To investigate differences in double-poling (DP) endurance performance, economy, and peak oxygen uptake (V̇O2peak) at low (–15°C) and moderate (6°C) ambient temperatures (TA) in cross-country skiers wearing standard racing suits.
Thirteen well-trained male cross-country skiers performed a standardized warm-up followed by a 5-min submaximal test (Sub1), a 20-min self-paced performance test, a 2nd 5-min submaximal test (Sub2), and an incremental test to exhaustion while DP on an ergometer at either low or moderate TA, randomized on 2 different days. Skin and rectal temperatures, as well as power output and respiratory variables, were measured continuously during all tests.
Skin and rectal temperatures were more reduced at low TA than moderate TA (both P < .05). There was a 5% (P < .05) lower average power output during the 20-min performance test at low TA than at moderate TA, which primarily occurred in the first 8 min of the test (P < .05). Although DP economy decreased from Sub1 to Sub2 for both TAs (both P < .01), a 3.7% (P < .01) larger decrease in DP economy from Sub1 to Sub2 emerged for the low TA. Across the sample, V̇O2peak was independent of TA.
These results demonstrate a lower body temperature and reduced performance for cross-country skiers when DP at low than at moderate TA while wearing standard cross-country-skiing racing suits. Lower DP performance at the low TA was mainly due to lower power production during the first part of the test and coincided with reduced DP economy.
Wiggen and Færevik are with the Dept of Health Research, SINTEF Technology and Society, Trondheim, Norway. Heidelberg and Waagaard are with the Dept of Biology, and Sandbakk, the Dept of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.