Aspects on muscle properties and use in competitive Alpine skiing.
This brief report describes the physiological demands in competitive Alpine skiing as well as the physiological profile of elite skiers. Maximal heart rate is typically attained by the end of either of the four Alpine ski disciplines. The giant slalom probably calls for the largest reliance upon aerobic energy metabolism and oxygen uptake may increase to 75%-100% of maximal aerobic power. Although high caliber skiers typically show increased maximal aerobic power, it is unlikely that this is an important factor determining success in skiing. Also, anaerobic energy provision accounts for more than half of the total energy yield. Accordingly, plasma and muscle lactate accumulation is substantial after a single race. Similarly, during skiing there is a high rate of glycogen utilization that eventually may result in depletion of muscle glycogen stores by the end of a day of intense skiing. Muscles of Alpine skiers do not possess a distinct fiber type composition and, if anything, skiers tend to show a preponderance of slow twitch fibers. This concords with the recruitment of both muscle fiber types during slalom or giant slalom. Elite skiers show increased knee extensor strength. This seems warranted because there is great reliance upon slow and forceful eccentric muscle actions when performing turns in the giant slalom or slalom.
Tesch
P A
PA
Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden.
D004734:Energy Metabolism / Q000502:physiology; D006003:Glycogen / Q000378:metabolism; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007773:Lactates / Q000097:blood / Q000378:metabolism; D018485:Muscle Fibers, Skeletal / Q000502:physiology / Q000648:ultrastructure; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology; D012865:Skiing / Q000145:classification / Q000502:physiology*
D007773:Lactates; D006003:Glycogen