EFFECT OF MODERATE INCREMENTAL EXERCISE, PERFORMED IN FED AND FASTED STATE ON CARDIO-RESPIRATORY VARIABLES AND LEPTIN AND GHRELIN CONCENTRATIONS IN YOUNG HEALTHY MEN

Background: Although hormonal responses to exercise performed in fed state are well documented, far less in known about the effect of a single exercise bout, performed after overnight fasting, on cardio-respiratory responses and hormones secretion. It has been reported that recently discovered hormones as leptin and ghrelin may affect cardiovascular responses at rest. However, their effect on the cardiovascular responses to exercise is unknown. Aims: This study was designed to determine the effect of overnight fasting on cardio- respiratory responses during moderate incremental exercise. We have hypothesised that fasting / exercise induced changes in plasma leptin / ghrelin concentrations may influence cardiovascular response. Material and Methods: Eight healthy non-smoking men (means ± SE.: age 23.0 ± 0.5 years; body mass 71.9 ± 1.5 kg; height 179.1 ± 0.8 cm; BMI 22.42 ± 0.49 kg. m-2 with VO2max of 3.71 ± 0.10 l. min-1) volunteered for this study. The subjects performed twice an incremental exercise test, with the increase of power output by 30 W every 3 minutes. Tests were performed in a random order: once in the feed state- cycling until exhaustion and second, about one week later, after overnight fasting- cycling until reaching 150 W. Results: In the presen