The Effects of Different Exercise Intensity on Plasma Ghrelin, Glucose, and Insulin Levels

Abstract

The purpose of this study was to investigate the effects of acute exercise intensity on plasma ghrelin, glucose and insulin levels in middle aged women. Twenty-six middle aged women were randomly assigned to an exercise group(n=18) and a non-exercise group(n=8). The subjects in exercise group were further randomly assigned to moderate-intensity group(MIG) and vigorous-intensity group(VIG). The MIG and VIG groups performed treadmill running at intensities of 50 % and 80 % V ̇O2max, respectively, and the duration of exercise was individually adjusted to consume 400 kcal per session. Total ghrelin levels decreased significantly immediately after and 30-min recovery after vigorous treadmill running, with no such changes following either control or moderate treadmill running. Glucose levels did not change significantly immediately after either control or treadmill running and then they decreased significantly 30-min recovery after vigorous treadmill running, with no such changes following either control or moderate treadmill running. Insulin levels decreased significantly immediately after vigorous treadmill running and it returned to the baseline levels 30-min recovery after vigorous treadmill running, with no such changes following either control or moderate treadmill running. In conclusion, the findings of this study suggest that unlike moderate-intensity treadmill running, vigorous-intensity treadmill running can stimulate appetite via increased total ghrelin levels secondary to decreased glucose levels in middle-aged women.