van der Woude L H, Bakker W H, Elkhuizen J W, Veeger H E, Gwinn T
Faculty of Human Movement Sciences, Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
Am J Phys Med Rehabil. 1998 May-Jun;77(3):222-34. doi: 10.1097/00002060-199805000-00007.
Wheelchair sports and daily manual wheelchair propulsion are dominated by frequent short-term power demands. The purpose of the current cross-sectional study was to determine the variation in propulsion technique in association with sprint power production among elite wheelchair athletes. Therefore, 67 wheelchair athletes (different impairments; 17 female and 50 male athletes; age, 29.1+/-7 yr; body weight, 60.7+/-11.8 kg; training hours, 12.9+/-6.4 h x wk(-1); VO2 peak, 1.7+/-0.7 liter x min(-1); aerobic power output, 72.2+/-36.7 W) were studied during the World Championships and Games for the Disabled in Assen (1990) on propulsion technique and anaerobic work capacity in a 30-s sprint test on a computer controlled wheelchair ergometer. Mean power output (P30) (97+/-45.8 W; range, 8.3-195.3 W) and heart rate (158.6+/-23.6 b x min(-1)) were highly variable and seemed associated with impairment level: track athletes, classified in four different functional classes, showed a class-related P30 of 23, 68, 100, and 138 W for the male athletes (n=38). Sprint power relative to body weight varied between 0.36 W X kg BW(-1)+/-0.04 and 1.85 W X kg BW(-1)+/-0.43 for the different subject groups. Propulsion technique in terms of forces applied to the rim and timing showed significant differences between subject groups for the majority of parameters studied. Apart from the mediolateral force and the negative dip at the start of the push phase, the technique parameters were significantly related to power production. Fraction effective force, the ratio between the total force vector and the effective force applied to the hand rim, appeared low on average (especially for subjects with cerebral palsy and those with a high spinal lesion) but showed a significant correlation with power output (r=0.5). In general, propulsion technique parameters were related to both performance and functionality. The number of training hours showed a small but significant relation with peak power (r=0.31), peak torque (r=0.4), the amount of work per push (r=0.41) and the total force vector (r=0.31), stressing the role of training status, next to disability, as important mediating factor in both propulsion technique as well as performance capacity. No association between training hours and fraction effective force was seen. It can be concluded that propulsion technique and performance parameters are highly variable among wheelchair athletes. Also, propulsion technique is strongly associated with functionality and training hours and does clearly relate to performance. The current results on technique and performance and their possible causal relationship, but also with impairment and sports discipline, must be further substantiated in a longitudinal study design.
轮椅运动和日常手动轮椅推进主要由频繁的短期功率需求主导。当前这项横断面研究的目的是确定精英轮椅运动员的推进技术与冲刺功率产生之间的变化关系。因此，在阿森（1990年）举行的世界残疾人锦标赛和运动会期间，对67名轮椅运动员（不同损伤类型；17名女性和50名男性运动员；年龄，29.1±7岁；体重，60.7±11.8千克；训练时长，12.9±6.4小时/周；最大摄氧量，1.7±0.7升/分钟；有氧功率输出，72.2±36.7瓦）在计算机控制的轮椅测力计上进行的30秒冲刺测试中的推进技术和无氧工作能力进行了研究。平均功率输出（P30）（97±45.8瓦；范围，8.3 - 195.3瓦）和心率（158.6±23.6次/分钟）变化很大，且似乎与损伤程度有关：分为四个不同功能级别的田径运动员，男性运动员（n = 38）的P30与级别相关，分别为23瓦、68瓦、100瓦和138瓦。不同受试者组的冲刺功率相对于体重在0.36瓦/千克体重±0.04至1.85瓦/千克体重±0.43之间变化。就施加在轮辋上的力和时间而言，推进技术在大多数研究参数上受试者组之间存在显著差异。除了外侧力和推阶段开始时的负倾角外，技术参数与功率产生显著相关。有效力分数，即总力矢量与施加在手轮辋上的有效力之比，平均看来较低（尤其是对于脑瘫患者和高位脊髓损伤患者），但与功率输出显示出显著相关性（r = 0.5）。总体而言，推进技术参数与表现和功能都相关。训练时长与最大功率（r = 0.31）、最大扭矩（r = 0.4）、每次推的工作量（r = 0.41）和总力矢量（r = 0.31）显示出小但显著的关系，强调了训练状态除残疾外作为推进技术以及表现能力中重要中介因素的作用。未观察到训练时长与有效力分数之间的关联。可以得出结论，轮椅运动员的推进技术和表现参数变化很大。此外，推进技术与功能和训练时长密切相关，且显然与表现有关。关于技术和表现及其可能的因果关系，以及与损伤和运动项目的当前结果，必须在纵向研究设计中进一步证实。
