Centre for Elite Sports Research, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.
PLoS One. 2020 Jul 15;15(7):e0236102. doi: 10.1371/journal.pone.0236102. eCollection 2020.
Cross-country skiers use different sub-techniques like 'gears' (diagonals stride, double poling with kick, and double poling) depending on terrain (incline) and demand (speed and external work rate). Previous studies have identified the major effect of speed and incline, but not any potential interaction between these parameters: the incline-speed combination determines the work rate, which in itself may be a controlling factor. The aim of this study was to investigate the role of these task conditions (external work rate, speed, incline) and their interactions on the choice of sub-technique in classical roller skiing. Twelve male and nine female cross-country skiers executed three subsets of protocols in which two of three condition parameters were altered every 15 seconds while roller skiing on a treadmill. This design created a quasi-random set of combinations of speed, incline and work rate that were analysed on sub-technique choice. A repeated measures model with sex as between subject factor was conducted for each subset of protocols. The incline appeared to be the factor affecting sub-technique choice most, but not exclusively; at constant incline, athletes applied different sub-techniques, depending mostly on speed rather than work rate. Most athletes did not use one particular sub-technique for a given speed-incline-work rate combination, but it depended on the protocol and direction of condition change in the constant speed protocol (hysteresis). Only minor differences between men and women existed regarding the impact of condition factor on sub-technique choice. The findings disagree with the notion of a simple mechanism that explains the choice of sub-technique, but rather opt for a complex structure that entangles various mechanisms which play a role in the choice of sub-technique under moderate effort conditions.
越野滑雪者根据地形（坡度）和需求（速度和外部功量率）使用不同的亚技术，如“齿轮”（对角线步幅、双杆踢腿和双杆）。以前的研究已经确定了速度和坡度的主要影响，但没有任何关于这些参数之间潜在相互作用的研究：坡度-速度组合决定了功量率，而功量率本身可能是一个控制因素。本研究的目的是探讨这些任务条件（外部功量率、速度、坡度）及其相互作用在经典滚轴滑雪中对亚技术选择的作用。12 名男性和 9 名女性越野滑雪运动员在跑步机上进行了三组实验，每组实验中每隔 15 秒改变三个条件参数中的两个，以模拟三种不同的实验条件。这种设计创造了一种速度、坡度和功量率的准随机组合，用于分析亚技术选择。对于每个协议子集，都使用性别作为组间因素进行了重复测量模型分析。结果表明，坡度似乎是影响亚技术选择的最重要因素，但不是唯一因素；在恒定坡度下，运动员会根据速度而不是功量率选择不同的亚技术。大多数运动员不会为给定的速度-坡度-功量率组合选择一种特定的亚技术，但这取决于协议和恒定速度协议中条件变化的方向（滞后）。男性和女性在条件因素对亚技术选择的影响方面几乎没有差异。这些发现与简单机制解释亚技术选择的观点不一致，而是倾向于一种复杂的结构，这种结构交织了各种在适度努力条件下选择亚技术的机制。
