Pre-cooling Decreases Psychophysical Strain During Steadystate Rowing And Enhances Self-paced Performance In Elite Rowers

Abstract

Exercise in hot humid conditions is associated with rising core temperature and adverse psycho-physiological and performance responses. Evidence suggests pre-cooling enhances performance in events lasting several minutes to an hour, but little research exists on short duration events with elite athletes, or the effectiveness of different cooling methods. Purpose To examine the thermoregulatory and psychophysical effects of cooling the torso using an ice (ICE) or water-perfused (WP) vest during rest and a steady-state rowing warm-up on subsequent performance in a 1500 m self-paced ergometer timetrial in the heat. Methods 8 lightweight male rowers (23 ± 4 y) participated in 3 experimental rowing sessions on a Concepts II ergometer in an environmental chamber (38°C, 40% RH) 1 week apart in counterbalanced order. Pre-cooling was applied in 2 of the trials using a VST or WP. In the control condition (CON) the participants wore a WP vest not perfused with water. Vests were worn during a 45 min rest period and 30 min warm up, but removed for a 1500 m time trial. Rectal temperature (Tre), skin temperature (Tsk), heart rate (HR), ratings of perceived exertions (RPE), thermal comfort (TC) and sensation (TS) were monitored throughout the trials. Results There were no significant differences among conditions for HR, Tre, RPE or TS following the warm-up. TC and Tsk were significantly different between CON and both WP and VST following the warm up (P<.05). The reduction in psychophysical strain translated into enhanced time trial performance. This was reflected in a significant increase in power output during the self-paced trial in the VST and WP conditions compared to CON (11±1.2 % and 9.6±1.1% respectively, P>0.05), with the differences evident from the onset of the time-trial (500m). Conclusions Pre-cooling with an ice-vest or water perfused vest enhanced performance in a 1500 m rowing time trial. Rowers chose a higher power output from the onset of the time trial following pre-cooling, consistent with the teleo-anticipation model of fatigue. Supported by NSERC, MSHRF, and PacificSport Canadian Sport Centre Victoria