Effects Of Short-Lasting Supramaximal-Intensity Exercise On Diet-Induced Increase In Oxygen Uptake

This study was undertaken to quantify the additional increase in diet-induced oxygen uptake after exhaustive high-intensity intermittent exercise (HIIE), consisting of 6-7 bouts of 20-sec bicycle exercise (intensity: 170% VO2max) with a 10-sec rest between bouts. Using a metabolic chamber, the oxygen uptake of ten men was measured from 10:30 AM to 07:00 AM the next day on two separate days with or without HIIE, with lunch (12:00) and supper (18: 00) (Diet experiment). On two other days, the oxygen uptake of six different subjects was measured from 10: 30 to 16: 00 with or without HIIE, but without meals (Fasting experiment). Ten minutes of exercise at 50% VO2max preceded the HIIE in both experiments; EPOC (excess postexercise oxygen consumption) after HIIE was found to wear off before 12: 00 in both experiments. In the Diet experiment, oxygen uptake during HIIE and EPOC were 123.4 +/- 12.0 and 115.3 +/- 32.3 mL.kg(-1), respectively. Meals elevated resting oxygen uptake on both days, but those on the HIIE day were significantly higher than on the control day. This enhanced diet-induced oxygen uptake (difference in resting oxygen uptake from 12:00-23:00 between HIIE and control day: Delta DIT) was 146.1 +/- 90.9 mL.kg(-1), comparable to the oxygen uptake during the HIIE and EPOC. The Delta DIT was correlated with subjects' VO2max (52.1 +/- 6.6 mL.kg(-1).min(-1)) (r = 0.76, n = 10, P < 0.05). We concluded that HIIE enhances diet-induced oxygen uptake significantly, and that it is related to the cardiorespiratory fitness.