Testosterone, dehydroepiandrosterone, insulin-like growth factor 1, and insulin in sedentary and physically trained aged men

The influence of physical activity on dehydroepiandrosterone sulfate (DHEAS ), total and free testosterone (TT and FT, respectively), insulin-like grow th factor I (IGF-1), follicle-stimulating hormone (FSH), luteinizing hormon e (LH) and insulin concentrations in aging men was investigated. Eight trai ned and nine sedentary men aged 60-65 years volunteered to participate in t his study. Physical activity was determined during an effort test and evalu ated by the measure of the maximal aerobic power ((W)over dot(aer,max)). In the trained aging men, the (W)over dot(aer,max) was higher than in the sed entary group of matching age [mean (SD) 206.8 (17.1) W versus 136.6 (12.3) W; P < 0.0001]. The fat percentage was higher in the sedentary (n = 9) than in the trained (n = 8) group [23.9 (3.2)% versus 14.6 (3.7)%; P < 0.0001]. DHEAS and IGF-I levels were higher in trained than in sedentary subjects, respectively 2.04 (1) mu mol/l versus 1.01 (0.68) mu mol/l (P = 0.02) and 1 92.1 (40.1) ng/ml versus 132.8 (31.2) ng/ml (P = 0.003). Insulin levels wer e higher in sedentary subjects [11.2 (3.5) mIU/l versus 7.6 (2.2) mIU/l, P = 0.03]. No statistical difference was observed between both groups for FT and total TT values, FSH values and LH values. IGF-1 was correlated with (W )over dot(aer,max) (r = 0.64, P = 0.003), and DHEAS was correlated with IGF -1 (r = 0.59, P = 0.01). We observed a relationship between fat percentage and each of the following hormones: IGF-1 (r = -0.50, P = 0.03), FT (r = -0 .66, P = 0.002), TT(r = -0.54, P = 0.02) and insulin (r = 0.63, P = 0.004). Insulin was inversely correlated with FT (r -0.66, P 0.002) and TT (r = -0 .47, P = 0.05). These results suggest that regular physical activity could maintain higher DHEAS and IGF-l and lean body mass levels in elderly men, a nd participate in general well being in older age.