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Effects of fatigue and recovery on electromyographic and isometric force- and relaxation-time characteristics of human skeletal muscle

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Summary

Effects of fatigue produced by a maintained 60% isometric loading on electromyographic and isometric force-time and relaxation-time characteristics of human skeletal muscle were studied in 21 males accustomed to strength training. Fatigue loading resulted in a slight but not significant change in the maximal integrated EMG of a maximal isometric contraction, and a large decrease (20.4±6.3%, p<0.001) in maximal force. Fatigue loading increased (p<0.05−0.01) neural activation of the muscles during rapidly produced submaximal isometric forces, but had a considerable adverse effect (p<0.001) on the corresponding force-time characteristics. Correlations between the relative changes after fatigue in the IEMG/force ratio at the maximal force level, and in the IEMG/force ratios of the early phases of the force-time curve were not significant, but gradually became significant (p<0.01) at higher force levels. The average IEMG of the muscles in the relaxation phase of contraction remained unaltered by fatigue, while a marked deleterious change in the relaxation-time variables (p<0.001) occurred concomitantly. During the subsequent 3 min rest period considerable (12.1±7.0%, p<0.001) recovery was noted in the maximal force, with smaller (insignificant or p<0.05−0.01) changes in the force-time and relaxation-time variables, while the average IEMG of force production decreased (p<0.01−0.001). The present findings suggest that fatigue leading to a worsening in force-time, in maximal force and in the relaxation-time parts of a maximal isometric contraction might take place primarily in the contractile processes.

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References

  • Bergström J (1962) Muscle electrolytes in man. Scand J Clin Lab Invest [Suppl] 68:11–13

    Google Scholar 

  • Brody IA (1976) Regulation of isometric contraction in skeletal muscle. Exp Neurol 50:673–683

    Google Scholar 

  • Gollnick P, Armstrong R, Saubert G, Piehl K, Saltin B (1972) Enzyme activity and fiber composition in skeletal muscle of untrained and trained men. J Appl Physiol 33:312–319

    Google Scholar 

  • Gydikov A, Kosarov D (1973) Physiological characteristics of the tonic and phasic motor units in human muscles. In: Gydikov AA, Tankov NT, Kosarov DS (eds) Motor control. Plenum Press, New York, pp 75–94

    Google Scholar 

  • HÄkkinen K, Komi PV (1983) Electromyographic and mechanical characteristics of human skeletal muscle during fatigue under voluntary and reflex conditions. Electroenceph Clin Neurophysiol 55:436–444

    Google Scholar 

  • HÄkkinen K, Komi PV (1985) Fatiguability in voluntary and reflex contraction after conditioning of human skeletal muscle. Electromyogr Clin Neurophysiol 25(5):319–330

    Google Scholar 

  • HÄkkinen K, Viitasalo JT, Komi PV (1980) Die Wirkung unterschiedlich kombinierter konzentrischer und exzentrischer Muskelarbeit auf Kraft-Zeit-Merkmale der Beinstreckmuskulatur. Leistungssport 10:374–381

    Google Scholar 

  • HÄkkinen K, Alén M, Komi PV (1985) Changes in isometric force- and relaxation-time, electromyographic and muscle fiber characteristics of human skeletal muscle during strength training and detraining. Acta Physiol Scand 125:573–585

    Google Scholar 

  • Hanson J (1974) The effects of repetitive stimulation on the action potential and twitch of rat muscle. Acta Physiol Scand 90:387–400

    Google Scholar 

  • Hashimoto I, Sembrowich WL, Gollnick PD (1978) Calcium uptake by isolated sarcoplasmic reticulum and homogenotes in different fiber types following exhaustive exercise. Med Sci Sports 10:42

    Google Scholar 

  • Komi PV (1973) A new electromechanical ergometer. In: Hauser G, Mellerowicz H (eds) 3. Int Seminar für Ergometrie, pp 173–176

  • Komi PV (1983) Electromyographic, mechanical and metabolic changes during static and dynamic fatigue. In: Knuttgen, Vogel, Poortmans (eds) Biochemistry of exercise, Int. Ser Sport Sciences, vol 13. Human Kinetics Publishers, Champaign, pp 197–215

    Google Scholar 

  • Komi PV (1984) Fatigue and recovery of neuromuscular function. In: Jokl E, Hebbelinck M (eds) Medicine Sport Sci, vol 17. Karger, Basel, pp 187–201

    Google Scholar 

  • Komi PV, Rusko H (1974) Quantitative evaluation of mechanical and electrical changes during fatigue loading of eccentric and concentric work. Scand J Rehab Med [Suppl] 3:121–126

    Google Scholar 

  • Komi PV, Viitasalo JT (1977) Changes in motor unit activity and metabolism in human skeletal muscle during and after repeated eccentric and concentric contrations. Acta Physiol Scand 100:246–254

    Google Scholar 

  • Komi PV, Tesch P (1979) EMG frequency spectrum, muscle structure and fatigue during dynamic contractions in man. Eur J Appl Physiol 42:41–52

    Google Scholar 

  • Kroll W, Clarkson P, Kamen G, Lambert J (1980) Muscle fibre type composition and knee extension isometric strength fatigue patterns in power- and endurance-trained males. Res Quart Exc Sport 51:323–333

    Google Scholar 

  • Larsson L (1978) Morphological and functional characteristics of the aging skeletal muscle in man. A cross-sectional study. Acta Physiol Scand [Suppl] 457:36p

    Google Scholar 

  • Laurig W (1970) Electromyographie als arbeitswissenschaftliche Unteruchungsmethode zur Beurteilung von statischer Muskelarbeit. Beuth Vertrieb, Berlin

    Google Scholar 

  • Lindström L, Magnusson R, Petersen I (1970) Muscular fatigue and action potential conduction velocity changes studied with frequency analysis of EMG signals. Electromyogr Clin Neurophysiol 10:341–356

    Google Scholar 

  • Lindström L, Kadefors R, Petersen I (1977) An electromyographic index for localized muscle fatigue. J Appl Physiol 43:750–754

    Google Scholar 

  • Mortimer J, Magnusson R, Petersen I (1970) Conduction velocity in ischemic muscle: effect on EMG frequency spectrum. Am J Physiol 219:1324–1329

    Google Scholar 

  • Nilsson J, Tesch P, Thorstensson A (1977) Fatigue and EMG of repeated fast voluntary contractions in man. Acta Physiol Scand 101:194–198

    Google Scholar 

  • Padykula H, Herman E (1955) The specificity of the histochemical method of adenosine triphosphatase. J Histochem Cytochem 3:170–195

    Google Scholar 

  • Person R, Kudina L (1972) Discharge frequency and discharge pattern of human motor units during voluntary contraction of muscle. Electroenceph Clin Neurophysiol 32:471–483

    Google Scholar 

  • Robertson SP, Kerrick WGL (1979) The effects of pH on Ca2+-activated force in frog skeletal muscle fibres. Pflügers Arch 380:41–45

    Google Scholar 

  • Sahlin K (1978) Intracellular pH and energy metabolism in skeletal muscle of man. Acta Physiol Scand [Suppl] 55

    Google Scholar 

  • Sandow A (1970) Skeletal muscle. Ann Rev Physiol 32:87–138

    Google Scholar 

  • Strass D (1985) Effects of fatigue on isometric force-time characteristics in human muscle. In: Biomechanics X, Abstract book. Arbete och hÄlsa, ventenskaplig skrift-serie 14:252

    Google Scholar 

  • Tesch P, Sjödin B, Thorstensson A, Karlsson J (1978) Muscle fatigue and its relation to lactate accumulation and LDH activity in man. Acta Physiol Scand 103:413–420

    Google Scholar 

  • Tesch PA, Komi PV, Jacobs I, Karlsson J, Viitasalo JT (1983) Influence of lactate accumulation on EMG frequency spectrum during repeated concentric contractions. Acta Physiol Scand 119:61–67

    Google Scholar 

  • Thorstensson A, Karlsson J (1976) Fatiguability and fibre composition of human skeletal muscle. Acta Physiol Scand 98:318–322

    Google Scholar 

  • Viitasalo JT, Komi PV (1975) Signal characteristics of EMG with special reference to reproducibility of measurements. Acta Physiol Scand 93:531–539

    Google Scholar 

  • Viitasalo J, Komi PV (1977) Signal characteristics of EMG during fatigue. Eur J Appl Physiol 37:111–121

    Google Scholar 

  • Viitasalo J, Komi PV (1978) Isometric endurance, EMG power spectrum, and fiber composition in human quadriceps muscle. In: Asmussen E, Jörgensen K (eds) Biomechanics VI-A. University Park Press, Baltimore, pp 244–250

    Google Scholar 

  • Viitasalo J, Komi PV (1980) EMG, reflex and reaction time components, muscle structure and fatigue during intermittent isometric contractions in man. Int J Sports Med 1:185–190

    Google Scholar 

  • Viitasalo J, MÄkinen P (1980) Comparison of five different methods for determination of muscle fibre areas. Presented at the Fifth Puijo Symposium, August 6–8, 1980. Kuopio, Finland (Poster)

    Google Scholar 

  • Viitasalo J, Komi PV (1981) Effects of fatigue on isometric force- and relaxation-time characteristics in human muscle. Acta Physiol Scand 111:87–95

    Google Scholar 

  • Viitasalo J, Saukkonen S, Komi PV (1980) Reproducibility of measurements of selected neuromuscular performance variables in man. Electromyogr Clin Neurophysiol 20:487–501

    Google Scholar 

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HÄkkinen, K., Komi, P.V. Effects of fatigue and recovery on electromyographic and isometric force- and relaxation-time characteristics of human skeletal muscle. Europ. J. Appl. Physiol. 55, 588–596 (1986). https://doi.org/10.1007/BF00423202

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