a Faculty of Kinesiology , University of Calgary , Calgary , Canada.
b Department of Health and Physical Education , Mount Royal University , Calgary , Canada.
J Sports Sci. 2019 Jul;37(13):1457-1463. doi: 10.1080/02640414.2019.1565650. Epub 2019 Jan 18.
Altering torsional stiffness of cycling shoe soles may be a novel approach to reducing knee joint moments and overuse injuries during cycling. We set out to determine if the magnitude of three-dimensional knee moments were different between cycling shoe soles with different torsional stiffnesses. Eight trained male cyclists cycled at 90% lactate threshold power output in one of two cycling shoe conditions in a randomized crossover design. The shoe sole was considered torsionally flexible (FLEX) compared to a relatively stiffer (STIFF) sole. Gross efficiency (GE) and knee joint moments were quantified. No significant effect of shoe condition was seen in GE (21.4 ± 1.1% and 20.9 ± 1.6% for FLEX and STIFF, respectively, = 0.12), nor in three-dimensional knee moments. 4 of the 8 subjects had reduced knee moments in at least 2 of the 3 moment directions. These "responders" were significantly shorter (1.73 ± 0.02 m vs 1.81 ± 0.04 m, = 0.017) and had a higher relative maximal aerobic power (MAP) (4.6 ± 0.3 W∙kg-1 vs 3.9 ± 0.3 W∙kg-1, = 0.024) compared to non-responders. These results suggest that certain shoe characteristics may influence certain individuals differently because these participants belong to different "functional groups"; certain individuals may respond positively to FLEX, while others may not. Further studies should test this proposed hypothesis.
改变自行车鞋底的扭转刚度可能是一种减少骑车时膝关节力矩和过度使用损伤的新方法。我们旨在确定不同扭转刚度的自行车鞋底之间三维膝关节力矩是否存在差异。8 名经过训练的男性自行车运动员以 90%的乳酸阈功率输出在两种自行车鞋条件中的一种下进行随机交叉设计的骑行。与相对较硬（STIFF）鞋底相比，鞋底被认为具有扭转灵活性（FLEX）。定量测量总效率（GE）和膝关节力矩。在 GE 方面，鞋条件没有显著影响（FLEX 和 STIFF 分别为 21.4±1.1%和 20.9±1.6%， = 0.12），三维膝关节力矩也没有显著影响。8 名受试者中有 4 名在至少 3 个力矩方向中的 2 个方向上的膝关节力矩减小。这些“响应者”明显更矮（1.73±0.02 m 比 1.81±0.04 m， = 0.017），并且相对最大有氧功率（MAP）更高（4.6±0.3 W∙kg-1 比 3.9±0.3 W∙kg-1， = 0.024）比非响应者。这些结果表明，某些鞋的特性可能会因个体的不同而对某些人产生不同的影响，因为这些参与者属于不同的“功能组”；某些人可能对 FLEX 有积极的反应，而其他人则可能没有。进一步的研究应该测试这一假设。
