Strength training enhances muscle mass

Strength training exercises boost the levels of hormones associated with enhanced muscle mass and function in men. These hormonal responses may create an optimal environment for the metabolic process leading to improved muscular function following a strength endurance program. Researchers from the Democritus University of Thrace in Komotini conducted a study, in which 8 men in their 60s and early 70s and 9 men in their early 20s performed a strength endurance resistance exercise program of 6 exercises The men performed 3 sets of each exercise 15 repetitions with a 90 second rest period between sets. The researchers measured testosterone, cortisol and growth hormone levels before exercise, immediately after exercise, and 15 minutes after the end of exercise. The strength training boosted metabolism, as evidenced by increased blood lactate concentrations in both younger and older men, with the highest increases seen in the younger men. In addition, testosterone and cortisol concentrations were markedly higher immediately and 15 minutes after strength training, relative to pre-exercise concentrations, in both younger and older men. Growth hormone levels also rose after resistance training in both age groups, although the increase was higher in the younger men. The findings suggest that a moderate intensity, high repetition resistance exercise protocol designed to boost strength endurance seems to be a sufficient stimulus to increase testosterone, growth hormone, and cortisol levels in men.