Specific Effects of Eccentric Training on Muscular Fatigability

Abstract

This study was designed to test the hypothesis that an eccentric training period induces a reduction of neuromuscular fatigability following an eccentric exercise. Before (Pre-T) and after (Post-T) a 7-wks sub-maximal eccentric training, ten active males performed a fatiguing exercise consisting of five sets of ten maximal eccentric elbow flexions. Before (Pre-T-1 and Post-T-1) and after (Pre-T-2 and Post-T-2) each fatiguing exercise, the voluntary torque and its associated agonistic electromyographic activity (RMS), assessed at four angular velocities (-60° × s^-1; 0° × s^-1; 60° × s^-1; 240° × s^-1) were measured. The isometric voluntary activation level and twitch contractile properties were measured. The training period induced significant eccentric and isometric torque gains. While isometric and concentric torque decreases were similar Pre-T-2 and Post-T-2, the eccentric torque loss was significantly lower Post-T-2 than Pre-T-2 (-11.7 ± 10.2 % and -20.5 ± 6.5 %, respectively; p < 0.05). The reduction of the twitch maximal rate of torque rise was also significantly lower Post-T-2 (-49.4 ± 11.9 %) than Pre-T-2 (-65.2 ± 9.8 %) (p < 0.05). The loss of maximal voluntary activation and RMS were similar Pre-T-2 and Post-T-2. The present experiment showed that a 7-wks eccentric training period produced contraction-type specific adaptations that significantly reduced the exercise-induced torque loss during eccentric muscle actions.

Key words

Maximal voluntary torque - muscle fatigue - twitch contractile properties - electromyography

References

• 1 Aagaard P, Simonsen E B, Andersen J L, Magnusson S P, Halkaer-Kristensen J, Dyhre-Poulsen P. Neural inhibition during maximal eccentric and concentric quadriceps contraction: effects of resistance training.  J Appl Physiol. 2000;  89 2249-2257
• 2 Allen D G. Eccentric muscle damage: mechanisms of early reduction of force.  Acta Physiol Scand. 2001;  171 311-319
• 3 Clarkson P M, Nosaka K, Braun B. Muscle function after exercise-induced muscle damage and rapid adaptation.  Med Sci Sports Exerc. 1992;  24 512-520
• 4 Clarkson P M, Sayers S P. Etiology of exercise-induced muscle damage.  Can J Appl Physiol. 1999;  24 234-248
• 5 Ebbeling C B, Clarkson P M. Muscle adaptation prior to recovery following eccentric exercise.  Eur J Appl Physiol. 1990;  60 26-31
• 6 Friden J, Lieber R L. Segmental muscle fiber lesions after repetitive eccentric contractions.  Cell Tissue Res. 1998;  293 165-171
• 7 Fuglevand A J, Zackowski K M, Huey K A, Enoka R M. Impairment of neuromuscular propagation during human fatiguing contractions at submaximal forces.  J Physiol. 1993;  460 549-572
• 8 Gibala M J, MacDougall J D, Tarnopolsky M A, Stauber W T, Elorriaga A. Changes in human skeletal muscle ultrastructure and force production after acute resistance exercise.  J Appl Physiol. 1995;  78 702-708
• 9 Higbie E J, Cureton K J, Warren G L, Prior B M. Effects of concentric and eccentric training on muscle strength, cross-sectional area, and neural activation.  J Appl Physiol. 1996;  81 2173-2181
• 10 Hortogabyi T, Barrier J, Beard D, Braspennincx J, Koens P, Devita P, Dempsey L, Lambert J. Greater initial adaptations to submaximal muscle lengthening than maximal shortening.  J Appl Physiol. 1996;  81 1677-1682
• 11 Hortobagyi T, Houmard J, Fraser D, Dudek R, Lambert J, Tracy J. Normal forces and myofibrillar disruption after repeated eccentric exercise.  J Appl Physiol. 1998;  84 492-498
• 12 Ingalls C P, Warren G L, Williams J H, Ward C W, Armstrong R B. E-C coupling failure in mouse EDL muscle after in vivo eccentric contractions.  J Appl Physiol. 1998;  85 58-67
• 13 Komi P V, Buskirk E R. Effect of eccentric and concentric muscle conditioning on tension and electrical activity of human muscle.  Ergonomics. 1972;  15 417-434
• 14 Lapointe B M, Fremont P, Cote C H. Adaptation to lengthening contractions is independent of voluntary muscle recruitment but relies on inflammation.  Am J Physiol . 2002;  282 R323-R329
• 15 McHugh M P, Connolly D AJ, Eston R G, Gleim G W. Exercise-induced muscle damage and potential mechanisms for the repeated bout effect.  Sports Med. 1999;  27 157-170
• 16 McHugh M P, Connolly D AJ, Eston R G, Gartman E J, Gleim G W. Electromyographic analysis of repeated bouts of eccentric exercise.  J Sports Sci. 2001;  19 163-170
• 17 Michaut A, Pousson M, Babault N, van Hoecke J. Is eccentric exercise-induced torque decrease contraction-type dependent?.  Med Sci Sports Exerc. 2002;  34 1003-1008
• 18 Newham D J, McCarthy T, Turner J. Voluntary activation of human quadriceps during and after isokinetic exercise.  J Appl Physiol. 1991;  71 2122-2126
• 19 Nosaka K, Sakamoto K, Newton M, Sacco P. How long does the protective effect on eccentric exercise-induced muscle damage last?.  Med Sci Sports Exerc. 2001;  33 1490-1495
• 20 Nosaka K, Sakamoto K, Newton M, Sacco P. The repeated bout effect of reduced-load eccentric exercise on elbow flexor muscle damage.  Eur J Appl Physiol. 2001;  85 34-40
• 21 Nosaka K K, Newton M. Concentric or eccentric training effect on eccentric exercise-induced muscle damage.  Med Sci Sports Exerc. 2002;  34 63-69
• 22 Nosaka K, Newton M, Sacco P. Responses of human elbow flexor muscles to electrically stimulated forced lengthening exercise.  Acta Physiol Scand. 2002;  174 137-145
• 23 Pensini M, Martin A, Maffiuletti N A. Central versus adaptations following eccentric resistance training.  Int J Sports Med. 2002;  23 567-574
• 24 Proske U, Morgan D L. Muscle damage from eccentric exercise: mechanism, mechanical signs, adaptation and clinical applications.  J Physiol. 2001;  537 333-345
• 25 Seger J Y, Arvidsson B, Thorstensson A. Specific effects of eccentric and concentric training on muscle strength and morphology in humans.  Eur J Appl Physiol. 1998;  79 49-57
• 26 Vandenboom I, Grange R W, Houston M E. Threshold for force potentiation associated with skeletal myosin phosphorylation.  Am J Physiol. 1993;  265 C1456-C1462
• 27 Warren G L, Hermann K M, Ingalls C P, Masselli M R, Armstrong R B. Decreased EMG median frequency during a second bout of eccentric contractions.  Med Sci Sports Exerc. 2000;  32 820-829
• 28 Warren G L, Ingalls C P, Lowe D A, Armstrong R B. Excitation-contraction uncoupling: major role in contraction-induced muscle injury.  Exerc Sports Sci Rev. 2001;  29 82-87
• 29 Westerblad H, Allen D G, Lannergren J. Muscle fatigue: Lactic acid or inorganic phosphate the major cause?.  News Physiol Sci. 2002;  17 17-21