The literature suggests that precooling can increase exercise performance in a warm ambient. In particular, this is true for cycling and running performance (1, 2). However, it is unclear how precooling affects swimming performance. The present study aimed to investigate the effect of precooling on 1500 m swimming performance. Methods Eight subjects, 4 female and 4 male triathletes, participated in the study. Their average ± SD age was 29 ± 6 yr., height 173 ± 11 cm, weight 69.3 ± 12.1 kg and VO2peak 60.2 ± 6.3 ml•min-1•kg-1. Control (CON) and precooling (COOL) trials were performed on the same time of a day, at least one week apart. Both trials consisted out of: i)10 min warm-up at 40% of subject`s VO2peak on a cycle-ergometer, followed by ii) 1500 m swimming at competition speed in water with the temperature of 27.6 ± 0.1 °C. In addition, during COOL trial subjects wore an ice vest (Arctic Heat, Burleigh Heads, QLD, Australia) 35 min preceding the warm-up and during the warm-up. During the trials, gastrointestinal temperature (Tc) and skin temperature on four body locations (Tsk) were continually registered. In addition, the subjects were asked to rate their thermal perception (TP) prior the warm-up and post swimming. Finally, the time for swimming 1500 m was noted. Results The effect of precooling was reflected in a significant 0.17 ± 0.18 ºC decrease (p=0.045) in Tc and a 0.79 ± 0.33 ºC decrease in Tsk (p=0.001). Lower Tc, observed for COOL trial, persisted till the end of swimming. In particular, Tc at the end of swimming was 37.89 ± 0.34 ºC in COOL and 38.31 ± 0.34 ºC in CON (p=0.049). In contrast, Tsk was not significantly different at the end of swimming among the trials. Prior to swimming, subjects rated TP in CON and COOL as slightly warm (1 ± 1) and cool (-2 ± 1; p=0.015), respectively. Likewise, at the end of swimming, subjects rated TP in CON trial as hot (3 ± 1), while in COOL trial as warm (2 ± 1; p=0.021). The swimming performance was with 22:29 ± 2:00 min significantly shorter in COOL trial compared to 23:04 ± 2:02 min observed for CON trial (p=0.014). Conclusion The observed results suggest that precooling with an ice vest, prior and during the warm-up significantly decreases Tc. Since lower Tc persisted through swimming it is suggested that this effect enables subjects to improve swimming performance. References 1.Marino FE. Methods, advantages, and limitations of body cooling for exercise performance. Br J Sports Med 36: 89-94, 2002. 2.Quod MJ, Martin DT, and Laursen PB. Cooling athletes before competition in the heat: comparison of techniques and practical considerations. Sports Med 36: 671-682, 2006.
© Copyright 2009 14th annual Congress of the European College of Sport Science, Oslo/Norway, June 24-27, 2009, Book of Abstracts. Veröffentlicht von The Norwegian School of Sport Sciences. Alle Rechte vorbehalten.