• Systematic review of the efficacy of high intensity interval training versus continuous training for weight loss in overweight and obese individuals

      Fallows, Stephen; O'Keeffe, Chris (University of Chester, 2015-09)
      The increasing prevalence of individuals being overweight and obese in conjunction with the associated co-morbidities continues to be a major public health concern. The traditional exercise prescription to accomplish weight loss in such a population has been to perform sustained low to moderate intensity aerobic exercise termed “continuous (CONT) training.” More recently high intensity interval training (HIIT) has been suggested as a more effective alternative for weight loss. HIIT involves short periods of high intensity efforts interspersed with recovery periods of lower intensity. The rationale for such an approach is that individuals can achieve similar results to longer CONT type training but in less time. The purpose of this systematic review is to compare the effects of HIIT and CONT training on weight loss and other anthropometric measures in overweight and obese adults when both training protocols are matched for energy expenditure. A total of nine studies met the selection criteria for inclusion in the review. Four studies included only overweight participants. Of these four, one showed that both CONT training and HIIT were similarly effective for reducing body mass, BMI, body fat, FFM and waist circumference, whilst one concluded that CONT training rather than HIIT was more effective at reducing total body fat and android fat. The remaining two found neither CONT nor HIIT to be effective at reducing overall body mass. Three studies used only obese participants. One found both CONT and HIIT to be equally effective in reducing measures of body mass, BMI and body fat. One found CONT training and HIIT were both equally effective in reducing body mass, fat mass, and gynoid fat mass when combined with a strict calorie controlled diet. The third found neither exercise protocol to be successful for weight or regional fat loss despite the inclusion of dietary guidance as part of the intervention. Of the two studies that included both overweight and obese participants one revealed that both CONT training and HIIT were equally effective in favourably altering body mass, BMI and waist circumference whilst the second showed that both protocols were equally effective at reducing body fat and waist circumference. This review does not support the premise that HIIT is superior to CONT training for weight and fat loss in overweight and obese adults when both exercise protocols are isocalorific in terms of energy expended. Rather, both approaches appear to be similarly effective for inducing favourable anthropometric changes and a combination of the two may be considered as a means to achieving weight loss in overweight and obese adults based on individual preference.