Comparison of energy expenditure elevations after submaximal and supramaximal running.

Although exercise intensity has been identified as a major determinant of the excess postexercise oxygen consumption (EPOC), no studies have compared the EPOC after submaximal continuous running and supramaximal interval running. Eight male middle-distance runners [age = 2.1 +/- 3.1 (SD) yr; mass = 67.8 +/- 5.1 kg; maximal oxygen consumption (VO2max) = 69.2 +/- 4.0 ml.kg-1.min-1] therefore completed two equated treatments of treadmill running (continuous running: 30 min at 70% VO2max; interval running: 20 x 1-min intervals at 105% VO2max with intervening 2-min rest periods) and a control session (no exercise) in a counter-balanced research design. The 9-h EPOC values were 6.9 +/- 3.8 and 15.0 +/- 3.3 liters (t-test:P = 0.001) for the submaximal and supramaximal treatments, respectively. These values represent 7.1 and 13.8% of the net total oxygen cost of both treatments. Notwithstanding the higher EPOC for supramaximal interval running compared with submaximal continuous running, the major contribution of both to weight loss is therefore via the energy expended during the actual exercise.