Tolerance to high-intensity intermittent running exercise: do oxygen uptake kinetics really matter?

We examined the respective associations between aerobic fitness (max), metabolic control ( kinetics) and locomotor function, and various physiological responses to high-intensity intermittent (HIT) running exercise in team sport players. Eleven players (30.5 ± 3.6 year) performed a series of tests to determine their max and the associated velocity (vmax), maximal sprinting speed (MSS) and kinetics at exercise onset in the moderate and severe intensity domains, and during recovery ( SEV). Cardiorespiratory variables, oxygenation and electromyography of lower limbs muscles and blood lactate ([La]) concentration were collected during a standardized HIT protocol consisting in 8 sets of 10, 4-s runs. During HIT, four players could not complete more than two sets; the others finished at least five sets. Metabolic responses to the two first sets of HIT were negatively correlated with max, vmax, and SEV (r = −0.6 to −0.8), while there was no clear relationship with the other variables. , oxygenation and [La] responses to the first two sets of HIT were the only variables that differed between the players which could complete at least five sets or those who could not complete more than two sets. Players that managed to run at least five sets presented, in comparison with the others, greater vmax [ES = +1.5(0.4; 2.7), MSS(ES = +1.0(0.1; 1.9)] and training load [ES = +3.8 (2.8; 4.9)]. There was no clear between-group difference in any of the kinetics measures [e.g., ES = −0.1(−1.4; 1.2) for SEV]. While max and vmax are likely determinant for HIT tolerance, the importance of kinetics as assessed in this study appears limited in the present population. Knowing the main factors influencing tolerance to HIT running exercise may assist practitioners in personalizing training interventions.

This study examines the relationship between oxygen uptake kinetics and tolerance to high-intensity intermittent running.