A single session of low-volume high-intensity interval and moderate-intensity continuous exercise elicits a transient reduction in ghrelin levels, but not in post-exercise energy intake in obese men

OBJECTIVE: This study investigated the acute effects of high-intensity interval (HIIE) and moderate-intensity continuous (MICE) exercise on ghrelin levels in obese men. SUBJECTS AND METHODS: A total of 10 obese men (age 27.6 ± 1.8 years, body mass index 35.4 ± 4.5 kg/m², body fat 39.9 ± 2.1%) performed two exercise sessions in a randomized order: HIIE (10 × 1 min intervals at 90% of the maximal heart rate [HR(max)] interspersed by 1 min of active recovery) and MICE (20 min at 70% of the HR(max)). Ghrelin levels were assessed pre-, post- and 1h post-exercise, and energy intake was assessed 1h post-exercise through an ad libitum meal. RESULTS: HIIE and MICE showed a trend to decrease ghrelin levels immediately post-exercise (-14.1 ± 21.6% and −9.6 ± 23.8%, respectively, p = 0.07) and decreased 1h post-exercise (-12.7 ± 31.8% and −13.8 ± 21.7%, respectively, p < 0.05). No changes were observed for post-exercise energy intake (p > 0.05). There was a positive correlation between the change in ghrelin levels and post-exercise energy intake only for HIIE (r = 0.63, p = 0.05). CONCLUSION: In summary, a single session of HIIE and MICE elicits a reduction on ghrelin levels without changing post-exercise energy intake in obese men.