High-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) are essential for managing obesity; however, their efficacy is debated. This network meta-analysis (NMA) compared the effects of HIIT and MICT on body composition and cardiorespiratory fitness in adults with obesity. Related randomized controlled trials were identified by searching the Cochrane Library, PubMed, Web of Science, and Embase databases up to December 5, 2024. Bayesian NMA was performed on studies with intervention durations of 8–16 weeks to evaluate the effects of HIIT (≥ 75 or < 75 min/week) and MICT (≥ 150 or < 150 min/week) on primary outcomes (body weight, body mass index BMI, body fat percentage BFP and maximal oxygen consumption VO₂max) and secondary outcomes (waist-to-hip ratio WHR, waist circumference WC, and hip circumference). Mean differences (MDs) and credible intervals (CrI) were calculated. The surface under the cumulative ranking curve (SUCRA) values were used to rank interventions. The analysis incorporated 18 eligible studies. Compared to the control group, HIIT ≥ 75 min/week was associated with reductions in BFP (MD=-3.05, 95% CrI: -4.69, -1.42), WHR (MD=-0.05, 95% CrI: -0.08, -0.02), and WC (MD=-4.82, 95% CrI: -9.21, -0.46). This regimen ranked first by SUCRA for these outcomes (84.74%, 97.58%, 74.63%, respectively). It also demonstrated the greatest improvement in VO2max (MD = 5.94, 95% CrI: 2.97, 8.88), with a corresponding SUCRA value of 88.68%. Relative to the control group and most other interventions, HIIT ≥ 75 min/week appeared to be associated with greater reductions in BMI and body weight. In conclusion, based on short-term (8–16 weeks) evidence with moderate-to-low certainty, HIIT appears to be a time-efficient option for modest fat loss. HIIT ≥ 75 min/week may be considered for short-term fat loss. MICT ≥ 150 min/week may be an alternative for individuals with low exercise tolerance.
Deng et al. (Sat,) studied this question.