Biological sex differences in appetite regulation following an acute bout of sprint interval training

Previous studies exploring the impact of biological sex on exercise-induced appetite suppression are unclear as females have participated during the follicular phase when concentrations of hormones (estradiol and progesterone) are low. Therefore, this study investigated potential sex differences in exercise-induced appetite suppression following sprint interval training (SIT) in males and females tested in the mid-luteal phase (LP). Twelve males (24±3 y; 24.7±2.2 kg·m-2) and twelve females (22±3 y; 22.0±1.5 kg·m-2) completed one SIT session with females participating during their mid-LP. Acylated ghrelin, total peptide tyrosine tyrosine (PYY), active glucagon-like peptide-1 (GLP-1), and overall appetite perceptions were measured pre-exercise, 0-min, 30-min, and 90-min post-exercise. Acylated ghrelin was greater in females compared to males (p=0.096, d=0.71) and was suppressed 0-min post-exercise compared to other time points (p<0.001, d>0.96). Total PYY was greater in females compared to males (p=0.005, d=0.71) and there were no differences in active GLP-1 between sexes or across time (p>0.19, f<0.15). Appetite perceptions were suppressed 0-min post-exercise (p<0.016, d>0.98) compared to other time points and increased throughout the session (p<0.006, d>1.03) and iAUC was greater in females compared to males (p=0.078, d=0.76). Taken together these data demonstrate similar changes in appetite-regulating hormones and appetite perceptions in response to an acute bout of SIT in males and females with the exception, of appetite iAUC which warrants further investigation.