Toussaint H M, Janssen T, Kluft M
Department of Health Sciences, Faculty of Human Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
J Biomech. 1991;24(3-4):205-11. doi: 10.1016/0021-9290(91)90178-p.
In swimming the propulsive force is generated by giving a velocity change to masses of water. In this process energy is transferred from the swimmer to the water, which cannot be used to propel the swimmer. Theoretical considerations indicated that an increase of the propelling surface size should lead to a reduced loss of energy to the water. Thus, in this study, the effect of artificially enlarging the propelling surface of the hand was examined. The effect was examined in terms of the propelling efficiency during front crawl swimming using the arms alone. The legs were floated with a small buoy as previously described (Toussaint et al., J. appl. Physiol. 65, 2506-2512, 1988a). In ten competitive swimmers (six male, four female) the rate of energy expenditure (power input, Pi), power output (Po), work per stroke cycle (As), distance per stroke cycle (d), work per unit distance (Ad), and propelling efficiency (ep) were determined at various swimming speeds once with and once swimming without paddles. At the same average velocity the effect of swimming with paddles was to reduce Pi, Po, and Ad by 6, 7.6, and 7.5% respectively, but to increase ep and As by 7.8 and 7%. The increase in distance per stroke cycle and the decrease in stroke cycle frequency matched the predicted values based on the theoretical considerations in which the actual increase in propelling surface size was taken into account.
在游泳时，推进力是通过改变一定质量的水的速度而产生的。在这个过程中，能量从游泳者传递到水中，而这部分能量无法用于推动游泳者前进。理论分析表明，增大推进面的尺寸应该会减少向水中散失的能量。因此，在本研究中，我们考察了人为增大手部推进面的效果。该效果通过仅使用手臂进行自由泳时的推进效率来评估。如前所述（图桑等人，《应用生理学杂志》65卷，2506 - 2512页，1988年a期），用一个小浮标使腿部漂浮起来。在10名竞技游泳运动员（6名男性，4名女性）中，分别测定了他们在有划水板和无划水板游泳时，不同游泳速度下的能量消耗率（功率输入，Pi）、功率输出（Po）、每个划水周期的功（As）、每个划水周期的距离（d）、单位距离的功（Ad）以及推进效率（ep）。在相同的平均速度下，使用划水板游泳的效果是使Pi、Po和Ad分别降低了6%、7.6%和7.5%，但使ep和As分别提高了7.8%和7%。每个划水周期距离的增加和划水周期频率的降低与基于理论分析并考虑了推进面实际增大情况所预测的值相符。
