Can anyone help?
We have recently observed an increase in the amplitude of the quadriceps femoris twitch after 5 weeks of isometric strength training (performed by humans). Whilst this is not a unique (eg. Rich and Cafarelli, 2000) or particularly interesting finding, it is contrary to what some others have observed in other muscles after similar training programs. eg. Alway et al., (1989) observed that whole muscle twitches remained constant, whilst Sale et al., (1982) observed that they decreased after resistance training despite significant hypertrophy and voluntary strength gains. It has been suggested that these paradoxical observations can be explained by an increase in the compliance of series elastic structures.
Having turned to the literature, we have found only a single paper to support the theory that isometric resistance training results in increased series elastic compliance (Goubel and Marini, 1987 - who observed these changes in rats). We are aware of other papers that have dealt with changes in the SEC after dynamic training involving jump training and of studies that have dealt with passive muscle stiffness after isometric training (eg. Klinge et al., 1997), although this is not relevant to us.
Is anyone aware of other (more recent?) studies dealing with the issue of (isometric?) resistance training's influence on series elasticity?
Any suggestions would be greatly appreciated.
Tony Shield
Department of Exercise Science and Sports Management
Southern Cross University
References
Alway, S. E., MacDougall, J. D., and Sale, D. G., (1989). Contractile adaptations in the human triceps surae after isometric exercise. Journal of Applied Physiology, 66(6): 2725-2732.
Goubel, F., and Marini, J. F., (1987) Fibre type transition and stiffness modification of soleus muscle of trained rats. European Journal of Applied Physiology, Pflugers Archives. 410: 321-325.
Klinge, K., Magnusson, S. P., Simonsen, E. B., Aagaard, P., Klausen, K., and Kjaer, M., (1997). The effect of strength and flexibility training on skeletal muscle electromyographic activity, stiffness, and viscoelastic stress relaxation response. American Journal of Sports Medicine, 25(5): 710-716.
Rich, C., and Cafarelli, E., (2000). Submaximal motor unit firing rates after 8 wk of isometric resistance training. Medicine and Science in Sport and Exercise, 32(1): 190-196.
Sale, D. G., McComas, A. J., MacDougall, J. D., and Upton, A. R. M., (1982). Neuromuscular adaptation in human thenar muscles following strength training and immobilization. Journal of Applied Physiology, 53(2): 419-424.
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We have recently observed an increase in the amplitude of the quadriceps femoris twitch after 5 weeks of isometric strength training (performed by humans). Whilst this is not a unique (eg. Rich and Cafarelli, 2000) or particularly interesting finding, it is contrary to what some others have observed in other muscles after similar training programs. eg. Alway et al., (1989) observed that whole muscle twitches remained constant, whilst Sale et al., (1982) observed that they decreased after resistance training despite significant hypertrophy and voluntary strength gains. It has been suggested that these paradoxical observations can be explained by an increase in the compliance of series elastic structures.
Having turned to the literature, we have found only a single paper to support the theory that isometric resistance training results in increased series elastic compliance (Goubel and Marini, 1987 - who observed these changes in rats). We are aware of other papers that have dealt with changes in the SEC after dynamic training involving jump training and of studies that have dealt with passive muscle stiffness after isometric training (eg. Klinge et al., 1997), although this is not relevant to us.
Is anyone aware of other (more recent?) studies dealing with the issue of (isometric?) resistance training's influence on series elasticity?
Any suggestions would be greatly appreciated.
Tony Shield
Department of Exercise Science and Sports Management
Southern Cross University
References
Alway, S. E., MacDougall, J. D., and Sale, D. G., (1989). Contractile adaptations in the human triceps surae after isometric exercise. Journal of Applied Physiology, 66(6): 2725-2732.
Goubel, F., and Marini, J. F., (1987) Fibre type transition and stiffness modification of soleus muscle of trained rats. European Journal of Applied Physiology, Pflugers Archives. 410: 321-325.
Klinge, K., Magnusson, S. P., Simonsen, E. B., Aagaard, P., Klausen, K., and Kjaer, M., (1997). The effect of strength and flexibility training on skeletal muscle electromyographic activity, stiffness, and viscoelastic stress relaxation response. American Journal of Sports Medicine, 25(5): 710-716.
Rich, C., and Cafarelli, E., (2000). Submaximal motor unit firing rates after 8 wk of isometric resistance training. Medicine and Science in Sport and Exercise, 32(1): 190-196.
Sale, D. G., McComas, A. J., MacDougall, J. D., and Upton, A. R. M., (1982). Neuromuscular adaptation in human thenar muscles following strength training and immobilization. Journal of Applied Physiology, 53(2): 419-424.
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To unsubscribe send SIGNOFF BIOMCH-L to LISTSERV@nic.surfnet.nl
For information and archives: http://isb.ri.ccf.org/biomch-l
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