Objective: The goal of this study was to evaluate the influence of high-intensity interval training (HIIT) on anthropometric variables in adults afflicted with overweight or obesity and to compare the effects with those of moderate-intensity continuous training. Methods: A computer literature search was performed for HIIT intervention studies that evaluated anthropometric variables in adults afflicted with overweight or obesity. Results: Of the 857 articles retrieved in the electronic search, 48 met the inclusion criteria. The analyses demonstrated that HIIT was effective in decreasing body mass (-1.45 kg [95% CI: -1.85 to -1.05 kg]), body mass index (-0.44 kg/m² [95% CI: -0.59 to -0.30 kg/m² ]), waist circumference (-2.3 cm [95% CI: -3.1 to -1.4 cm]), waist/hip ratio (-0.01 [95% CI: -0.02 to -0.00]), body fat percentage (-1.29% [95% CI: -1.70% to -0.87%]) and abdominal visceral fat area (-6.83 cm² [95% CI: -11.95 to -1.71 cm² ]). When considering equalization between the two methods (energy expenditure or workload matched), no differences were found in any measure except body mass (for which HIIT was superior). Conclusions: High-intensity interval training and moderate-intensity continuous training results were similar, particularly when equalization between the two methods was considered. Thus, HIIT can be used as a secondary method for the treatment of obesity in adults.