Influence of recovery intensity on time spent at maximal oxygen uptake during an intermittent session in young, endurance-trained athletes

Abstract

In this study, we examined the effects of three recovery intensities on time spent at a high percentage of maximal oxygen uptake (t90[Vdot]O2max) during a short intermittent session. Eight endurance-trained male adolescents (16 ± 1 years) performed four field tests until exhaustion: a graded test to determine maximal oxygen uptake ([Vdot]O2max; 57.4 ± 6.1 ml · min−1 · kg−1) and maximal aerobic velocity (17.9 ± 0.4 km · h−1), and three intermittent exercises consisting of repeat 30-s runs at 105% of maximal aerobic velocity alternating with 30 s active recovery at 50% (IE50), 67% (IE67), and 84% (IE84) of maximal aerobic velocity. In absolute values, mean t90[Vdot]O2max was not significantly different between IE50 and IE67, but both values were significantly longer compared with IE84. When expressed in relative values (as a percentage of time to exhaustion), mean t90[Vdot]O2max was significantly higher during IE67 than during IE50. Our results show that both 50% and 67% of maximal aerobic velocity of active recovery induced extensive solicitation of the cardiorespiratory system. Our results suggest that the choice of recovery intensity depends on the exercise objective.