A135: 6-Week Intermittent Fasting and Aerobic Exercise: Effects on Body, Cardiovascular, and Sleep in Masked Obese Men

Abstract

Masked obesity (MO), defined by normal BMI with elevated body fat percentage, poses elevated health risks. This randomized trial compares combined intermittent fasting (IF) and aerobic exercise (AE) with single-modality interventions in young males, assessing body composition, cardiovascular function, and sleep quality to establish optimal evidence-based interventions. A total of 36 participants were randomized into three groups (n=12 each): (1) intermittent fasting combined with aerobic exercise (IF+AE), (2) IF-only, and (3) AE-only. Baseline assessments included body composition (weight, fat/lean mass, waist-to-hip ratio), cardiovascular markers (carotid intima-media thickness [CIMT], ejection fraction), and Pittsburgh Sleep Quality Index (PSQI). The IF+AE group alternated between two days of IF plus one day of AE weekly for the first 3 weeks, then reversed to two days of AE plus one day of IF weekly for the latter 3 weeks. The IF-only group followed a 6-week protocol with three non-consecutive fasting days weekly (20–25% daily caloric intake). The AE-only group performed 40–45 minutes of moderate treadmill walking (60–70% max heart rate) for 6 weeks. Statistical analysis used one-way ANOVA and t-tests P \u3c 0.05 significance threshold. All interventions maintained equivalent weekly intervention frequencies while differing in regimen composition. Body Composition: Normalization of MO: 33.3% (IF+AE), 16.7% (IF), and 16.7% (AE) of participants achieved normal body composition. Fat Mass and WHR: All groups showed significant reductions (P \u3c 0.05), with no between-group differences. Lean Mass: IF+AE exhibited a significant increase in lean mass (+0.33 kg, P \u3c 0.05) compared to IF (P \u3c 0.05), but not versus AE. Cardiovascular Function: Ejection Fraction: IF+AE (67.44±5.54% to 71.78±6.40%, P \u3c 0.05) and AE (63.29±8.36% to 67.14±9.55%, P \u3c 0.05) showed significant improvements, whereas IF exhibited no change. CIMT: No significant changes observed across groups. Sleep Quality (PSQI): IF+AE demonstrated superior outcomes in sleep latency and sleep continuity compared to IF (P \u3c 0.05), but no significant differences were observed between IF+AE and AE. The 6-week IF combined with moderate aerobic exercise (IF+AE) synergistically improved outcomes in young men with MO. IF+AE enhanced lean mass retention, ejection fraction, and sleep quality versus isolated IF, while achieving fat reduction comparable to AE alone. This combination optimized metabolic and cardiovascular benefits without lean mass loss, supporting its utility for obesity management. No significant CIMT changes were observed, indicating long-term vascular adaptation studies are needed