Monozygous twin pairs (two female and four male) were used in a strength training study so that one member of each pair served as training subject (TS) and the other members as nonexercising controls (CS). TS trained four times a week for 12 weeks with maximal isometric knee extensions of the right leg. The parameters studied included muscle strength, endurance time, electromyographic activity, and activities of several key enzymes in nonoxidative and oxidative muscle metabolism. The results disclosed that in addition to a 20% increase in isometric knee extension strength in the trained leg of TS, an average increase of 11% was observed in strength of TS untrained leg. CS did not demonstrate any change in muscle strength. Training also included an improvement in the maintenance of a static load of 60% of the pretraining maximum. Increase in the maximum integrated electromyographic activity (IEMG) of the rectus femoris muscle occurred concomitantly with the knee extension strength. Training also caused reduction in the IEMG/tension ratio at submaximal loads indicating a more economical usage of the rectus femoris muscle. Muscle biopsies taken from the vastus lateralis muscle showed that the enzyme activities of MDH, SDH, and HK were higher, and LDH and CPK lower in the trained leg as compared to the nontrained control leg of TS or to the values of the untrained member of the twin pair. It is concluded that isometric strength training as used in the present study can cause increased recruitment of the available motor unit pool, improved efficiency at submaximal loads, and surprisingly also enchancement of the oxidative metabolism in the muscle.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Bendat, J. S., Piersol, A. G.: Random data: Analysis and measurement procedures. New York: Wiley 1971
Bergström, J.: Muscle electrolytes in man. Scand. J. Clin. Lab. Invest. (Suppl.) 68 (1962)
Friedeboldt, G., Nüssgen, W., Stoboy, H.: Die VerÄnderung der elektrischen AktivitÄt der Skelettmuskulatur unter den Bedingungen eines isometrischen Trainings. Z. Ges. Exp. Med. 129, 401–411 (1957)
Hellebrandt, F. A., Parrish, A. M., Houtz, S. J.: Influence of unilateral exercise on contralateral limb. Arch. Phys. Med. Rehabil. 28, 76 (1947)
Klissouras, V., Weber, G.: Training, growth and heredity. 4th International Symposium on Paediatric Work Physiology, Wingate, Israel, April 1972
Komi, P. V., Buskirk, E. R.: Reproducibility of electromyographic measurements with inserted wire electrodes and surface electrodes. Electromyogr. Clin. Neurophysiol. 4, 357–367 (1970)
Komi, P. V., Buskirk, E. R.: Effect of eccentric and concentric muscle conditioning on tension and electrical activity of human muscle. Ergonomics 15, 417–434 (1972)
Komi, P. V., Klissouras, V., Karvinen, E.: Genetic variation in neuromuscular performance. Int. Z. Angew. Physiol. 31, 289–304 (1973)
Komi, P. V., Viitasalo, J. H. T.: Signal characteristics of EMG at different levels of muscle tension. Acta Physiol. Scand. 96, 267–276 (1976)
Komi, P. V., Viitasalo, J. H. T., Havu, M., Thorstensson, A., Sjödin, B., Karlsson, J.: Skeletal muscle fibres and muscle enzyme activities in monozygous and dizygous twins of both sexes. Acta Physiol. Scand. 100, 385–392 (1977)
Kornberg, A.: Lactic dehydrogenase of muscle. In: Methods in Enzymology, Vol. I (S. P. Colowick, N. O. Kaplan, eds.), pp. 441–443. New York, London: Academic Press 1955
Kruse, R. D., Matthews, D. K.: Bilateral effects of unilateral exercise: Experimental study based on 120 subjects. Arch. Phys. Med. Rehabil. 39, 371 (1958)
Kwatny, E., Thomas, D. H., Kwatny, H. G.: An application of signal processing techniques to the study of myoelectric signals. IEEE Trans. Biomed. Eng. 17, 303–312 (1970)
Lang, A. H., Nurkkanen, P., Vaahtoranta, K. M.: Automatic sampling and averaging of electromyographic unit potentials. Electroencephalogr. Clin. Neurophysiol. 31, 404–406 (1971)
Lowry, H. O., Rosenbrough, N. J., Farr, A. L., Randall, R. J.: Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193, 265–275 (1951)
Meller, W., Mellerowics, H., Rocher, L., Stoboy, H.: The effect of training with equal physical power but different work in identical twins. XVIIIth World Congress of Sports Medicine, Oxford, England, September 1970
Müller, E. A.: Regulation of muscular strength. J. Ass. Phys. Ment. Rehab. 11, 41 (1957)
Ochoa, S.: Malic dehydrogenase from pig heart. In: Methods in Enzymology, Vol. I, (S. P. Colowick, N. O. Kaplan, eds.), pp. 735–739. New York, London: Academic Press 1955
Panin, N., Lindenauer, H. J., Weiss, A. A., Ebel, A.: Electromyographic evaluation of the “cross exercise” effect. Arch. Phys. Med. Rehabil. 42, 47–53 (1961)
Pennington, R. J.: Biochemistry of dystrophic muscle. Mitochondrial succinate tetrazolium reductase and ATPase. Biochem. J. 80, 649–654 (1961)
Roy, R., Ho, K., Taylor, J., Heusner, W., Van Huss, W.: Alterations in a histochemical profile induced by weight-lifting exercise. Med. Sci. Sports 9, 65 (1977)
Silberberg, R., Stamp, W. G., Lesker, P. A., Hasler, M.: Aging changes in ultrastructure and enzymatic activity of articular cartilage of guinea pigs. J. Gerontol. 25, 184–198 (1970)
Slater-Hammel, A. T.: Bilateral effects of muscle activity. Res. Q. Am. Assoc. Health Phys. Educ. 21, 203 (1950)
Thorstensson, A., Karlsson, J., Viitasalo, J. H. T., Luhtanen, P., Komi, P. V.: Effect of strength training on EMG of human skeletal muscle. Acta Physiol. Scand. 98, 232–236 (1976)
Viitasalo, J. H. T., Komi, P. V.: Signal characteristics of EMG with special reference to reproducibility of measurements. Acta Physiol. Scand. 93, 531–539 (1975)
This study was supported in part by a grant (9287/79/72) from the Ministry of Education (Finland)
About this article
Cite this article
Komi, P.V., Viitasalo, J.T., Rauramaa, R. et al. Effect of isometric strength training on mechanical, electrical, and metabolic aspects of muscle function. Europ. J. Appl. Physiol. 40, 45–55 (1978). https://doi.org/10.1007/BF00420988
- Strength training
- Enzyme activities