المؤلفون: Malta, Elvis Souza, Lopes, Vithor Hugo Fialho, Esco, Michael R., Zagatto, Alessandro Moura

المصدر: European Journal of Applied Physiology; Sep2023, Vol. 123 Issue 9, p1939-1948, 10p

مصطلحات موضوعية: HEART beat, CREATINE kinase, LACTATE dehydrogenase, BLOOD lactate

مستخلص: Purpose: The study aimed to investigate the effect of repeated cold-water immersion (CWI) after high-intensity interval exercise sessions on cardiac-autonomic modulation, neuromuscular performance, muscle damage markers, and session internal load. Methods: Twenty-one participants underwent five sessions of high-intensity interval exercise (6–7 bouts of 2 min; pause of 2 min) over a two-week period. Participants were allocated randomly into either a group that underwent CWI (11-min; 11 °C) or a group that performed passive recovery after each exercise session. Before the exercise sessions were performed, countermovement jump (CMJ) and heart rate variability were recorded (i.e., rMSSD, low and high frequency power and its ratio, SD1 and SD2). Exercise heart rate was calculated by recording the area under the curve (AUC) response. Internal session load was evaluated 30 min after each session. Blood concentrations of creatine kinase and lactate dehydrogenase were analyzed before the first visit and 24 h after the last sessions. Results: The CWI group presented higher rMSSD than the control group at each time point (group-effect P = 0.037). The SD1 was higher in CWI group when compared to the control group following the last exercise session (interaction P = 0.038). SD2 was higher in CWI group compared to the control group at each time point (group-effect P = 0.030). Both groups presented equal CMJ performance (P > 0.05), internal load (group-effect P = 0.702; interaction P = 0.062), heart rate AUC (group-effect P = 0.169; interaction P = 0.663), and creatine kinase and lactate dehydrogenase blood concentrations (P > 0.05). Conclusion: Repeated post-exercise CWI improves cardiac-autonomic modulation. However, no differences in neuromuscular performance, muscle damage markers, or session internal load were demonstrated between the groups. [ABSTRACT FROM AUTHOR]

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المؤلفون: Krueger, Malte, Costello, Joseph T., Stenzel, Mirko, Mester, Joachim, Wahl, Patrick

المصدر: European Journal of Applied Physiology; Jan2020, Vol. 120 Issue 1, p295-305, 11p, 1 Diagram, 3 Charts, 2 Graphs

مصطلحات موضوعية: PERFORMANCE standards, STANDARDS, TOURNAMENTS, CREATINE kinase, LACTATE dehydrogenase, INDUCED hypothermia, RESEARCH, MYALGIA, HOCKEY, RESEARCH methodology, WATER, EVALUATION research, MEDICAL cooperation, SLEEP, COMPARATIVE studies, RANDOMIZED controlled trials, EXERCISE, HEART beat, ATHLETIC ability

مستخلص: Purpose: This study examined the effects of daily post-exercise cold-water immersion (CWI) on match performance, perceptual recovery, and biomarkers of muscle damage and metabolic load during a 5-day international tournament of elite youth field-hockey players.Methods: The entire German under-18 national squad (n = 18) was randomly assigned to a daily CWI- (5-min at ~ 6 °C; excluding the head; n = 9) or passive recovery (CON; n = 9) intervention. Training and match performance were assessed using a GPS-tracking system and perceived exertion (RPE). Daily ratings of delayed onset muscle soreness (DOMS), perceived stress and recovery, quality of sleep, heart-rate recovery and serum creatine kinase (CK), lactate dehydrogenase, and urea nitrogen were also recorded. Repeated-sprint ability (RSA) and counter-movement jump (CMJ) were carried out on days 1 and 5.Results: There was no significance between intervention differences in time-on pitch, total distance, velocity zones, and accelerometer-base parameters during match performance (all p > 0.05). DOMS (p < 0.01), RPE (p < 0.01), and CK (p < 0.01) were significantly elevated over the course of the tournament; however, no between-intervention effects were observed (all p > 0.05). Both groups were able to maintain RSA and CMJ (all p > 0.05).Conclusion: In conclusion, daily post-exercise CWI did not improve match performance, perceptual recovery, or biomarkers of muscle damage and metabolic load in elite youth field-hockey players. [ABSTRACT FROM AUTHOR]

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المؤلفون: Bartolomei, Sandro, Sadres, Eliahu, Church, David, Arroyo, Eliott, III, Joseph, Varanoske, Alyssa, Wang, Ran, Beyer, Kyle, Oliveira, Leonardo, Stout, Jeffrey, Hoffman, Jay, Church, David D, Iii, Joseph A Gordon, Varanoske, Alyssa N, Beyer, Kyle S, Oliveira, Leonardo P, Stout, Jeffrey R, Hoffman, Jay R, Gordon, Joseph A III

المصدر: European Journal of Applied Physiology; Jul2017, Vol. 117 Issue 7, p1287-1298, 12p

مصطلحات موضوعية: ISOMETRIC exercise, MEN, EXERCISE, MALES, HYDROCORTISONE, LEG physiology, SKELETAL muscle physiology, C-reactive protein, COMPARATIVE studies, CONVALESCENCE, CREATINE kinase, INTERLEUKINS, LACTATE dehydrogenase, RESEARCH methodology, MEDICAL cooperation, MUSCLE contraction, MYALGIA, MYOGLOBIN, RESEARCH, TESTOSTERONE, EVALUATION research, RANDOMIZED controlled trials, SKELETAL muscle, RESISTANCE training

مستخلص: Purpose: The purpose of this study was to compare the physiological responses of a high-volume (HV; 8 sets of 10 repetitions) versus high-intensity (HI; 8 sets of 3 repetitions) exercise protocol in resistance-trained men.Methods: Twelve men (24.5 ± 4.2 years; 82.3 ± 8.4 kg; 175.2 ± 5.5 cm) with 6.3 ± 3.4 years of resistance training experience performed each protocol in a counterbalanced, randomized order. Performance [counter movement jump peak power (CMJP), isokinetic (ISOK) and isometric leg extension (MVIC), isometric mid-thigh pull (IMTP), and isometric squat (ISQ)] and muscle morphological [cross-sectional area (CSA) of vastus lateralis] assessments were performed at baseline (BL), 30-min (P-30 min), 24-h (P-24 h), 48-h (P-48 h), and 72-h (P-72 h) post-exercise for each testing session. In addition, endocrine (testosterone and cortisol), inflammatory [interleukin-6 (IL-6) and C-reactive protein (CRP)], and markers of muscle damage [creatine kinase (CK), lactate dehydrogenase (LDH), and myoglobin (Mb)] were assessed at the same time points.Results: Significantly greater reductions in CMJP (p < 0.001), and peak torque during both ISOK (p = 0.003) and MVIC (p = 0.008) at P-30 min were detected in HV compared to HI protocol. MVIC was still impaired at P-72 h following the HV protocol, while no differences were noted following HI. Markers of muscle damage (LDH, CK, and Mb) were significantly elevated following both HV and HI (p < 0.05), while cortisol and IL-6 concentrations were significantly elevated at P-30 min following HV only (p < 0.001 and p < 0.05, respectively).Conclusions: Results indicate that high-volume resistance exercise results in greater performance deficits, and a greater extent of muscle damage, than a bout of high-intensity resistance exercise. [ABSTRACT FROM AUTHOR]

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المؤلفون: Gee, Thomas, French, Duncan, Howatson, Glyn, Payton, Stephen, Berger, Nicolas, Thompson, Kevin, Gee, Thomas I, French, Duncan N, Payton, Stephen J, Berger, Nicolas J, Thompson, Kevin G

المصدر: European Journal of Applied Physiology; Nov2011, Vol. 111 Issue 11, p2653-2662, 10p, 1 Diagram, 2 Charts, 1 Graph

مصطلحات موضوعية: STRENGTH training, ROWING, ROWERS, DYNAMOMETER, BARBELLS, CREATINE kinase, LACTATE dehydrogenase, DIAGNOSIS of muscle diseases, ATHLETIC ability, BLOOD testing, COMPARATIVE studies, EXERCISE tests, RESEARCH methodology, MEDICAL cooperation, MUSCLE strength, MUSCLE diseases, PHYSICAL fitness, RESEARCH, SPORTS, TIME, EVALUATION research, RANDOMIZED controlled trials, ERGOMETRY, RESISTANCE training

مستخلص: Rowers regularly undertake rowing training within 24 h of performing bouts of strength training; however, the effect of this practice has not been investigated. This study evaluated the impact of a bout of high-intensity strength training on 2,000 m rowing ergometer performance and rowing-specific maximal power. Eight highly trained male club rowers performed baseline measures of five separate, static squat jumps (SSJ) and countermovement jumps (CMJ), maximal rowing ergometer power strokes (PS) and a single 2,000 m rowing ergometer test (2,000 m). Subsequently, participants performed a high-intensity strength training session consisting of various multi-joint barbell exercises. The 2,000 m test was repeated at 24 and 48 h post-ST, in addition SSJ, CMJ and PS tests were performed at these time points and also at 2 h post-ST. Muscle soreness, serum creatine kinase (CK) and lactate dehydrogenase (LDH) were assessed pre-ST and 2, 24 and 48 h post-ST. Following the ST, there were significant elevations in muscle soreness (2 and 24 h, P < 0.01), CK (2, 24 and 48 h, P < 0.01), and LDH (2 h, P < 0.05) in comparison to baseline values. There were significant decrements across all time points for SSJ, CMJ and PS, which ranged between 3 and 10% (P < 0.05). However, 2,000 m performance and related measurements of heart rate and blood lactate were not significantly affected by ST. In summary, a bout of high-intensity strength training resulted in symptoms of muscle damage and decrements in rowing-specific maximal power, but this did not affect 2,000 m rowing ergometer performance in highly trained rowers. [ABSTRACT FROM AUTHOR]

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المؤلفون: Kyparos, Antonios, Sotiriadou, Sofia, Mougios, Vassilis, Cheva, Angeliki, Barbanis, Sotiris, Karkavelas, George, Arsos, Georgios, Albani, Maria, Matziari, Chrysoula

المصدر: European Journal of Applied Physiology; Oct2011, Vol. 111 Issue 10, p2557-2569, 13p, 1 Black and White Photograph, 2 Charts, 2 Graphs

مصطلحات موضوعية: THERAPEUTIC use of vitamin E, MUSCLE injuries, LABORATORY rats, SKELETAL muscle, INTRAPERITONEAL injections, THERAPEUTIC use of antioxidants, CREATINE kinase, LACTATE dehydrogenase, SKELETAL muscle injuries, ANIMAL experimentation, ANTIOXIDANTS, COMPARATIVE studies, DIETARY supplements, DRUG administration, RESEARCH methodology, MEDICAL cooperation, MUSCLE diseases, POSTURE, RATS, RESEARCH, RUNNING, STATISTICAL sampling, TIME, VITAMIN E, EVALUATION research

مستخلص: Antioxidant supplementation has been suggested to prevent exercise-induced muscle injury, but the findings are inconsistent. The objective of this study was to investigate the potential protective role of vitamin E treatment against eccentric exercise-induced muscle injury by examining morphological and functional alterations in rat soleus muscle after downhill running as well as muscle injury markers in the blood. Sixty adult male Wistar rats were randomly assigned to vitamin E-treated or placebo-treated groups studied at rest, immediately post-exercise or 48 h post-exercise (n = 10 per group). Vitamin E was administered by daily intraperitoneal injections of 100 mg/kg body mass of DL: -α-tocopheryl acetate for five consecutive days prior to exercise, resulting in the doubling of its plasma concentration. Downhill running resulted in significant (P < 0.05) changes in all injury markers for the placebo-treated rats at 0 and 48 h post-exercise. However, significantly smaller soleus muscle single-twitch tension (P (t)) and unfused (40 Hz) tetanic force, and greater plasma creatine kinase (CK) and lactate dehydrogenase (LD) activities compared with the control were found only immediately post-exercise for the vitamin E-treated rats (P < 0.05). Maximal tetanic force (P (o)) did not decline significantly compared to sedentary controls at neither time points measured. The vitamin E-treated rats had significantly (P < 0.05) higher soleus muscle P (t) immediately post-exercise than the placebo-treated rats as well as lower plasma CK and LD activity 48 h post-exercise. However, there was no difference in P (o) decline between groups at either time points measured. Vitamin E-treated rats had less pronounced morphological alterations in muscle in the immediate and 48-h post-exercise period. In conclusion, the effect of short-term vitamin E supplementation against eccentric exercise-induced muscle injury did not appear to be physiologically significant, because vitamin E failed to prevent the decline in the functional measure of P (o) compared to the placebo conditions. [ABSTRACT FROM AUTHOR]

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المؤلفون: Baroni, Bruno Manfredini, Leal Junior, Ernesto Cesar Pinto, De Marchi, Thiago, Lopes, André Luiz, Salvador, Mirian, Vaz, Marco Aurélio, Lopes, André Luiz, Vaz, Marco Aurélio

المصدر: European Journal of Applied Physiology; Nov2010, Vol. 110 Issue 4, p789-796, 8p, 1 Black and White Photograph, 2 Charts, 2 Graphs

مصطلحات موضوعية: PLACEBOS, MUSCLE injuries, LACTATE dehydrogenase, SERUM, KNEE, KNEE physiology, PREVENTIVE medicine, PAIN, SKELETAL muscle injuries, COMPARATIVE studies, CREATINE kinase, EXERCISE, RESEARCH methodology, MEDICAL cooperation, MUSCLE contraction, RESEARCH, EVALUATION research, RANDOMIZED controlled trials, SKELETAL muscle

مستخلص: The purpose of the present study was to determine the effect of low level laser therapy (LLLT) treatment before knee extensor eccentric exercise on indirect markers of muscle damage. Thirty-six healthy men were randomized in LLLT group (n = 18) and placebo group (n = 18). After LLLT or placebo treatment, subjects performed 75 maximal knee extensors eccentric contractions (five sets of 15 repetitions; velocity = 60° seg(-1); range of motion = 60°). Muscle soreness (visual analogue scale--VAS), lactate dehydrogenase (LDH) and creatine kinase (CK) levels were measured prior to exercise, and 24 and 48 h after exercise. Muscle function (maximal voluntary contraction--MVC) was measured before exercise, immediately after, and 24 and 48 h post-exercise. Groups had no difference on kineanthropometric characteristics and on eccentric exercise performance. They also presented similar baseline values of VAS (0.00 mm for LLLT and placebo groups), LDH (LLLT = 186 IU/l; placebo = 183 IU/l), CK (LLLT = 145 IU/l; placebo = 155 IU/l) and MVC (LLLT = 293 Nm; placebo = 284 Nm). VAS data did not show group by time interaction (P = 0.066). In the other outcomes, LLLT group presented (1) smaller increase on LDH values 48 h post-exercise (LLLT = 366 IU/l; placebo = 484 IU/l; P = 0.017); (2) smaller increase on CK values 24 h (LLLT = 272 IU/l; placebo = 498 IU/l; P = 0.020) and 48 h (LLLT = 436 IU/l; placebo = 1328 IU/l; P < 0.001) post-exercise; (3) smaller decrease on MVC immediately after exercise (LLLT = 189 Nm; placebo = 154 Nm; P = 0.011), and 24 h (LLLT = 249 Nm; placebo = 205 Nm; P = 0.004) and 48 h (LLLT = 267 Nm; placebo = 216 Nm; P = 0.001) post-exercise compared with the placebo group. In conclusion, LLLT treatment before eccentric exercise was effective in terms of attenuating the increase of muscle proteins in the blood serum and the decrease in muscle force. [ABSTRACT FROM AUTHOR]

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المؤلفون: Chapman, Dale W., Newton, M., McGuigan, M. R., Nosaka, K.

المصدر: European Journal of Applied Physiology; Oct2008, Vol. 104 Issue 3, p531-539, 9p, 4 Charts, 5 Graphs

مصطلحات موضوعية: OLDER men, DISEASE susceptibility, MUSCLES, FLEXOR tendons, MYALGIA, MUSCLE strength, YOUNG men, MUSCLE contraction, AGE distribution, COMPARATIVE studies, CONVALESCENCE, CREATINE kinase, ELBOW, EXERCISE, RANGE of motion of joints, LACTATE dehydrogenase, RESEARCH methodology, MEDICAL cooperation, MUSCLE diseases, PAIN, RESEARCH, TIME, ULTRASONIC imaging, EVALUATION research, PAIN measurement, SKELETAL muscle

مستخلص: Controversy exists concerning the susceptibility of elderly individuals to eccentric exercise-induced muscle damage. This study investigated the hypothesis that muscle damage induced by fast maximal lengthening contractions would be greater for old than young men. Ten old (64 +/- 4 years) and young (25 +/- 6 years) men performed 30 maximal voluntary lengthening contractions of the elbow flexors at an angular velocity of 210 degrees s(-1). Prior to exercise, no significant differences were evident between groups for criterion measures. A significant (P < 0.05) group x time interaction was found only for isometric strength and muscle soreness with the old group showing significantly slower recovery of strength and less development of soreness compared with the young group. These results did not support the hypothesis that old men would be more susceptible to muscle damage, but confirmed a previous study reporting that recovery of muscle strength was slower for old than young individuals. [ABSTRACT FROM AUTHOR]

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المؤلفون: Quan-Sheng Su, Ye Tian, Jian-Guo Zhang, Hui Zhang, Su, Quan-Sheng, Tian, Ye, Zhang, Jian-Guo, Zhang, Hui

المصدر: European Journal of Applied Physiology; Jun2008, Vol. 103 Issue 3, p275-283, 9p, 1 Chart, 4 Graphs

مصطلحات موضوعية: EXERCISE, ANTIOXIDANTS, ATHLETES, CREATINE kinase, MUSCLE strength, PHYSIOLOGY, PREVENTIVE medicine, ANTI-inflammatory agents, PHARMACEUTICAL encapsulation, COMPARATIVE studies, DIETARY supplements, DRUG administration, INTERLEUKINS, LACTATE dehydrogenase, RESEARCH methodology, MEDICAL cooperation, ORAL drug administration, PAIN, RESEARCH, RUNNING, SUPEROXIDE dismutase, TIME, EVALUATION research, PAIN measurement, RANDOMIZED controlled trials, SULFUR acids, BLIND experiment, SKELETAL muscle

مستخلص: To investigate the effects of allicin supplementation on exercise-induced muscle damage (EIMD), interleukin-6 (IL-6), and antioxidative capacity, a double-blinded, placebo-controlled study was conducted in well-trained athletes. Subjects were randomly assigned to an allicin supplementation group (AS group) and a control group, and received either allicin or placebo for 14 days before and 2 days after a downhill treadmill run. Plasma creatine kinase (CK), muscle-specific creatine kinase (CK-MM), lactate dehydrogenase (LDH), IL-6, superoxide dismutase (SOD), total antioxidative capacity (TAC), and perceived muscle soreness were measured pre and post exercise. AS group had significantly lower plasma levels of CK, CK-MM and IL-6, and reduced perceived muscle soreness after exercise, when compared with the control group. AS group also demonstrated a trend toward reducing plasma concentration of LDH after exercise (P = 0.08), although not statistically significant. Allicin supplementation induced a higher value of TAC at rest, and this higher value was maintained 48 h after exercise, however, there was no difference in SOD values after exercise between the two groups. The results suggested that allicin might be a potential agent to reduce EIMD. Further studies concerning anti-inflammatory and anti-oxidative effects of allicin on EIMD are needed. [ABSTRACT FROM AUTHOR]

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المؤلفون: Vaile, Joanna, Halson, Shona, Gill, Nicholas, Dawson, Brian

المصدر: European Journal of Applied Physiology; Mar2008, Vol. 102 Issue 4, p447-455, 9p, 1 Chart, 4 Graphs

مصطلحات موضوعية: HYDROTHERAPY, PHYSIOLOGIC strain, EXERCISE, WATER immersion, PERFORMANCE, MYALGIA, PAIN management, THIGH, SKELETAL muscle physiology, EDEMA, COMPARATIVE studies, CREATINE kinase, CROSSOVER trials, INTERLEUKINS, LACTATE dehydrogenase, RESEARCH methodology, MEDICAL cooperation, MOTOR ability, MUSCLE contraction, MYOGLOBIN, RESEARCH, STATISTICAL sampling, EVALUATION research, RANDOMIZED controlled trials, PHYSIOLOGY, THERAPEUTICS

مستخلص: This study independently examined the effects of three hydrotherapy interventions on the physiological and functional symptoms of delayed onset muscle soreness (DOMS). Strength trained males (n = 38) completed two experimental trials separated by 8 months in a randomised crossover design; one trial involved passive recovery (PAS, control), the other a specific hydrotherapy protocol for 72 h post-exercise; either: (1) cold water immersion (CWI: n = 12), (2) hot water immersion (HWI: n = 11) or (3) contrast water therapy (CWT: n = 15). For each trial, subjects performed a DOMS-inducing leg press protocol followed by PAS or one of the hydrotherapy interventions for 14 min. Weighted squat jump, isometric squat, perceived pain, thigh girths and blood variables were measured prior to, immediately after, and at 24, 48 and 72 h post-exercise. Squat jump performance and isometric force recovery were significantly enhanced (P < 0.05) at 24, 48 and 72 h post-exercise following CWT and at 48 and 72 h post-exercise following CWI when compared to PAS. Isometric force recovery was also greater (P < 0.05) at 24, 48, and 72 h post-exercise following HWI when compared to PAS. Perceived pain improved (P < 0.01) following CWT at 24, 48 and 72 h post-exercise. Overall, CWI and CWT were found to be effective in reducing the physiological and functional deficits associated with DOMS, including improved recovery of isometric force and dynamic power and a reduction in localised oedema. While HWI was effective in the recovery of isometric force, it was ineffective for recovery of all other markers compared to PAS. [ABSTRACT FROM AUTHOR]

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المؤلفون: Costa, Andreas, Dalloul, Hicham, Hegyesi, Hargita, Apor, Peter, Csende, Zsolt, Racz, Levente, Vaczi, Mark, Tihanyi, Jozsef

المصدر: European Journal of Applied Physiology; Nov2007, Vol. 101 Issue 4, p427-436, 10p, 1 Chart, 5 Graphs

مصطلحات موضوعية: GENE expression, GENETIC regulation, MESSENGER RNA, DYNAMOMETER, DEHYDROGENASES, ANALYSIS of variance, MATHEMATICAL statistics, CELL differentiation, SKELETAL muscle physiology, BIOCHEMISTRY, CELL physiology, COMPARATIVE studies, CREATINE kinase, DNA, EXERCISE, GROWTH factors, LACTATE dehydrogenase, PHENOMENOLOGY, RESEARCH methodology, MEDICAL cooperation, MUSCLE contraction, MUSCLE proteins, MUSCLE strength, PHOSPHOTRANSFERASES, POLYMERASE chain reaction, RESEARCH, RNA, TUMOR markers, EVALUATION research, REVERSE transcriptase polymerase chain reaction, SKELETAL muscle, PHYSIOLOGY

مستخلص: Evidence indicates that repeated-bouts of eccentric exercise (EE) do not exacerbate the extent of muscle damage indices, as compared to a single-bout. We hypothesized that molecular adaptations, under repeated-bouts of EE, would include suppression of muscle repair inhibitory factors such as myostatin and up-regulation of muscle repair positive regulatory factors such as myogenic regulatory factors (MRFs). Fifteen males were recruited for this study. The exercise group (n=9) successfully completed six sets of 15 reps of maximum voluntary eccentric contractions, for six consecutive days, using a dynamometer (Multicont-II). Blood and muscle biopsy samples were obtained from each subject 1 week prior to exercise, 2 days post the first training session, and 24 h after the last training session. Gene expression levels were determined using real-time RT-PCR. Blood samples were analyzed for creatine kinase (CK) and lactate-dehydrogenase (LDH) activity. Repeated-bouts of EE induced a large down-regulation of myostatin mRNA (-73%) which persisted throughout the study. The responses of MRFs were mild. At day 3 only myogenin increased significantly (1.9 fold) while MyoD decreased by 45%. Surprisingly, at day 7, despite the presence of muscle damage indices, all MRFs returned to the pre-exercise levels. The results of the present study showed that repeated-bouts of EE, for six consecutive days, dramatically decreased Myostatin mRNA expression but impaired the expression patterns of MRFs such that, with the exception of myogenin that showed a moderate non-sustained increase, MyoD and MYf5 response was minimal. [ABSTRACT FROM AUTHOR]

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