Hormonal and metabolic responses to slow movement resistance exercise with different durations of concentric and eccentric actions.

Author(s): Goto K, Ishii N, Kizuka T, Kraemer RR, Honda Y, Takamatsu K

Affiliation(s): Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama 359-1192, Japan. kgoto@aoni.waseda.jp

Publication date & source: 2009-07, Eur J Appl Physiol., 106(5):731-9. Epub 2009 May 10.

Publication type: Randomized Controlled Trial; Research Support, Non-U.S. Gov't

We examined hormonal responses to slow movement exercise involving concentric (CON) and eccentric (ECC) actions. Nine men performed knee extension exercises: (1) low-intensity exercise with slow CON contractions (5-1; 5 s for CON and 1 s for ECC); (2) low-intensity exercise with slow ECC contractions (1-5; 1 s for CON and 5 s for ECC); (3) low-intensity exercise with slow CON and ECC contractions (3-3; 3 s for each contraction); and (4) high-intensity exercise at normal velocity (1-1; 1 s for each contraction). Lactate concentration was significantly higher after the 5-1 than after the 1-5 (P < 0.05). Slow movement exercises significantly raised the concentrations of plasma epinephrine, serum growth hormone, and free testosterone (P < 0.05). Serum growth hormone concentration increased to a greater extent after the three slow movement trials compared with the normal movement trial (1-1). However, serum cortisol concentration was significantly higher after the 5-1 than after the 1-5 and 1-1 (P < 0.05). Average [Formula: see text] throughout the exercise session (divided by the time to complete exercise session) was significantly higher in the 1-1 (P < 0.05), with no significant difference among the slow movement trials. In conclusion, low-intensity exercises with slow movement acutely increased anabolic hormone concentrations regardless of the time to complete CON and ECC actions. In contrast, low-intensity exercise with slower ECC action stimulated smaller changes in lactate and cortisol compared with low-intensity exercise with slower CON action.