Effect of low-volume interval training on whole-body, abdominal and visceral fat in adults living with overweight and obesity: A systematic review and meta-analysis

This systematic review and meta-analysis examined the impact of low-volume interval training (LV-IT), encompassing both low-volume high-intensity interval training (LV-HIIT) and sprint interval training (SIT), on whole-body, abdominal and visceral fat in adults with overweight and obesity. Fifty-six studies involving 1831 participants were analysed, focusing on outcomes such as whole-body fat mass, body fat percentage, abdominal fat, and visceral fat reduction. LV-IT demonstrated significant reductions in whole-body, abdominal and visceral fat compared to non-exercise control groups (CON), with standardised mean differences (SMD) of -0.62 for whole-body fat mass, -0.85 for body fat percentage, -0.65 for abdominal fat, and -0.90 for visceral fat (all <i>p</i> < 0.001). When compared to moderate-intensity continuous training (MICT), LV-HIIT showed a significantly greater effect in reducing visceral fat (SMD: -0.53, <i>p</i> = 0.01). Notably, no significant differences were observed between LV-IT and high-volume HIIT (HV-HIIT) in fat reduction outcomes. These findings suggest that LV-IT (including LV-HIIT and SIT) may reduce whole-body fat mass, abdominal and visceral fat in adults with overweight and obesity, and the reductions were not different from HV-HIIT. Moreover, LV-HIIT, but not SIT may reduce visceral fat superior to MICT; however, certainty of evidence is low.