Effect of ambient temperature on endurance performance while wearing cross-country skiing clothing

This study assessed the effects of exposure to cold (−14 and −9 °C), cool (−4 and 1 °C) and moderate warm (10 and 20 °C) environments on aerobic endurance performance-related variables: maximal oxygen consumption (VO_2max), running time to exhaustion (TTE), running economy and running speed at lactate threshold (LT). Nine male endurance athletes wearing cross-country ski racing suit performed a standard running test at six ambient temperatures in a climatic chamber with a wind speed of 5 m s⁻¹. The exercise protocol consisted of a 10-min warm-up period followed by four submaximal periods of 5 min at increasing intensities between 67 and 91 % of VO_2max and finally a maximal test to exhaustion. During the time course mean skin temperature decreased significantly with reduced ambient temperatures whereas T _re increased during all conditions. T _re was lower at −14 °C than at −9 and 20 °C. Running economy was significantly reduced in warm compared to cool environments and was also reduced at 20 °C compared to −9 °C. Running speed at LT was significantly higher at −4 °C than at −9, 10 and 20 °C. TTE was significantly longer at −4 and 1 °C than at −14, 10 and 20 °C. No significant differences in VO_2max were found between the various ambient conditions. The optimal aerobic endurance performance wearing a cross-country ski racing suit was found to be −4 and 1 °C, while performance was reduced under moderate warm (10 and 20 °C) and cold (−14 and −9 °C) ambient conditions.