Moderate-intensity combined training (RAT) acutely boosts PYY and alters appetite perception more than high-intensity functional training in men with obesity

Obesity is a complex metabolic disease characterized by excessive body fat accumulation, often driven by dysregulated appetite. Gut hormones, such as Peptide YY (PYY) and Glucagon-like Peptide-1 (GLP-1), play crucial roles in appetite regulation by signaling satiety to the brain. While exercise is a cornerstone of obesity management, the specific impact of different combined training modalities (resistance + aerobic) on acute gut hormone responses and subjective appetite in individuals with obesity remains underexplored. Understanding these acute physiological shifts could inform more effective exercise prescriptions.

This randomized crossover study involved 21 men with obesity who completed two distinct combined training protocols. Participants underwent either moderate-intensity resistance plus aerobic training (RAT) or high-intensity functional plus aerobic training (FAT). Subjective appetite was assessed using a visual analogue scale, while plasma levels of insulin, GLP-1, and PYY were measured at pre-exercise, immediately post-exercise, and 1 hour post-exercise. Energy intake was meticulously recorded for subsequent meals on the trial day and the following day, serving as a primary endpoint.

The study revealed significant differences in PYY responses between the two exercise conditions over time, indicated by a significant condition × time interaction (P=0.015). Specifically, at 1 hour post-exercise, PYY concentrations were substantially higher after RAT compared to FAT. The area under the curve (AUC) for PYY was also 1.44 times higher in RAT than in FAT (P=0.016). Subjective appetite perceptions also varied: fullness AUC was lower after RAT than after FAT (Δ -670.0 mm·120 min; P=0.014), while prospective food consumption AUC was higher after RAT than after FAT (Δ 701.4 mm·120 min; P=0.016). No significant between-condition differences were observed in total energy intake on either the trial day or the subsequent day. > PYY concentrations were 1.69 times higher after RAT than after FAT at 1 hour post-exercise (95% CI 1.26-2.27; adjusted P<0.001).