Influence of exercise intensity on time spent at high percentage of maximal oxygen uptake during an intermittent session in young endurance-trained athlete

Abstract

The purpose of this study was to compare, during a 30s intermittent exercise (IE), the effects of exercise intensity on time spent above 90% V˙O2max(t90V˙O2max) and time spent above 95% V˙O2max(t95V˙O2max) in young endurance trained athletes. We hypothesized that during a 30sIE, an increase in exercise intensity would allow an increase in t90V˙O2maxandt95V˙O2max due to a decrease in time to achieve 90% or 95% of V˙O2max. Nine endurance-trained male adolescents took part in three field tests. After determination of their V˙O2max and maximal aerobic velocity (MAV), they performed, until exhaustion, two intermittent exercise sessions alternating 30s at 100% of MAV (IE100) or 110% of MAV (IE110) and 30s at 50% of MAV. Mean time to exhaustion (t lim) values obtained during IE100 were significantly longer than during IE110 (p < 0.01). Moreover, no significant difference was found in t90V˙O2maxort95V˙O2max expressed in absolute or relative (%t lim) values between IE100 and IE110. In conclusion, an increased of 10% of exercise intensity during a 30s intermittent exercise model (with active recovery), does not seem to be the most efficient exercise to solicit oxygen uptake to its highest level in young endurance-trained athletes.