The effects of high-intensity interval training vs. moderate-intensity continuous training on body composition in overweight and obese adults: a systematic review and meta-analysis

ObjectiveThe objective of this study is to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) for improvements in body composition in overweight and obese adults. MethodsTrials comparing HIIT and MICT in overweight or obese participants aged 18-45years were included. Direct measures (e.g. whole-body fat mass) and indirect measures (e.g. waist circumference) were examined. ResultsFrom 1,334 articles initially screened, 13 were included. Studies averaged 10weeksx3 sessions per week training. Both HIIT and MICT elicited significant (p<0.05) reductions in whole-body fat mass and waist circumference. There were no significant differences between HIIT and MICT for any body composition measure, but HIIT required similar to 40% less training time commitment. Running training displayed large effects on whole-body fat mass for both HIIT and MICT (standardized mean difference -0.82 and -0.85, respectively), but cycling training did not induce fat loss. ConclusionsShort-term moderate-intensity to high-intensity exercise training can induce modest body composition improvements in overweight and obese individuals without accompanying body-weight changes. HIIT and MICT show similar effectiveness across all body composition measures suggesting that HIIT may be a time-efficient component of weight management programs.