The effect of prior exercise intensity on oxygen uptake kinetics during high-intensity running exercise in trained subjects

Purpose The aim of this study was to compare the effects of two different kinds of prior exercise protocols [continuous exercise (CE) versus intermittent repeated sprint (IRS)] on oxygen uptake ( V O 2 ) kinetics parameters during high-intensity running. Methods Thirteen male amateur futsal players (age 22.8 ± 6.1 years; mass 76.0 ± 10.2 kg; height 178.7 ± 6.6 cm; V O 2max 58.1 ± 4.5 mL kg −1 min −1 ) performed a maximal incremental running test for the determination of the gas exchange threshold (GET) and maximal V O 2 ( V O 2max ). On two different days, the subjects completed a 6-min bout of high-intensity running (50 % ∆) on a treadmill that was 6-min after (1) an identical bout of high-intensity exercise (from control to CE), and (2) a protocol of IRS (6 × 40 m). Result We found significant differences between CE and IRS for the blood lactate concentration ([La]; 6.1 versus 10.7 mmol L −1 , respectively), V O 2 baseline (0.74 versus 0.93 L min −1 , respectively) and the heart rate (HR; 102 versus 124 bpm, respectively) before the onset of high-intensity exercise. However, both prior CE and prior IRS significantly increased the absolute primary V O 2 amplitude (3.77 and 3.79 L min −1 , respectively, versus control 3.54 L min −1 ), reduced the amplitude of the V O 2 slow component (0.26 and 0.21 L min −1 , respectively, versus control 0.50 L min −1 ), and decreased the mean response time (MRT; 28.9 and 28.0 s, respectively, versus control 36.9 s) during subsequent bouts. Conclusion This study showed that different protocols and intensities of prior exercise trigger similar effects on V O 2 kinetics during high-intensity running.