{'fraction_non_alphanumeric': 0.029213483146067417, 'fraction_numerical': 0.017977528089887642, 'mean_word_length': 4.877887788778878, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Physiological responses to different cross country skiing techniques on level terrain.

This study compared the physiological responses and ratings of perceived exertion elicited by several of the most common currently used cross country skiing techniques. The comparison included two classical techniques (kick double pole and diagonal stride), two ski skating techniques (V1 skate and marathon skate), and the double pole technique on both classical and skating skis. Eight male cross country ski racers skied each technique for three laps around a 420 m flat, professionally groomed and tracked oval surface at a mean (+/- SD) velocity of 14.2 +/- 0.6 km.h-1. Heart rate was recorded by telemetry and expired gases were collected for determination of minute ventilation and oxygen consumption during the final minute of each bout. Rating of perceived exertion was requested immediately after each bout. It was found that the diagonal stride technique required the highest oxygen consumption, with the V1 skate, marathon skate, and kick double pole techniques inducing a 16% lower (P less than 0.01) oxygen cost, and the double pole technique inducing a 26% lower (P less than 0.01) oxygen cost. Heart rate was also highest (P less than 0.01) with the diagonal stride technique and lowest with the double pole technique. The rating of perceived exertion was greatest (P less than 0.05) for the diagonal stride technique and lowest (P less than 0.05) for the V1 skate technique. These results indicate that the double pole technique has the greatest economy, the diagonal stride technique elicits the greatest physiological demands and has the highest perceived effort, and the V1 skate technique is associated with the lowest perceived effort under the conditions of this study.