ACUTE HORMONAL RESPONSES TO HEAVY RESISTANCE EXERCISE IN MEN AND WOMEN AT DIFFERENT AGES

To examine acute endogenous hormonal responses to heavy resistance exe rcise eight young women (YW) and eight young men (YM) in the 30-year a ge group, seven middle-aged women (MW) and eight middle-aged men (MM) in the 50-year age group as well as eight elderly women (EW) and eight elderly men (EM) in the 70-year age group performed a heavy resistanc e exercise session with three different exercises (bench press, situp exercise and bilateral leg press). The relative loading intensity and volume of the exercise session were kept the same for each subject so that they performed each of the 5 sets of each exercise with the maxim al load possible for 10 repetitions per set (10 repetition maximum). T he recovery time between the sets was 3 minutes. The loading led to ac ute significant decreases in maximal isometric leg extension force by 19 +/- 7% (p < 0.001), 31 +/- 15% (p < 0.01) and by 14 +/- 12% (p < 0. 01) in YW, MW and EW, respectively, and by 24 +/- 16% (p < 0.01), 34 /- 9% (p < 0.001) and by 20 +/- 12% (p < 0.001) for YM, MM and EM, res pectively. The mean concentrations of serum testosterone and cortisol remained statistically unchanged for all female groups. Significant in creases took place in testosterone concentrations in YM (p < 0.05) and in MM (p < 0.01) and in cortisol in MM (p(0.01), while EM demonstrate d no change at all. Serum growth hormone (GH) increased in women both in YW from 3.6 +/- 3.4 to 11.7 +/- 8.2 mu g x l(-1) (p < 0.01) and in MW from 0.3 +/- 0.1 to 6.5 +/- 5.6 mu g x l(-1) (p < 0.05), while EW d emonstrated no change. In men GH concentrations increased in YM from 0 .1 +/- 0.1 to 21.2 +/- 18.1 mu g x l(-1) (p < 0.05) and in MM from 0.3 +/- 0.2 to 6.0 +/- 5.4 mu g x l(-1) (p < 0.05), while EM demonstrated no change. The primary results indicate that the response of GH conce ntrations to the same relative heavy resistance work load is greatly l owered with increasing age both in men and women, while acute response s in testosterone levels are minor.