Effects of 75 min of weekly exercise snacks on body composition, cardiometabolic health, cardiorespiratory fitness, and lower-body explosive power in overweight and obese female university students

Abstract

Background Overweight and obesity have become increasingly prevalent among female university students, whereas conventional exercise interventions are often limited by poor adherence and time constraints. Exercise snacks (ES) may offer a flexible and time-efficient alternative; however, their effectiveness in this population remains unclear. Objective We compared the effects of 8 weeks of ES (75 min/week) and HIIT on body composition, cardiometabolic health, cardiorespiratory fitness, and lower-body explosive power in overweight and obese females in a real-world setting. Methods Thirty overweight and obese female university students were randomized to either the ES group or the high-intensity interval training (HIIT) group in an 8-week randomized controlled trial. Both groups completed 75 min of bodyweight exercise per week. Pre- and post-intervention assessments included body composition, cardiometabolic health, cardiorespiratory fitness, and lower-body explosive power. A two-way repeated measures ANOVA was used to analyze training effects, with Bonferroni post hoc tests. Effect sizes were reported as partial eta squared ( ηp2 ) or Cohen’s d, with significance set at p < 0.05. Results Compared with the HIIT group, the ES group showed significantly lower RPE throughout the intervention period (p < 0.05). Significant time effects were observed for body weight (p < 0.001, ηp2 = 0.59), BMI (p < 0.001, ηp2 0.60), body fat percentage (p < 0.001, ηp2 = 0.46), standing long jump performance (p < 0.001, ηp2 = 0.43), V̇O2max (p < 0.001, ηp2 = 0.47), SBP (p < 0.001, ηp2 = 0.54), TC (p = 0.004, ηp2 = 0.26), and LDL-C (p = 0.002, ηp2 = 0.30). A significant time × group interaction was observed for DBP (p = 0.02, ηp2 = 0.19), with a significant reduction in the HIIT group (p = 0.002, d = 0.86) but not in the ES group (p = 0.86, d = −0.04). No significant time effects were observed for TG (p = 0.96) or HDL-C (p = 0.10). Weekly mean RPE was significantly lower in the ES group than in the HIIT group throughout the intervention period. Conclusion In conclusion, in a real-world remote setting, 75 min/week of bodyweight-based ES may be a promising strategy that warrants confirmation in adequately powered randomized controlled trials.