Effects of set-repetition configuration in eccentric exercise on muscle damage and the repeated bout effect

High intensity unaccustomed eccentric contractions result in weakness and power loss due to fatigue and muscle damage. Through the repeated bout effect (RBE), adaptations occur, then damage and weakness are attenuated following a subsequent bout. However, it is unclear whether the RBE protects peak power output. We investigated the influence of the RBE on power production and estimated fatigue- and damage-induced neuromuscular impairments following repeated high-intensity eccentric contractions. Twelve healthy adult males performed 5 sets of 30 maximal eccentric elbow flexions and repeated an identical bout 4 weeks later. Recovery was tracked over 7 days following both bouts. Reduced maximum voluntary isometric contraction torque, and increased serum creatine kinase and self-reported soreness indirectly inferred muscle damage. Peak isotonic power, time-dependent measures—rate of velocity development (RVD) and rate of torque development (RTD)—and several electrophysiological indices of neuromuscular function were assessed. The RBE protected peak power, with a protective index of 66% 24 hours after the second eccentric exercise bout. The protection of power also related to preserved RVD (R2=0.61, P<0.01) and RTD (R2=0.39, P<0.01). Furthermore, the RBE’s protection against muscle damage permitted the estimation of fatigue-associated neuromuscular performance decrements following eccentric exercise. Novelty Bullets • The repeated bout effect protects peak isotonic power. • Protection of peak power relates to preserved rates of torque and velocity development, but more so rate of velocity development. • The repeated bout effect has little influence on indices of neuromuscular fatigue.

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Effect of eccentric contraction velocity on muscle damage in repeated bouts of elbow flexor exercise

Applied Physiology Nutrition and Metabolism ◽

10.1139/h10-042 ◽

2010 ◽

Vol 35 (4) ◽

pp. 534-540 ◽

Cited By ~ 20

Author(s):

Renato Barroso ◽

Hamilton Roschel ◽

Carlos Ugrinowitsch ◽

Rubens Araújo ◽

Kazunori Nosaka ◽

...

Keyword(s):

Muscle Damage ◽

Eccentric Exercise ◽

Mixed Model ◽

Creatine Kinase Activity ◽

Repeated Bout Effect ◽

Full Extension ◽

Maximal Voluntary Isometric Contraction ◽

Mixed Model Analysis ◽

Contraction Velocity ◽

Repeated Bout

Eccentric exercise induces muscle damage, but controversy exists concerning the effect of contraction velocity on the magnitude of muscle damage, and little is known about the effect of contraction velocity on the repeated-bout effect. This study examined slow (60°·s–1) and fast (180°·s–1) velocity eccentric exercises for changes in indirect markers of muscle damage following 3 exercise bouts that were performed every 2 weeks. Fifteen young men were divided into 2 groups based on the velocity of eccentric exercise: 7 in the Ecc60 (60°·s–1) group, and 8 in the Ecc180 (180°·s–1) group. The exercise consisted of 30 maximal eccentric contractions of the elbow flexors at each velocity, in which the elbow joint was forcibly extended from 60° to 180° (full extension) on an isokinetic dynamometer. Changes in maximal voluntary isometric contraction strength, range of motion, muscle soreness, and plasma creatine kinase activity before and for 4 days after the exercise were compared in the 2 groups using a mixed-model analysis (group × bout × time). No significant differences between groups were evident for changes in any variables following exercise bouts; however, the changes were significantly smaller (p < 0.05) after the second and third bouts than after the first bout. These results indicate that the contraction velocity does not influence muscle damage or the repeated-bout effect.

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Muscle damage and inflammation after eccentric exercise: can the repeated bout effect be removed?

Physiological Reports ◽

10.14814/phy2.12648 ◽

2015 ◽

Vol 3 (12) ◽

pp. e12648 ◽

Cited By ~ 13

Author(s):

Nikos V. Margaritelis ◽

Anastasios A. Theodorou ◽

Vasilios Baltzopoulos ◽

Constantinos N. Maganaris ◽

Vassilis Paschalis ◽

...

Keyword(s):

Muscle Damage ◽

Eccentric Exercise ◽

Repeated Bout Effect ◽

Repeated Bout

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Variability in Muscle Damage After Eccentric Exercise and the Repeated Bout Effect

Research Quarterly for Exercise and Sport ◽

10.1080/02701367.2006.10599370 ◽

2006 ◽

Vol 77 (3) ◽

pp. 362-371 ◽

Cited By ~ 20

Author(s):

Trevor C. Chen

Keyword(s):

Muscle Damage ◽

Eccentric Exercise ◽

Repeated Bout Effect ◽

Repeated Bout

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Human alpha-actinin-3 genotype association with exercise-induced muscle damage and the repeated-bout effect

Applied Physiology Nutrition and Metabolism ◽

10.1139/h2012-087 ◽

2012 ◽

Vol 37 (6) ◽

pp. 1038-1046 ◽

Cited By ~ 21

Author(s):

Tomas Venckunas ◽

Albertas Skurvydas ◽

Marius Brazaitis ◽

Sigitas Kamandulis ◽

Audrius Snieckus ◽

...

Keyword(s):

Muscle Damage ◽

Eccentric Exercise ◽

Knee Extension ◽

Repeated Bout Effect ◽

Drop Jumps ◽

Jumping Exercise ◽

Exercise Induced ◽

Torque Values ◽

The Impact ◽

Repeated Bout

Alpha-actinin-3 (ACTN3) is an integral part of the Z line of the sarcomere. The ACTN3 R577X (rs1815739) polymorphism determines the presence or absence of functional ACTN3, which may influence the extent of exercise-induced muscle damage. This study aimed to compare the impact of, and recovery from, muscle-damaging eccentric exercise on subjects with or without functional ACTN3. Seventeen young men (20–33 years old), homozygous for the R (n = 9) or X (n = 8) alleles, performed two bouts of stretch–shortening exercise (50 drop jumps) two weeks apart. Muscle soreness, plasma creatine kinase (CK) activity, jump height, maximal voluntary isometric torque (MVC), peak concentric isokinetic torque (IT), and electrically stimulated knee extension torques at 20 and 100 Hz were measured at baseline and at a number of time points up to 14 days after each bout. There were no significant baseline differences between the groups. However, significant time point × genotype interactions were observed for MVC (p = 0.021) and IT (p = 0.011) for the immediate effect of eccentric exercise in bout 1. The RR group showed greater voluntary force decrements (RR vs. XX: MVC, –33.3% vs. –24.5%; IT, –35.9% vs. –23.2%) and slower recovery. A repeated-bout effect was clearly observed, but there were no differences by genotype group. The ACTN3 genotype modulates the response of muscle function to plyometric jumping exercise, although the differences are modest. The ACTN3 genotype does not influence the clearly observed repeated-bout effect; however, XX homozygotes recover baseline voluntary torque values faster and thus may be able to undertake more frequent training sesssions.

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