes, especially in swimmers. The results provide additional information on the muscle work in the different sport disciplines and may be helpful in efficiency evaluation of elite athletes.
Although moderate relationships (| r | ∼ 0.5) were reported between skin temperature and performance-related variables (e.g., kinetic), it remains unclear whether skin temperature asymmetry reflects muscle force imbalance in cycling. Therefore, the aim of this study was to assess whether a relationship exists between kinetic and thermal asymmetry during a fatiguing exercise. Ten elite cyclists were enrolled and tested on a maximal incremental cycling test. Peak crank torques of both legs were obtained at the initial and final workload. Likewise, bilateral skin temperatures were recorded before and after exercise. Asymmetric indexes were also calculated for kinetic (AI K ) and skin temperature (AI T ) outcomes. The bilateral peak crank torques showed a larger difference at the final compared to the initial workload ( p < 0.05) of the incremental exercise. Conversely, the bilateral skin temperature did not show any differences at both initial and final workload ( p > 0.05). Additionally, trivial relationships were reported between AI K and AI T (−0.3 < r < 0.2) at the initial and final workload. The obtained results showed that changes in bilateral kinetic values did not reflect concurrent changes in bilateral skin temperatures. This finding emphasizes the difficulty of associating the asymmetry of skin temperature with those of muscle effort in elite cyclists. Lastly, our study also provided further insights on thermal skin responses during exhaustive cycling exercise in very highly-trained athletes.
Background: Studies showed, that changes in muscular metabolic-associated heat production and blood circulation during and after muscular work affect skin temperature (T) but the results are inconsistent and the effect of exercise intensity is unclear. Objective: This study investigated the intensity-dependent reaction of T on resistance training. Methods: Ten male students participated. After acclimatization (15 min), the participants completed 3x10 repetitions of unilateral biceps curl with 30, 50 or 70% of their one-repetition-maximum (1RM) in a randomized order. Skin temperature of the loaded and unloaded biceps was measured at rest (T rest), immediately following set 1, 2 and 3 (T S1 ,T S2 ,T S3) and 30 minutes post exercise (T 1-T 30) with an infrared camera. Results: Two-way ANOVA detected a significant effect of the measuring time point on T (T rest to T 30) of the loaded arm for 30% (Eta²=0.85), 50% (Eta²=0.88) and 70% 1RM (Eta²=0.85) and of the unloaded arm only for 30% 1RM (Eta²=0.41) (p<0.05) but time effects were independent of the exercise intensity (p>0.05). The T values at the different measuring time points (T rest-T 30) did not differ between the intensities at any time point. The loaded arm showed a mean maximum T rise to T rest of 1.8°C and on average, maximum T was reached approximately 5 minutes after the third set. Conclusion: This study indicate a rise of T, which could be independent of the exercise intensity. Infrared thermography seems to be applicable to identify the primary used functional muscles in resistance training but this method seems not suitable to differentiate between exercise intensity from 30 to 70% 1RM.
This study aimed to identify the skin temperature (Tsk) behavior to understand the acute cross-effect after unilateral training of lower-limbs. Seventeen healthy young men (weight, 75.2± 5.5 kg; height, 1.8± 0.1 m; age, 22.5± 1.6 years) were divided into two groups: high-trained (n= 8) and low-trained (n= 9). All participants performed: (a) one-repetition maximum (1RM) testing protocol on the leg press, (b) a unilateral training protocol (4× 10 repetitions at 70% of 1RM for leg press and 4× 10 repetitions at 50% of 1RM for knee extension). Pre-and posttraining thermal images were recorded. The main results showed that independent of the limb (exercised vs. nonexercised), differences between low-and high-trained were observed for all regions of interest (ROI) except for the anterior knee: posttraining, 30-min and 60-min posttraining in nonexercised limb. The increase of contralateral Tsk was more than 50% on the ROIs corresponding to the exercises muscles 30-min post-training in low-trained but was not so high in high-trained (P< 0.05). Low-trained subjects incremented more the Tsk than high-trained in both legs after exercise. In conclusion, we observed an acute contra-lateral Tsk effect to unilateral training on the Tsk of the nonexercised limb, reliant on the training level of the subject.
In order to achieve higher efficiency of training and thus better athletic performance, new research and diagnostic methods are constantly being developed, particularly those that are non-invasive. One such a method is thermography, suitable for quantitative and therefore objective evaluation of variables, such as changes in the temperature of the skin covering working muscles. The aim of this study was to use a thermal imaging infrared camera to evaluate temperature changes of symmetric body surfaces over symmetrically working muscles of male scullers after exercising on a two-oared rowing ergometer and compare these to asymmetrically working muscles of handball players after an endurance training session containing elements of an actual game. In the scullers, the mean temperature of body surfaces was always lower post than pre exercise, with no significant differences in an average temperature drop between the opposite sides, indicating that the work of the muscles involved in the physical exertion on the rowing ergometer was symmetrical. In contrast, in the handball players, skin temperatures in symmetric areas over the asymmetrically working muscles showed statistically significant differences between sides, which was associated with the functional asymmetry of training. This study indicates that thermal imaging may be useful for coaches in the evaluation of technical preparations in sports in which equal involvement of symmetric muscles is a condition of success, e.g. in scullers.
Body temperature is one of the most commonly used indicators of health status in humans. Infrared thermography (IRT) is a safe, non-invasive and low-cost technique that allows for the rapid and non-invasive recording of radiating energy that is released from the body. IRT measures this radiation, directly related to Skin Temperature (Tsk) and has been widely used since the early 1960s in different areas. Recent technical advances in infrared cameras have made new human applications of IRT (beyond diagnostic techniques) possible. This review focuses on the lack of comprehensive information about the factors influencing the use of IRT in humans, and proposes a comprehensive classification in three primary groups: environmental, individual and technical factors. We aim: to propose a common framework for further investigations; to reinforce the accuracy of human IRT; to summarise and discuss the results from the studies carried out on each factor and to identify areas requiring further research to determine their effects on human IRT.
Changes in body temperature and in the blood lactate concentration are typical symptoms of an organism's reaction to effort. The aim of this work was to search for a relation between the temperature of the lower extremities and the blood lactate concentration. Sixteen non-training male subjects took part in the test (average age: 22.3±1.6 years). They performed maximum-height jumps from a fully knee-bent position for one minute. Their body temperature was measured by thermographic imaging and blood lactate concentration was determined at the beginning and throughout a thirty-minute recovery. An analysis of isotherms showed a strong dependence between the temperature of the front surface (FS) and back surface (BS) of the lower extremities (r=.83, p<.05). Immediately after exercise the temperature of the lower limbs decreased on average by about 1.44°C (p<.001) and then during the recovery period rose almost to the pre-exercise value. There was a significant negative correlation (r=-.29, p<.05) between the temperature of lower limbs and the blood lactate concentration, both for FS (r=-.22, p<.05) and BS (r=-.23, p<.05). The results show that a maximum anaerobic effort is accompanied by a substantial drop of the temperature on surface of engaged muscles and the degree of the drop is proportional to the blood lactate concentration.
What mechanism has greater
influence on skin temperature during, and after,
the muscular work: peripheral vasoconstriction or
muscle heat dissipation? And yet, at what time
each one preponderates? In this sense, the present
study aimed to analyze, in time domain, the skin
temperature variations during muscular exercise.
This study can be characterized as a short-term
longitudinal study. The study was conducted with
two male able-bodied volunteers, with 22 and 23
yrs, both physically active. The exercise
proposed was the unilateral biceps curl, with
dominant arm. The data from the contralateral
arm was used as control. A Visual Analogue
Scale (VAS) for pain was used to monitor the
muscular pain perception during 48 hours after
the exercise. The results show the temperature
decreases during the first minute (between the
start and the end of the first set of exercise). The
end of 3rd set can be observed an average
increase in the temperature of study arm of
approximately 8.4% compared to the initial
temperature and an average difference of
approximately 6.6% compared to the control arm.
In conclusion, the temperature of the skin over
the main muscle of high-intensity exercise
(performing until fatigue) decreases at the initial
stage and then increases continuously until
muscle fatigue. The exercise induced muscle
damage (EIMD) can be predicted by assessment
of muscle skin temperature 24 hours after
exercise.
Introduction: Since muscle injuries trigger inflammatory processes and inflammation generates heat due to increased local metabolism, hence the level of inflammation can be measured by the temperature gradient. Objective: To assess the feasibility of application of thermography in the diagnosis of injuries caused by physical training. Methods: The study was conducted with adolescent athletes of the Paraná Club, Curitiba, Brazil, who were divided into two groups, namely control and experimental. The control group attended a training session of low intensity and the experimental group a high intensity one. First, a thermographic image of the quadriceps of each athlete was acquired before the training session. After the training session, a blood sample was collected to check the level of serum lactate of each athlete. Subsequently, 24 hours after training, an extra blood sample was performed to check the level of serum CK of each athlete. Another individual thermographic image of the quadriceps was acquired at that stage. Results: The correlation between the lactate and CK was positive and statistically significant rho value = 0.661 (p = 0.038). There was no statistically significant correlation between CK values 24 h post-training and the change in temperature (24 h post-training - pre-training) in the muscles evaluated for the control group. There was a statistically significant difference in temperature (24 h post-training - pre-training) (p<0.05) for the three muscles studied only in the experimental group. Conclusion: The results of this study suggest the possibility of use of thermographic images, together with creatine kinase, in order to determine the intensity and location of post-training muscle damage, since the previously mentioned biochemical marker cannot determine the anatomic location of the muscle injury.
Heat dissipation during sport exercise is an important physiological mechanism that may influence athletic performance. Our aim was to test the hypothesis that differences exist in the dynamics of exercise-associated skin temperature changes between trained and untrained subjects. We investigated thermoregulation of a local muscle area (muscle-tendon unit) involved in a localized steady-load exercise (standing heels raise) using infrared thermography. Seven trained female subjects and seven untrained female controls were studied. Each subject performed standing heels raise exercise for 2 min. Thermal images were recorded prior to exercise (1 min), during exercise (2 min), and after exercise (7 min). The analysis of thermal images provided the skin temperature time course, which was characterized by a set of descriptive parameters. Two-way ANOVA for repeated measures detected a significant interaction (p = 0.03) between group and time, thus indicating that athletic subjects increased their skin temperature differently with respect to untrained subjects. This was confirmed by comparing the parameters describing the speed of rise of skin temperature. It was found that trained subjects responded to exercise more quickly than untrained controls (p < 0.05). In conclusion, physical training improves the ability to rapidly elevate skin temperature in response to a localized exercise in female subjects.
Infrared thermal imaging is being increasingly utilised in the study of neurological and musculoskeletal disorders. In these conditions data on the symmetry (or the lack of it) of skin temperature provides valuable information to clinicians. A major study on thermal symmetry, however, was made in 1988 but there is an absence of studies with the current generation of higher resolution cameras. No study to date has compared total body views with close-up regional views in both anterior and dorsal views.
In this study skin temperature measurements have been carried out using thermograms of 39 healthy male subjects. Measurements were obtained from an infrared camera using the CTHERM application developed at the authors’ research unit. CTHERM is capable of calculating statistical data such as temperature averages and standard deviation values in corresponding areas of interest on both sides of the body. Results show that in healthy subjects the highest temperature symmetry difference was at most 0.4ºC±0.3ºC in total body views and 0.4ºC±0.15ºC in regional views. Total body views and regional views produced comparable results although less variation was achieved in regional views. Using a high-resolution camera the study achieved better results on thermal symmetry in normal subjects than previously reported. Symmetry assumptions can therefore be used with higher confidence when assessing abnormalities in specific pathologic states.
In this paper we used high-resolution thermal imaging to visualize the human whole body anterior cutaneous temperature (T
c) variations in well-trained runners during graded exercise. Fifteen male volunteers underwent a graded treadmill test until reaching their individual maximal heart rate. Total body T
c decreased as the subjects started the exercise. Thighs and forearms exhibited the earliest response. A further T
c diminution occurred with the progress of the exercise. At the exercise interruption, T
c values were in average 3–5 °C lower than at baseline. T
c increased during recovery from exercise. Forearms and thighs exhibited the earliest increase, followed by total body T
c increase. Thermal imaging documented the presence of hyperthermal spots (occasionally tree-shaped) due to the presence of muscle perforator vessels during baseline and recovery, but not during exercise. The results we report indicate that thermal infrared imaging permits the quantitative evaluation of specific cutaneous whole body thermal adaptations which occur during and after graded physical activity. Thus providing the basis for evaluating local and systemic cutaneous blood flow adaptation as a function of specific type, intensity and duration of exercise, and helping to determine the ideal conditions (in terms of environment and apparel) in which physical activities should be conducted in order to favor thermal regulatory processes.
Medical infrared thermography (MIT) is used for analyzing physiological functions related to skin temperature. Technological advances have made MIT a reliable medical measurement tool. This paper provides an overview of MIT's technical requirements and usefulness in sports medicine, with a special focus on overuse and traumatic knee injuries. Case studies are used to illustrate the clinical applicability and limitations of MIT. It is concluded that MIT is a non-invasive, non-radiating, low cost detection tool which should be applied for pre-scanning athletes in sports medicine.
One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for 8 standard statistical tests: (1) the difference between independent means, (2) the significance of a product-moment correlation, (3) the difference between independent rs, (4) the sign test, (5) the difference between independent proportions, (6) chi-square tests for goodness of fit and contingency tables, (7) 1-way analysis of variance (ANOVA), and (8) the significance of a multiple or multiple partial correlation.
This study determined whether cutaneous blood flow during exercise is different in endurance-trained (Tr) compared with untrained (Untr) subjects. Ten Tr and ten Untr men (62.4 +/- 1.7 and 44.2 +/- 1.8 ml. kg(-1). min(-1), respectively; P < 0.05) underwent three 20-min cycling-exercise bouts at 50, 70, and 90% peak oxygen uptake in this order, with 30 min rest in between. The environmental conditions were neutral ( approximately 23-24 degrees C, 50% relative humidity, front and back fans at 2.5 m/s). Because of technical difficulties, only seven Tr and seven Untr subjects completed all forearm blood flow and laser-Doppler cutaneous blood flow (CBF) measurements. Albeit similar at rest, at the end of all three exercise bouts, forearm blood flow was approximately 40% higher in Tr compared with Untr subjects (50%: 4.64 +/- 0.50 vs. 3. 17 +/- 0.20, 70%: 6.17 +/- 0.61 vs. 4.41 +/- 0.37, 90%: 6.77 +/- 0. 62 vs. 5.01 +/- 0.37 ml. 100 ml(-1). min(-1), respectively; n = 7; all P < 0.05). CBF was also higher in Tr compared with Untr subjects at all relative intensities (n = 7; all P < 0.05). However, esophageal temperature was not different in Tr compared with Untr subjects at the end of any of the aforementioned exercise bouts (50%: 37.8 +/- 0.1 vs. 37.9 +/- 0.1 degrees C, 70%: 38.1 +/- 0.1 vs. 38.1 +/- 0.1 degrees C, and 90%: 38.8 +/- 0.1 vs. 38.6 +/- 0.1 degrees C, respectively). We conclude that a higher CBF may allow Tr subjects to achieve an esophageal temperature similar to that of Untr, despite their higher metabolic rates and thus higher heat production rates, during exercise at 50-90% peak oxygen uptake.
Unlabelled:
The occurrence of post-exercise hypotension after resistance exercise is controversial, and its mechanisms are unknown. To evaluate the effect of different resistance exercise intensities on post-exercise blood pressure (BP), and hemodynamic and autonomic mechanisms, 17 normotensives underwent three experimental sessions: control (C-40 min of rest), low- (E40%-40% of 1 repetition maximum, RM), and high-intensity (E80%-80% of 1 RM) resistance exercises. Before and after interventions, BP, heart rate (HR), and cardiac output (CO) were measured. Autonomic regulation was evaluated by normalized low- (LF(R-R)nu) and high-frequency (HF(R-R)nu) components of the R-R variability. In comparison with pre-exercise, systolic BP decreased similarly in the E40% and E80% (-6 +/- 1 and -8 +/- 1 mmHg, P < 0.05). Diastolic BP decreased in the E40%, increased in the C, and did not change in the E80%. CO decreased similarly in all the sessions (-0.4 +/- 0.2 l/min, P < 0.05), while systemic vascular resistance (SVR) increased in the C, did not change in the E40%, and increased in the E80%. Stroke volume decreased, while HR increased after both exercises, and these changes were greater in the E80% (-11 +/- 2 vs. -17 +/- 2 ml/beat, and +17 +/- 2 vs. +21 +/- 2 bpm, P < 0.05). LF(R-R)nu increased, while ln HF(R-R)nu decreased in both exercise sessions.
In conclusion:
Low- and high-intensity resistance exercises cause systolic post-exercise hypotension; however, only low-intensity exercise decreases diastolic BP. BP fall is due to CO decrease that is not compensated by SVR increase. BP fall is accompanied by HR increase due to an increase in sympathetic modulation to the heart.
This study aimed at evaluating the thermographic changes associated with localized exercise in young and elderly subjects. An exercise protocol using 1 kg load was applied during 3 min to the knee flexors of 14 elderly (67 +/- 5 years) and 15 young (23 +/- 2 years) healthy subjects. The posterior thigh's skin temperature of the exercised limb and contralateral limb were measured by infrared thermography on pre-exercise, immediately post-exercise, and during the 10-min period post-exercise. Difference (p < 0.01) between elderly and young subjects was observed on pre-exercise temperature. Although differences were not observed between pre-exercise and immediately post-exercise temperature in the exercised limb, thermographic profile displayed heat concentration in exercised areas for both groups. Temperature reduction was only observed for the young group on the 10-min post-exercise (p < 0.05) in the exercised limb (30.7 +/- 1.7 to 30.3 +/- 1.5 degrees C). In contrast, there was a temperature reduction post-exercise (p < 0.01) in the contralateral limb for both groups. These results present new evidences that elderly and young subjects display similar capacity of heat production; however, the elderly subjects presented a lower resting temperature and slower heat dissipation. This work contributes to improve the understanding about temperature changes in elderly subjects and may present implications to the sports and rehabilitation programs.
Introduction
Exercise induces modifications in thermal homeostasis. The type of exercise may have a specific impact on skin temperature (Tsk).
Objective
To analyze and compare the behavior of Tsk in a resistance training between men and women and monitor the thermal recovery response.
Material and Methods
Sixteen male and female adults (24.56 ± 3.22 years old) underwent a resistance circuit training session. They performed 3 sets of 12 repetitions with 70–80% 1 RM for lat pulldown, leg press, and biceps arm curl exercises. Thermograms were taken in anterior and posterior body view at rest, 20 min, and 24 h after training. Tsk was measured in the body regions of interest corresponding to the brachial biceps, quadriceps, and upper back. ANOVA with Tukey's post hoc test was used to analyze Tsk changes among moments, and independent samples t-test was used to compare Tsk between males and females.
Results
At rest, women showed Tsk significantly lower than men. There was no significant Tsk change 20 min after exercise. However, Tsk increased 24 h after exercise in the upper back for men compared with baseline and in quadriceps for women compared with baseline and 20 min after exercise (p < 0.05).
Conclusion
The Tsk of women at rest is lower than that of men. A resistance circuit training session does not significantly change Tsk 20 min after exercise, but it increases Tsk 24 h after training in the upper back for men and quadriceps for women.
Objectives
To determine normal temperatures over the Patella tendon over eleven weeks.
Design
A prospective cohort study with eleven weeks of observation.
Setting
University's Human Biomechanics and Physiology Laboratory.
Participants
Male or female collegiate runners running at least 25 miles per week who did not report pain in the region of the Patella tendon over 11 weeks of data collection.
Main outcome measures
Thermal images taken at the same time and day of the week, were used to measure the temperature of the skin over the Patella tendon.
Results
Eighteen athletes were eligible for analysis. The mean temperature of the Patella tendon was 30.13 °C (SD = 1.51 °C). Patella tendon temperature changes over time were insignificant (right p = 0.66, left p = 0.90) with ICC right = 0.92, left = 0.94. Mean temperature difference side to side was 0.14 °C (SD = 0.60 °C). Mixed-model Linear regression for mean temperature differences found the effect of (i) time (t = 0.39, p = 0.70, df = 361) and (ii) side (t = −0.89, p = 0.38, df = 361) to be insignificant.
Conclusions
This is the first report of normal thermal profiles of collegiate runners over an extended period. Temperature variation above 1.20 °C may represent an abnormal asymmetry in the running population. Variations in Patella tendon temperatures left to right, and over time were not significant.
There are controversial results in the literature concerning the concept that cumulative training load could affect basal skin temperature in the days following training sessions. The objective was to measure skin temperature in triathletes during a training camp with cumulative training load. Ten male recreational triathletes involved in a training camp underwent measurements of perception of pain and fatigue (visual analogue scale), skin temperature (infrared thermography), and jump performance (counter movement jump test) before, one day, and
two days after the beginning of the training camp. All measurements were performed before the breakfast. Jump height did not differ between the days (p > 0.05). Fatigue perception increased after the first and second day of training for most of the body regions (p < 0.05). Pain perception increased after two days of training (p < 0.05). Mean and maximum skin temperature increased after the second day of training for most of the body regions (p < 0.05). Skin temperature in some body regions was directly related with muscle mass, weekly training volume, and inverse related with fatigue perception (p < 0.05 and R2 > 0.4). Possible explanations of these results in comparison with previous studies may include the influence of control of the intrinsic and
extrinsic factors related to the skin temperature assessment (for instance, the time of the day, lack of muscle soreness, daily activity control). These preliminary results have important implication on the use of skin basal temperature data to monitor exercise recovery, which claims for further research.
The importance of using infrared thermography (IRT) to assess skin temperature (tsk) is increasing in clinical settings. Recently, its use has been increasing in sports and exercise medicine; however, no consensus guideline exists to address the methods for collecting data in such situations. The aim of this study was to develop a checklist for the collection of tsk using IRT in sports and exercise medicine. We carried out a Delphi study to set a checklist based on consensus agreement from leading experts in the field. Panelists (n = 24) representing the areas of sport science (n=8; 33%), physiology (n=7; 29%), physiotherapy (n=3; 13%) and medicine (n=6; 25%), from 13 different countries completed the Delphi process. An initial list of 16 points was proposed which was rated and commented on by panelists in three rounds of anonymous surveys following a standard Delphi procedure. The panel reached consensus on 15 items which encompassed the participants’ demographic information, camera/room or environment setup and recording/analysis of tsk using IRT. The results of the Delphi produced the checklist entitled “Thermographic Imaging in Sports and Exercise Medicine (TISEM)” which is a proposal to standardize the collection and analysis of tsk data using IRT. It is intended that the TISEM can also be applied to evaluate bias in thermographic studies and to guide practitioners in the use of this technique.
Resistance training is recommended by national health organizations for incorporation into a comprehensive fitness program that includes aerobic and flexibility exercise. Its potential benefits on health and performance are numerous; it has been shown to reduce body fat, increase basal metabolic rate, decrease blood pressure and the cardiovascular demands to exercise, improve blood lipid profiles, glucose tolerance, and insulin sensitivity, increase muscle and connective tissue cross-sectional area, improve functional capacity, and relieve low back pain. Many improvements in physical function and athletic performance are associated with the increases in muscle strength, power, endurance, and hypertrophy observed during resistance training. The key element to effective resistance training is supervision by a qualified professional and the proper prescription of the program variables. Proper program design, ie, that which uses progressive overload, variation, and specificity, is essential to maximize the benefits associated with resistance training.
In this chapter, we will describe how infrared thermography (IRT) can help us to prevent and monitor injuries, always based on the use of standardised protocols. We will explain some of the main physiological aspects and will enumerate the main applications, with examples gathered from our research and professional experience with top sport athletes and teams. To summarize, IRT can help us to reduce injury incidence and to increase the performance in a non-invasive, fast and objective way.
Low intensity resistance training with slow movement and tonic force generation has been shown to create blood flow restriction within muscles that may affect thermoregulation through the skin. We aimed to investigate the influence of two speeds of exercise execution on skin temperature dynamics using infrared thermography. Thirteen active males performed randomly two sessions of squat exercise (normal speed, 1 s eccentric/1 s concentric phase, 1 s; slow speed, 5 s eccentric/5 s concentric phase, 5 s), using ~50% of 1 maximal repetition. Thermal images of ST above muscles quadriceps were recorded at a rate of 0.05 Hz before the exercise (to determine basal ST) and for 480 s following the initiation of the exercise (to determine the nonsteady-state time course of ST). Results showed that ST changed more slowly during the 5 s the 1 s exercise (p=0.002), whereas the delta (with respect to basal) excursions were similar for the two exercises (p>0.05). In summary, our data provided a detailed nonsteady-state portrait of ST changes following squat exercises executed at two different speeds. These results lay the basis for further investigations entailing the joint use of infrared thermography and Doppler flowmetry to study the events taking place both at the skin and the muscle level during exercises executed at slow speed.
It was known that the thermal response varies according to some variables. Until now, there are no studies that have investigated the relationship of skin temperature and heart rate during and after the workout, either the thermal behavior during postural changes. Objective: the aim of this study was to evaluate the behavior of skin temperature and heart rate, during exercise and up to an hour of recovery (with postural change), performed in two different intensities sessions (70% and 85% of 10 repetitions maximum) and observe the correlation between them. Method: This was a short longitudinal study, carried out with women aged from 18 to 30 years. A sample of 31 untrained women, aged 18 and 30 was used. The volunteers were randomized into two groups: Biceps Group (BG), with 15 women, and Quadriceps Group (QG) with 16 women. Results: During and after completion of the exercise session, there was a significant reduction in skin temperature on the active muscles in both groups (BG and QG), with similar thermal responses for the two intensities studied (70% and 85%) to the minute 15 (which marks the end of the recovery in the standing position). From minute 15 to minute 20-60, the skin temperature increases abruptly and significantly, returning to levels close to those observed before exercise. Conclusion: There were no statistical differences in thermal response to exercises in 70% or 85% of 10RM. There is a negative correlation between heart rate and skin temperature when untrained women perform anaerobic exercise. It was observed that after a change of posture (from a standing position to a sitting posture) skin temperature increased abruptly and significantly.
William Herschel first recognized heat emitted in the infrared (IR) wave spectrum in the 1800s. Medical infrared, popularly known as IR-thermography has utilized this heat signature since the 1960s to measure and map skin temperatures. Our understanding of the regulation of skin blood flow, heat transfers through the tissue layers, and skin temperatures has radically changed during these past 40 years, allowing us to better interpret and evaluate these thermographic measurements. During this same period of time, improved camera sensitivity coupled with advances in focal plan array technology and new developments in computerized systems with assisted image analysis have improved the quality of the noncontact, noninvasive thermal map or thermogram [1-3]. In a recent electronic literature search in Medline using the keywords “thermography” and “thermogram” more than 5000 hits were found [4]. In 2003 alone, there were 494 medical references, 188 basic science, 148 applied science (14 combined with Laser Doppler and Bronz: "2122_c021" - 2006/2/16 - 20:19 - page 2 - #2 28 combined with ultrasound research), and 47 in biology including veterinary medicine [5]. Further databases and references for medical thermography since 1987 are available [6].
SUMMARY In order to stimulate further adaptation toward specific training goals, progressive resistance training (RT) protocols are necessary. The optimal characteristics of strength-specific programs include the use of concentric (CON), eccentric (ECC), and isometric muscle actions and the performance of bilateral and unilateral single- and multiple-joint exercises. In addition, it is recommended that strength programs sequence exercises to optimize the preservation of exercise intensity (large before small muscle group exercises, multiple-joint exercises before single-joint exercises, and higher-intensity before lower-intensity exercises). For novice (untrained individuals with no RT experience or who have not trained for several years) training, it is recommended that loads correspond to a repetition range of an 8-12 repetition maximum (RM). For intermediate (individuals with approximately 6 months of consistent RT experience) to advanced (individuals with years of RT experience) training, it is recommended that individuals use a wider loading range from 1 to 12 RM in a periodized fashion with eventual emphasis on heavy loading (1-6 RM) using 3- to 5-min rest periods between sets performed at a moderate contraction velocity (1-2 s CON; 1-2 s ECC). When training at a specific RM load, it is recommended that 2-10% increase in load be applied when the individual can perform the current workload for one to two repetitions over the desired number. The recommendation for training frequency is 2-3 dIwkj1 for novice training, 3-4 dIwkj1 for intermediate training, and 4-5 dIwkj1 for advanced training. Similar program designs are recom- mended for hypertrophy training with respect to exercise selection and frequency. For loading, it is recommended that loads corresponding to 1-12 RM be used in periodized fashion with emphasis on the 6-12 RM zone using 1- to 2-min rest periods between sets at a moderate velocity. Higher volume, multiple-set programs are recommended for maximizing hypertrophy. Progression in power training entails two general loading strategies: 1) strength training and 2) use of light loads (0-60% of 1 RM for lower body exercises; 30-60% of 1 RM for upper body exercises) performed at a fast contraction velocity with 3-5 min of rest between sets for multiple sets per exercise (three to five sets). It is also recommended that emphasis be placed on multiple-joint exercises especially those involving the total body. For local muscular endurance training, it is recommended that light to moderate loads (40-60% of 1 RM) be performed for high repetitions (915) using short rest periods (G90 s). In the interpretation of this position stand as with prior ones, recommendations should be applied in context and should be contingent upon an individual's target goals, physical capacity, and training
Extracellular signal-regulated kinase (ERK) 1/2 signaling has been shown to be increased after heavy resistance exercise and suggested to play a role in the hypertrophic adaptations that are known to occur with training. However, the role that ERK1/2 may play in response to lower intensities of resistance exercise is unknown. Therefore, the purpose of this study was to determine the effects of resistance exercise intensity on ERK1/2 activity in human skeletal muscle. Twelve recreationally active men completed separate bouts of single-legged resistance exercise with 8-10 repetitions (reps) at 80-85% 1 repetition maximum (1RM) (85%) and 18-20 reps at 60-65% 1RM (65%) in a randomized crossover fashion. For both resistance exercise sessions, vastus lateralis biopsies and blood draws were taken immediately before exercise (PRE) and at 30 minutes (30MPST), 2 hours (2HRPST), and 6 hours (6HRPST) post exercise, with an additional blood draw occurring immediately after exercise (POST). The phosphorylated levels of pIGF-1R, pMEK1, pERK1/2, and activated Elk-1 were assessed by phosphoELISA, and serum insulin-like growth factor 1 (IGF-1) was assessed via enzyme-linked immunosorbent assay. Statistical analyses used a 2 × 4 (muscle responses) and 2 × 5 (serum responses) multivariate analysis of variance on delta values from baseline (p < 0.05). Both exercise intensities significantly increased the activity of insulin-like growth factor 1 receptor (IGF-1R), mitogen-activated protein kinase 1, ERK1/2, and Elk-1, with peak activity occurring at 2HRPST (p < 0.001). However, 65% resulted in a preferential increase in IGF-1R and Elk-1 activation when compared with 85% (p < 0.05). No differences were observed for serum IGF-1 levels regardless of intensity and time. These findings demonstrate that resistance exercise upregulates ERK1/2 signaling in a manner that does not appear to be preferentially dependent on exercise intensity.
Delayed onset muscle soreness (DOMS), also known as exercise induced muscle damage (EIMD), is commonly experienced in individuals who have been physically inactive for prolonged periods of time, and begin with an unexpected bout of exercise, but can also occur in athletes who exercise beyond their normal limits of training. The symptoms associated with this painful phenomenon can range from slight muscle tenderness, to severe debilitating pain. The intensity of these symptoms and the related discomfort increases within the first 24 hours following the termination of the exercise, and peaks between 24 to 72 hours post exercise. For this reason, DOMS is one of the most common recurrent forms of sports injury that can affect an individual's performance, and become intimidating for many. For the last 3 decades, the DOMS phenomenon has gained a considerable amount of interest amongst researchers and specialists in exercise physiology, sports, and rehabilitation fields. There has been a variety of published studies investigating this painful occurrence in regards to its underlying mechanisms, treatment interventions, and preventive strategies. However, it is evident from the literature that DOMS is not an easy pathology to quantify, as there is a wide amount of variability between the measurement tools and methods used to quantify this condition. It is obvious that no agreement has been made on one best evaluation measure for DOMS, which makes it difficult to verify whether a specific intervention really helps in decreasing the symptoms associated with this type of soreness or not. Thus, DOMS can be seen as somewhat ambiguous, because many studies depend on measuring soreness using a visual analog scale (VAS), which is a subjective rather than an objective measure. Even though needle biopsies of the muscle, and blood levels of myofibre proteins might be considered a gold standard to some, large variations in some of these blood proteins have been documented, in addition to the high risks sometimes associated with invasive techniques. Therefore, in the current investigation, we tested a thermal infra-red (IR) imaging technique of the skin above the exercised muscle to detect the associated muscle soreness. Infra-red thermography has been used, and found to be successful in detecting different types of diseases and infections since the 1950's. But surprisingly, near to nothing has been done on DOMS and changes in skin temperature. The main purpose of this investigation was to examine changes in DOMS using this safe and non-invasive technique.
The magnitude and duration of the elevation in resting energy expenditure after vigorous exercise have not been measured in a metabolic chamber. This study investigated the effects of inserting a 45-min vigorous cycling bout into the daily schedule versus a controlled resting day on 24-h energy expenditure in a metabolic chamber.
Ten male subjects (age = 22-33 yr) completed two separate 24-h chamber visits (one rest and one exercise day), and energy balance was maintained for each visit condition. On the exercise day, subjects completed 45 min of cycling at 57% Wmax (mean ± SD = 72.8% ± 5.8% VO(2)max) starting at 11:00 a.m. Activities of daily living were tightly controlled to ensure uniformity on both rest and exercise days. The area under the energy expenditure curve for exercise and rest days was calculated using the trapezoid rule in the EXPAND procedure in the SAS and then contrasted.
The 45-min exercise bout resulted in a net energy expenditure of 519 ± 60.9 kcal (P < 0.001). For 14 h after exercise, energy expenditure was increased 190 ± 71.4 kcal compared with the rest day (P < 0.001).
In young male subjects, vigorous exercise for 45 min resulted in a significant elevation in postexercise energy expenditure that persisted for 14 h. The 190 kcal expended after exercise above resting levels represented an additional 37% to the net energy expended during the 45-min cycling bout. The magnitude and duration of increased energy expenditure after a 45-min bout of vigorous exercise may have implications for weight loss and management.
Teamgym is a new and emerging closed-skill sport, which includes tumbling, trampette, and floor programs performed by teams ranging from 6 to 12 athletes. The purpose of this study was to verify the concurrent validity of the session-rating of perceived exertion ([RPE] session-RPE) to quantifying the internal training load (ITL) of tumbling, trampette, and floor training sessions using Edwards' summated heart rate (HR)-zone method as a criterion measure. Session-RPE was obtained with 2 different instruments (i.e., CR-10 Borg's scale and visual analog scale) multiplied by the training duration (minutes). Ten female teamgym athletes (age = 21.7 ± 1.2 years; height = 164.9 ± 6.6 cm; and body mass = 54.6 ± 5.4 kg) participated in this study. High and significant correlations (r range: 0.77-0.85; R range: 0.59-0.85; p < 0.01) were found between Edwards' HR and the session-RPE methods and between the 2 session-RPE instruments (r range: 0.92-0.97; R2 range: 0.85-0.94; p < 0.01). The significant (p < 0.05) differences emerged between training sessions indicate that session-RPE discriminates ITL in relation to various technical skills. Hence, session-RPE can be a useful and inexpensive tool to quantify ITL in teamgym, and coaches could use this instrument to monitor their periodization plan as experienced by the athletes.
This study investigated the effects of hot (H) and room temperature (RT) recovery environments on glycogen resynthesis. Nine male participants completed two trials, cycling for 1 h in a temperature-controlled chamber (32.6 degrees C), followed by 4 h of recovery at 32.6 degrees C (H) or 22.2 degrees C (RT). Rectal temperature was continuously recorded. A carbohydrate beverage (1.8 g/kg bodyweight) was supplied at 0 and 2 h post-exercise. Muscle biopsies were taken immediately, 2 h, and 4 h post-exercise for glycogen analysis. Blood samples were taken at 30, 60, 120, 150, 180, and 240 min into recovery for glucose and insulin analysis. Expired gas was collected at 105 min and 225 min into recovery to calculate whole body carbohydrate oxidation. Average core temperature, whole body carbohydrate oxidation, and serum glucose at 120, 150, 180 and 240 min was higher in H compared to RT (p<0.05). Muscle glycogen was higher in RT vs. H at 4 h (105+/-28 vs. 88+/-24 mmolxkg (-1) wet weight, respectively; p<0.05), but no different at 0 and 2 h. There was no difference in serum insulin. These data indicate the importance of minimizing the exposure to heat after exercise to improve recovery, specifically to improve glycogen resynthesis.
Human skin blood flow responses to body heating and cooling are essential to the normal processes of physiological thermoregulation. Large increases in skin blood flow provide the necessary augmentation of convective heat loss during environmental heat exposure and/or exercise, just as reflex cutaneous vasoconstriction is key to preventing excessive heat dissipation during cold exposure. In humans, reflex sympathetic innervation of the cutaneous circulation has two branches: a sympathetic noradrenergic vasoconstrictor system, and a non-noradrenergic active vasodilator system. Noradrenergic vasoconstrictor nerves are tonically active in normothermic environments and increase their activity during cold exposure, releasing both norepinephrine and cotransmitters (including neuropeptide Y) to decrease skin blood flow. The active vasodilator system in human skin does not exhibit resting tone and is only activated during increases in body temperature, such as those brought about by heat exposure or exercise. Active cutaneous vasodilation occurs via cholinergic nerve cotransmission and has been shown to include potential roles for nitric oxide, vasoactive intestinal peptide, prostaglandins, and substance P (and/or neurokinin-1 receptors). It has proven both interesting and challenging that no one substance has been identified as the sole mediator of active cutaneous vasodilation. The processes of reflex cutaneous vasodilation and vasoconstriction are both modified by acute factors, such as exercise and hydration, and more long-term factors, such as aging, reproductive hormones, and disease. This review will highlight some of the recent findings in these areas, as well as interesting areas of ongoing and future work.
This brief review examines five problems concerning arterial blood pressure regulation during exercise. These are: 1. A history and summary of evidence that baroreflexes are, or are not, active during exercise. 2. What might be other "regulators" of blood pressure during exercise? The characteristics of a blood pressure-raising reflex from ischemic and active skeletal muscle (muscle chemoreflex) is reviewed along with a putative role for centrally generated motor command signals (central command). 3. How blood pressure is maintained during exercise. The importance of regional vasoconstriction, particularly in active skeletal muscle, is reviewed. 4. How well matched are cardiac output and total vascular conductance? Does demand for muscle blood flow outstrip cardiac pumping capacity? 5. Reflex control of blood pressure by both baroreflexes and muscle chemoreflexes. The importance of baroreflexes and evidence for resetting is reviewed. A new hypothesis is stated.
Using skin temperature and muscle thickness to assess muscle response to strength training
- E B Neves
- T R Moreira
- R Lemos
- J Vilaça-Alves
- C Rosa
- V M Reis
- EB Neves
Neves EB, Moreira TR, Lemos R, Vilaça-Alves J, Rosa C, Reis
VM. Using skin temperature and muscle thickness to assess muscle response to strength training. Revista Brasileira de Medicina
do Esporte. 2015;21(5):350-4.
Essentials of strength training and conditioning. Champaign: Human Kinetics
- T R Baechle
- R W Earle
- TR Baechle
Baechle TR, Earle RW. Essentials of strength training and conditioning. Champaign: Human Kinetics; 2008.