The torque-frequency relationship is impaired similarly following two bouts of eccentric exercise: No evidence of a protective 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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The repeated bout effect and heat shock proteins: intramuscular HSP27 and HSP70 expression following two bouts of eccentric exercise in humans

Acta Physiologica Scandinavica ◽

10.1046/j.1365-201x.2002.00922.x ◽

2002 ◽

Vol 174 (1) ◽

pp. 47-56 ◽

Cited By ~ 76

Author(s):

H. S. Thompson ◽

P. M. Clarkson ◽

S. P. Scordilis

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Eccentric Exercise ◽

Hsp70 Expression ◽

Repeated Bout Effect ◽

Shock Proteins ◽

Exercise In Humans ◽

Repeated Bout

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A contralateral repeated bout effect attenuates induction of NF-κB DNA binding following eccentric exercise

Journal of Applied Physiology ◽

10.1152/japplphysiol.00133.2013 ◽

2014 ◽

Vol 116 (11) ◽

pp. 1473-1480 ◽

Cited By ~ 16

Author(s):

Ling Xin ◽

Robert D. Hyldahl ◽

Stuart R. Chipkin ◽

Priscilla M. Clarkson

Keyword(s):

Dna Binding ◽

Eccentric Exercise ◽

Muscle Soreness ◽

Knee Extension ◽

Binding Activity ◽

Isokinetic Strength ◽

Repeated Bout Effect ◽

Dna Binding Activity ◽

Muscle Biopsies ◽

Repeated Bout

We investigated the existence of contralateral repeated bout effect and tested if the attenuation of nuclear factor-kappa B (NF-κB; an important regulator of muscle inflammation) induction following eccentric exercise is a potential mechanism. Thirty-one healthy men performed two bouts of knee extension eccentric exercise, initially with one leg and then with the opposite leg 4 wk later. Vastus lateralis muscle biopsies of both exercised and control legs were taken 3 h postexercise. Knee extension isometric and isokinetic strength (60°/sec and 180°/sec) were measured at baseline, pre-exercise, immediately postexercise, and 1/day for 5 days postexercise. Serum creatine kinase (CK) activity and muscle soreness were assessed at baseline and 1/day for 5 days postexercise. NF-κB (p65) DNA-binding activity was measured in the muscle biopsies. Isometric strength loss was lower in bout 2 than in bout 1 at 24, 72, and 96 h postexercise ( P < 0.05). Isokinetic strength (60°/s and 180°/s) was reduced less in bout 2 than in bout 1 at 72 h postexercise ( P < 0.01). There were no significant differences between bouts for postexercise CK activity or muscle soreness. p65 DNA-binding activity was increased following eccentric exercise (compared with the control leg) in bout 1 (122.9% ± 2.6%; P < 0.001) and bout 2 (109.1% ± 3.0%; P < 0.05). Compared with bout 1, the increase in NF-κB DNA-binding activity postexercise was attenuated after bout 2 ( P = 0.0008). Repeated eccentric exercise results in a contralateral repeated bout effect, which could be due to the attenuated increase in NF-κB activity postexercise.

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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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Contralateral Repeated Bout Effect of Eccentric Exercise of the Elbow Flexors

Medicine & Science in Sports & Exercise ◽

10.1249/mss.0000000000000991 ◽

2016 ◽

Vol 48 (10) ◽

pp. 2030-2039 ◽

Cited By ~ 22

Author(s):

TREVOR C. Chen ◽

HSIN-LIAN CHEN ◽

MING-JU LIN ◽

HUI-I YU ◽

KAZUNORI NOSAKA

Keyword(s):

Eccentric Exercise ◽

Repeated Bout Effect ◽

Elbow Flexors ◽

Repeated Bout

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Intensity of eccentric exercise, shift of optimum angle, and the magnitude of repeated-bout effect

Journal of Applied Physiology ◽

10.1152/japplphysiol.00425.2006 ◽

2007 ◽

Vol 102 (3) ◽

pp. 992-999 ◽

Cited By ~ 105

Author(s):

Trevor C. Chen ◽

Kazunori Nosaka ◽

Paul Sacco

Keyword(s):

Eccentric Exercise ◽

Voluntary Contraction ◽

Creatine Kinase Activity ◽

Male Students ◽

Significant Shift ◽

Repeated Bout Effect ◽

Optimum Angle ◽

Arm Circumference ◽

Angle Shift ◽

Repeated Bout

This study compared the effect of four different intensities of initial eccentric exercise (ECC1) on optimum angle shift and extent of muscle damage induced by subsequent maximal eccentric exercise. Fifty-two male students were placed into 100%, 80%, 60%, or 40% groups ( n = 13 per group), performing 30 eccentric actions of the elbow flexors of 100%, 80%, 60%, or 40% of maximal isometric strength [maximal voluntary contraction (MVC)] for ECC1, followed 2–3 wk later by a similar exercise (ECC2) that used 100% MVC load. MVC at six elbow joint angles, range of motion, upper arm circumference, serum creatine kinase activity, myoglobin concentration, and muscle soreness were measured before and for 5 days following ECC1 and ECC2. A rightward shift of optimum angle following ECC1 was significantly ( P < 0.05) greater for the 100% and 80% than for the 60% and 40% groups, and it decreased significantly ( P < 0.05) from immediately to 5 days postexercise. By the time ECC2 was performed, only the 100% group kept a significant shift (4°). Changes in most of the criterion measures following ECC1 were significantly greater for the 100% and 80% groups compared with the 60% and 40% groups. Changes in the criterion measures following ECC2 were significantly ( P < 0.05) greater for the 40% group compared with other groups. Although the magnitude of repeated bout effect following ECC2 was significantly ( P < 0.05) smaller for the 40% and 60% groups, all groups showed significantly ( P < 0.05) reduced changes in criterion measures following ECC2 compared with the ECC1 100% bout. We conclude that the repeated-bout effect was not dependent on the shift of optimum angle.

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The repeated-bout effect: influence on biceps brachii oxygenation and myoelectrical activity

Journal of Applied Physiology ◽

10.1152/japplphysiol.00191.2010 ◽

2011 ◽

Vol 110 (5) ◽

pp. 1390-1399 ◽

Cited By ~ 16

Author(s):

Makii Muthalib ◽

Hoseong Lee ◽

Guillaume Y. Millet ◽

Marco Ferrari ◽

Kazunori Nosaka

Keyword(s):

Eccentric Exercise ◽

Isometric Contraction ◽

Muscle Activation ◽

Near Infrared ◽

Biceps Brachii ◽

Oxygenation Index ◽

Repeated Bout Effect ◽

Myoelectrical Activity ◽

Total Hemoglobin ◽

Repeated Bout

This study investigated biceps brachii oxygenation and myoelectrical activity during and following maximal eccentric exercise to better understand the repeated-bout effect. Ten men performed two bouts of eccentric exercise (ECC1, ECC2), consisting of 10 sets of 6 maximal lengthening contractions of the elbow flexors separated by 4 wk. Tissue oxygenation index minimum amplitude (TOImin), mean and maximum total hemoglobin volume by near-infrared spectroscopy, torque, and surface electromyography root mean square (EMGRMS) during exercise were compared between ECC1 and ECC2. Changes in maximal voluntary isometric contraction (MVC) torque, range of motion, plasma creatine kinase activity, muscle soreness, TOImin, and EMGRMS during sustained (10-s) and 30-repeated isometric contraction tasks at 30% (same absolute force) and 100% MVC (same relative force) for 4 days postexercise were compared between ECC1 and ECC2. No significant differences between ECC1 and ECC2 were evident for changes in torque, TOImin, mean total hemoglobin volume, maximum total hemoglobin volume, and EMGRMS during exercise. Smaller ( P < 0.05) changes and faster recovery of muscle damage markers were evident following ECC2 than ECC1. During 30% MVC tasks, TOImin did not change, but EMGRMS increased 1–4 days following ECC1 and ECC2. During 100% MVC tasks, EMGRMS did not change, but torque and TOImin decreased 1–4 days following ECC1 and ECC2. TOImin during 100% MVC tasks and EMGRMS during 30% MVC tasks recovered faster ( P < 0.05) following ECC2 than ECC1. We conclude that the repeated-bout effect cannot be explained by altered muscle activation or metabolic/hemodynamic changes, and the faster recovery in muscle oxygenation and activation was mainly due to faster recovery of force.

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