THE EFFECTS OF INTENSITY OF EXERCISE ON EXCESS POSTEXERCISE OXYGEN-CONSUMPTION AND ENERGY-EXPENDITURE IN MODERATELY TRAINED MEN AND WOMEN

This experiment investigated the effects of intensity of exercise on excess postexercise oxygen consumption (EPOC) in eight trained men and eight women. Three exercise intensities were employed 40%, 50%, and 70% of the predetermined maximal oxygen consumption (VO2max). All ventilation measured was undertaken with a standard, calibrated, open circuit spirometry system. No differences in the 40%, 50% and 70% VO2max trials were observed among resting levels of oxygen consumption (VO2) for either the men or the women. The men had significantly higher resting VO2 values being 0.31 (SEM 0.01) l.min-1 than did the women, 0.26 (SEM 0.01) l.min-1 (P < 0.05). The results indicated that there were highly significant EPOC for both the men and the women during the 3-h postexercise period when compared with resting levels and that these were dependent upon the exercise intensity employed. The duration of EPOC differed between the men and the women but increased with exercise intensity: for the men 40%--31.2 min; 50%--42.1 min; and 70%--47.6 min and for the women, 40%--26.9 min; 50%--35.6 min; and 70%--39.1 min. The highest EPOC, in terms of both time and energy utilised was at 70% VO2max. The regression equation for the men, where y = O2 in litres, and x = exercise intensity as a percentage of maximum was y = 0.380x + 1.9 (r2 = 0.968) and for the women is y = 0.374x - 0.857 (r2 = 0.825).(ABSTRACT TRUNCATED AT 250 WORDS)