Effect Of Prior Warm-up On Oxygen Uptake Kinetics During An 800-m Performance Trial

Abstract

PURPOSE: This study investigated the effect of two different warm-up regimes on pulmonary V[dot]O2 kinetics during an 800-m running time trial. METHODS: Eleven well-trained middle distance runners undertook a laboratory-based progressive exercise test to determine V[dot]O2max, and on two further occasions, an indoor 800-m performance trial. Performance trials were preceded by a 10-min self-paced jog and standardised mobility drills followed by either 6×50m 'strides' (control, CON) or 2×50m strides and a continuous high-intensity 200m run (WU). All warm-up runs were performed at race-pace. Blood lactate was measured before and after the warm-up and performance trial. Oxygen uptake was measured breath-by-breath during all performance trials and subsequently modelled using non-linear regression techniques. The perceived race 'readiness' of the subjects was assessed by questionnaire. RESULTS: Prior to the performance trial, baseline blood [lactate] was (mean ± SD) 1.8 ± 0.3 mM greater after WU compared to CON control (P<0.001). Participants reported significantly greater readiness in WU vs. CON, (P<0.05). The mean response time for the V[dot]O2 response was no different between groups (27.4 ± 6.4 vs 28.0 ± 7.1 s, P = 0.73). Peak V[dot]O2 attained (WU, 4214 ± 848 vs CON, 3913 ± 633 ml.min-1; P=0.156) and total O2 consumed (WU, 119.1 ± 18.2 vs CON, 108.7 ± 27.8 ml.min-1.kg-1, P=0.11) showed tendencies towards a greater response for WU. CONCLUSIONS: These data suggest that a longer duration warm-up promotes readiness for time trial performance. Whilst the mean response time was unaffected by warm-up method, the data suggest a greater contribution from oxidative processes during the performance trial following WU, as indicated by the ∼ 8% greater peak V[dot]O2 attained and total O2 used.