Silveira Ricardo Peterson, de Souza Castro Flávio Antônio, Figueiredo Pedro, Vilas-Boas João Paulo, Zamparo Paola
Int J Sports Physiol Perform. 2017 Jul;12(6):728-735. doi: 10.1123/ijspp.2016-0232. Epub 2016 Oct 13.
To analyze the effects of swimming pace on the relative contribution of leg kick to swimming speed and to compare arm-stroke efficiency (ηF) assessed when swimming with the arms only (SAO) and while swimming front crawl (FCS) using individual and fixed adjustments to arm-stroke and leg-kick contribution to forward speed.
Twenty-nine master swimmers (21 men, 8 women) performed SAO and FCS at 6 self-selected speeds from very slow to maximal. The average swimming speed (v), stroke frequency (SF), and stroke length (SL) were assessed in the central 10 m of the swimming pool. Then, a 2nd-order polynomial regression was used to obtain values of v at paired SF. The percentage difference in v between FCS and SAO, for each paired SF, was used to calculate the relative contributions of the arm stroke (AC) and leg kick (LC) to FCS. Then ηF was calculated using the indirect "paddle-wheel" approach in 3 different ways: using general, individual, and no adjustments to AC.
The LC increased with SF (and speed) from -1% ± 4% to 11% ± 1% (P < .05). At the lower FCS speeds, ηF calculated using general adjustments was lower than ηF calculated using individual adjustments (P < .05), but differences disappear at the fastest speeds. Finally, ηF calculated using individual adjustments to LC in the FCS condition did not differ with ηF assessed in the SAO condition at all the investigated speeds.
The relative contributions of the arm stroke and leg kick should be individually estimated to reduce errors when calculating arm-stroke efficiency at different speeds and in different swimmers.
分析游泳速度对腿部打水在游泳速度中相对贡献的影响，并比较在仅使用手臂游泳（SAO）和自由泳（FCS）时，通过对手臂划水和腿部打水对前进速度的个体和固定调整来评估的手臂划水效率（ηF）。
29名成年游泳运动员（21名男性，8名女性）以6种自定速度（从非常慢到最快）进行SAO和FCS。在游泳池中间10米处评估平均游泳速度（v）、划频（SF）和划幅（SL）。然后，使用二阶多项式回归获得配对SF下的v值。对于每对配对SF，FCS和SAO之间v的百分比差异用于计算手臂划水（AC）和腿部打水（LC）对FCS的相对贡献。然后使用间接“桨轮”方法以3种不同方式计算ηF：使用对AC的一般、个体和无调整。
LC随着SF（和速度）从-1%±4%增加到11%±1%（P<.05）。在较低的FCS速度下，使用一般调整计算的ηF低于使用个体调整计算的ηF（P<.05），但在最快速度下差异消失。最后，在FCS条件下使用对LC的个体调整计算的ηF在所有研究速度下与在SAO条件下评估的ηF没有差异。
在计算不同速度和不同游泳者的手臂划水效率时，应分别估计手臂划水和腿部打水的相对贡献，以减少误差。
