Physical activity and dehydroepiandrosterone sulphate, insulin-like growth factor I and testosterone in healthy active elderly people.

Objective: to examine the association of physical activity and cardio-respiratory fitness with dehydroepiandrosterone sulphate (DHEAS), insulin-like growth factor I (IGF-I) and testosterone in healthy elderly people.

Design: cross-sectional study.

Setting: university research department and department of geriatric medicine.

Participants: 60 independent, community-dwelling elderly subjects (26 men and 34 women) aged 66-84 who volunteered to participate.

Measurements: physical activity was evaluated by the Questionnaire d'Activité Physique Saint-Etienne and expressed by three indices: mean habitual daily energy expenditure (MHDEE), daily energy expenditure (DEE) [comprising activities with intensities corresponding to at least three metabolic equivalents (MET; 3.5 ml.kg1 x min1 of oxygen consumption)] and sport activity. Cardio-respiratory fitness was expressed by maximal oxygen consumption (VO2max).

Results: In women, DHEAS correlated with VO2max (partial correlation: r=0.33; P=0.05), MHDEE (r=0.50; P=0.002), DEE > 3 METs (r=0.49; P=0.003) and sport activity (r=0.35; P=0.04) whereas IGF-I correlated with MHDEE (r=0.48; P=0.004). DHEAS was correlated with IGF-I (r=0.43; P < 0.02) and with testosterone (r=0.41; P < 0.02). No such correlation was found in men.

Conclusion: lower habitual physical activity is related to lower levels of circulating DHEAS and IGF-I independently of age and anthropometric measures. Lower maximal aerobic capacity is associated with lower DHEAS concentrations, in healthy elderly women.