EXCESS POSTEXERCISE OXYGEN CONSUMPTION AFTER HIGH-INTENSITY AND SPRINT INTERVAL EXERCISE, AND CONTINUOUS STEADY-STATE EXERCISE

Higher excess postexercise oxygen consumption (EPOC) after high-intensity interval exercise (HIE) and sprint interval exercise (SIE) may contribute to greater fat loss sometimes reported after interval training compared with continuous steady-state exercise (SSE) training. We compared EPOC after HIE, SIE, and SSE. Ten recreationally active men (age 24 +/- 4 years) participated in this randomized crossover study. On separate days, subjects completed a resting control trial and 3 exercise conditions on a cycle ergometer: HIE (four 4-minute intervals at 95% peak heart rate (HRpeak), separated by 3 minutes of active recovery), SIE (six 30-second-Wingate sprints, separated by 4 minutes of active recovery), and SSE (30 minutes at 80% of HRpeak). Oxygen consumption ((V)over dotO(2)) was measured continuously during and for 3 hours after exercise. For all conditions, (V)over dotO(2) was higher than resting control only during the first hour postexercise. Although 3-hour EPOC and total net exercise energy expenditure (EE) after exercise were higher (p = 0.01) for SIE (22.0 +/- 9.3 L; 110 +/- 47 kcal) compared with SSE (12.8 +/- 8.5 L; 64 +/- 43 kcal), total (exercise + postexercise) net O2 consumed and net EE were greater (p = 0.03) for SSE (69.5 6 18.4 L; 348 +/- 92 kcal) than those for SIE (54.2 +/- 12.0 L; 271 +/- 60 kcal). Corresponding values for HIE were not significantly different from SSE or SIE. Excess postexercise oxygen consumption after SIE and HIE is unlikely to account for the greater fat loss per unit EE associated with SIE and HIE training reported in the literature.