Int J Sports Med 2003; 24(6): 410-418
DOI: 10.1055/s-2003-41171
Physiology & Biochemistry
© Georg Thieme Verlag Stuttgart · New York

Acute Hormonal and Neuromuscular Responses and Recovery to Forced vs. Maximum Repetitions Multiple Resistance Exercises

J.  P.  Ahtiainen1 , A.  Pakarinen2 , W.  J.  Kraemer3 , K.  Häkkinen1
  • 1Neuromuscular Research Center & Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
  • 2Department of Clinical Chemistry, University of Oulu, Oulu, Finland
  • 3The Human Performance Laboratory, Department of Kinesiology, The University of Connecticut, Storrs, CT, USA
Further Information

Publication History

Accepted after revision: November 20, 2002

Publication Date:
07 August 2003 (online)

Abstract

Acute hormonal and neuromuscular responses and recovery three days after the exercises were examined during the maximum repetitions (MR) and forced repetitions (FR) resistance exercise protocols in 16 male athletes. MR included 4 sets of leg presses, 2 sets of squats and 2 sets of knee extensions (with 12 RM) with a 2-min recovery between the sets and 4 min between the exercises. In FR the initial load was chosen to be higher than in MR so that the subject could not lift 12 repetitions per set by himself. After each set to failure the subject was assisted to perform the remaining repetitions to complete the 12 repetitions per set. Thus the exercise intensity was greater in FR than in MR. Both loading protocols led to the great acute increases (p < 0.05 - 0.001) in serum testosterone, free testosterone, cortisol and GH concentrations. However, the responses in cortisol (p < 0.05) and GH (p < 0.01) were larger in FR than in MR. The decrease of 56.5 % (p < 0.001) in maximal isometric force in FR was greater (p < 0.001) than that of 38.3 % in MR (p < 0.001) and force remained lower (p < 0.01) during the recovery in FR compared to MR. The larger decrease in isometric strength in FR than in MR was also associated with the decreased maximal voluntary EMG of the loaded muscles. The data indicate that the forced repetition exercise system induced greater acute hormonal and neuromuscular responses than a traditional maximum repetition exercise system and therefore it may be used to manipulate acute resistance exercise variables in athletes.

References

J. Ahtiainen

Department of Biology of Physical Activity · University of Jyväskylä

P.O. Box 35 · 40014 University of Jyväskylä · Finland ·

Phone: +358-14-2602083

Fax: +358-14-2602071

Email: [email protected]