Excess Postexercise Oxygen Consumption and Fat Utilization Following Submaximal Continuous and Supramaximal Interval Running

Abstract

ABSTRACTPurpose: Few studies have directly compared excess postexercise oxygen consumption (EPOC) and fat utilization following different exercise intensities, and the effect of continuous exercise exceeding 75% of maximal oxygen uptake (VO2max) on these parameters remains unexplored. The current study examined EPOC and fat utilization following acute moderate- and vigorous-intensity continuous training (MICT and VICT) and sprint interval training (SIT). Methods: Eight active young men performed 4 experimental sessions: (a) MICT (30 min of running at 65% VO2max); (b) VICT (30 min of running at 85% VO2max); (c) SIT (4 30-s “all-out” sprints with 4 min of rest); and (d) no exercise (REST). Excess postexercise oxygen consumption and fat oxidation were estimated from gas measurements (VO2 and carbon dioxide production [VCO2]) obtained during a 2-hr postexercise period. Results: Total EPOC was similar (p = .097; effect size [ES] = 0.3) after VICT (8.6 ± 4.7 L) and SIT (10.0 ± 4.2 L) and greater after both (VICT, p = .025, ES = 0.3, and SIT, p < .001, ES = 0.6) versus MICT (6.0 ± 4.3 L). Fat utilization increased after MICT (0.047 ± 0.018 g· min−1, p = .018, ES = 1.3), VICT (0.066 ± 0.020 g•min−1, p = .034, ES = 2.2), and SIT (0.115 ± 0.026 g•min−1, p < .001, ES = 4.0) versus REST (0.025 ± 0.018 g•min−1) and was greatest after SIT (p < .001, ES = 3.0 vs. MICT; p = .031, ES = 2.1 vs. VICT). Conclusion: Acute exercise increases EPOC and fat utilization in an intensity-dependent manner.