The appetite-regulatory response to an acute session of high-intensity interval training in pre-menopausal and post-menopausal females

Sex hormones may affect the appetite response to exercise, and menopause, characterized by their withdrawal provides an opportunity to explore their role in appetite regulation. Therefore, this study compared the appetite-regulatory response to a high-intensity interval training (HIIT) session in pre- and post-menopausal females. Post-menopausal females (n=11; 58±2 y) completed one HIIT (10 ×1 min at 90% heart rate maximum with 1 min rest) and one no-exercise control (CTRL) session (study 1), while pre-menopausal females (n=11; 44±4 y) completed the same HIIT session in the LP and were compared to the post-menopausal HIIT session (study 2). Acylated ghrelin, active glucagon-like peptide-1 (GLP-1), lactate, and subjective appetite perceptions were measured across 4 timepoints. Energy intake was assessed for a 2-day period (day before, day of). In study 1, there was a main effect of group where acylated ghrelin was lower following HIIT versus CTRL (P=0.011, η p 2 =0.534) coinciding with a lower area under the curve (P=0.007, d =0.57), with no between-session differences in other appetite-regulatory markers (P>0.432, η p 2 <0.063). In study 2, acylated ghrelin was greater in pre- versus post-menopausal at 30- and 90-min post-exercise (P<0.081, d >0.66) with no differences in other appetite-regulatory parameters between groups (P>0.319, η p 2 <0.103), though lactate immediately post-exercise was ~2.25 mmol·L -1 in post-menopausal, and ~0.93 mmol·L -1 in pre-menopausal females which is lower than previously reported in other populations. These data support the potential role of sex hormones in blunting the exercise-induced suppression of acylated ghrelin, though no effect on anorexigenic hormones, appetite perceptions, or energy intake was present.