title: Net efficiency of roller skiing with a diagonal stride.
abstract: The aims of this study were: (a) to determine net efficiency during roller skiing with a diagonal stride at various speeds; (b) to assess the development of net efficiency across speeds; and (c) to examine the characteristics of efficiency in diagonal roller skiing. Two-dimensional kinematics and oxygen uptake were determined in eight male collegiate cross-country ski athletes who roller skied with the diagonal stride at various speeds on a level track. Net efficiency was calculated from rates of internal and external work and net energy expenditure. Individual net efficiency ranged from 17.7% to 52.1%. Net efficiency in the entire group of athletes increased with increasing speed, reached a maximum value of 37.3% at 3.68 m · s(-1), before slowly decreasing. These findings indicate that roller skiing with the diagonal stride at high speed is a highly efficient movement and that an optimal speed exists at which net efficiency can be maximally enhanced in diagonal roller skiing.
authors.affiliation: Graduate School of Sport and Exercise Science, Osaka University of Health and Sport Sciences, Osaka, Japan. minaharus@nike.eonet.ne.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Nakai
authors.forename: Akira
authors.initials: A
authors.lastname: Ito
mesh_terms: D000293:Adolescent; D000328:Adult; D056352:Athletes; D001696:Biomechanical Phenomena; D004734:Energy Metabolism; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D010101:Oxygen Consumption; D005082:Physical Exertion; D012865:Skiing / Q000502:physiology*; D055815:Young Adult