Age effects on growth hormone and testosterone responses to endurance exercise in patients with neuromuscular diseases

We have investigated the effect of age on the changes in growth hormone (GH ) and testosterone induced by muscular exercise in patients with neuromuscu lar diseases, by means of a test procedure which maintained compatibility. We investigated 21 control subjects and 36 patients. We found a significant increase in GH concentrations (+ 329%; p < 0.0001) after 20 min of exercis e on a bicycle ergometer. Testosterone concentrations showed no significant change. There was a significant negative correlation between the GH level after exercise and the age of the patients (R = -0.3, p = 0.015). The influ ence of increasing age on the GH reaction in patients with neuromuscular di sease is substantial and could have a significant influence on muscle mass, muscle strength and the time at which decompensation occurs in elderly pat ients with neuromuscular diseases. (C) 1999 Elsevier Science Ireland Ltd. A ll rights reserved.