Hormonal responses to repeated bouts of supramaximal cycle ergometer exertions

Abstract

Study aim: To determine hormonal (growth hormone, cortisol and testosterone in blood)responses to a series of supramaximal cycle ergometer exercise bouts. Material and methods:Seven physical education students were subjected to two series of exercises, 5 bouts each, spaced by one week. The load in the first bout in each series amounted to 100% of work output recorded previously in the Wingate test, all other bouts amounting to 50%. In Series A and B, the loads were 10 and 5% of body mass (BM), respectively. Individual bouts were separated by 2-min intervals. Growth hormone (GH), cortisol (C), testosterone (T) and blood pH were determined in fingertip blood before the exercise, following Bouts 3 and 5, and 30 min after the exercise was discontinued. Results: Growth hormone, cortisol and testosterone concentrations increased significantly after both series of exertions. Conclusions: Repeated bouts of sprint-like exertions may be applied to design training protocols involving the desired kind of stimulation of the hormonal control, considering the necessary external load and exercise duration.