Oxygen uptake during recovery from intense intermittent running and prolonged walking.

The purpose of this study was to compare recovery energy expenditure following three exercise conditions varying widely in intensity and duration. Subjects were five well-trained female distance runners whose mean age and VO2 max +/- 1 SD were 22.4 +/- 1.6 yr and 61.8 +/- 7.3 ml/kg-1/min-1, respectively. Exercise sessions consisted of walking for 2 h at 24.5% of VO2max, running continuously for 10 min at 81.1% of VO2max, and exercising intermittently with 2 min runs at 89.2% VO2max alternated with 2 min walks at 93.8 m/min-1. VO2 was determined continuously with open circuit spirometry during 1 h of exercise recovery. Total recovery VO2 (L) was taken as the sum of the 60 1-minute values. After walking, VO2 reached baseline values at 40 min of recovery while VO2 remained elevated at 1 h for both the continuous and intermittent exercise. The total VO2 (L) in recovery was significantly greater (p < 0.05) for both continuous (19.09 +/- 1.2 VO2) and intermittent (22.4 +/- 1.5 L) running than walking (17.4 +/- 0.7 L) and intermittent exercise recovery VO2 was significantly greater than for continuous running (p < 0.05). It was concluded that high intensity exercise, either intermittent or continuous, increases recovery VO2 (L) more than prolonged low intensity exercise. Furthermore, the total exercise VO2 explains a large portion of the variance in recovery VO2.