School of Human Sciences (Exercise and Sport Science), University of Western Australia, Crawley, Perth, WA, Australia.
Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
Eur J Appl Physiol. 2020 Sep;120(9):2037-2045. doi: 10.1007/s00421-020-04427-0. Epub 2020 Jun 30.
We determined the effect of custom foot orthotics manufactured from ethyl-vinyl acetate (EVA) and expanded thermoplastic polyurethane (TPU) materials, both compared to a control condition (CON; shoes only) during repeated sprints on running mechanical alterations.
Eighteen males performed eight, 5-s sprints with 25-s recovery on an instrumented sprint treadmill in three footwear conditions (EVA, TPU and CON). Mechanical data consisted of continuous (step-by-step) measurement of running kinetics and kinematics, which were averaged for each sprint for further analysis.
Distance ran in 5 s decreased from first to last sprint (P < 0.001), yet with higher sprints 1-8 values for both EVA (P = 0.004) and TPU (P = 0.018) versus CON. Regardless of footwear condition, mean horizontal forces, step frequency, vertical and leg stiffness decreased from sprint 1 to sprint 8 (all P < 0.001). Duration of the propulsive phase was globally shorter for both EVA (P = 0.002) and TPU (P = 0.021) versus CON, while braking phase duration was similar (P = 0.919). In the horizontal direction, peak propulsive (P < 0.001), but not braking (P = 0.172), forces also decreased from sprint 1 to sprint 8, independently of conditions.
Compared to shoe only, wearing EVA or TPU custom foot orthotics improved repeated treadmill sprint ability, yet provided similar fatigue-induced changes in mechanical outcomes.
我们确定了由乙烯-醋酸乙烯酯（EVA）和膨胀热塑性聚氨酯（TPU）材料制造的定制足弓支撑鞋垫在重复短跑过程中对跑步力学变化的影响，与对照条件（仅鞋）进行了比较。
18 名男性在装有仪器的短跑跑步机上进行了三种鞋类条件（EVA、TPU 和 CON）下的 8 次、5 秒冲刺，每次冲刺之间有 25 秒的恢复期。机械数据包括连续（逐步）测量跑步动力学和运动学，为进一步分析对每个冲刺进行平均。
5 秒内的跑步距离从第一冲刺到最后冲刺减少（P<0.001），但在较高的冲刺 1-8 中，EVA（P=0.004）和 TPU（P=0.018）的数值均高于 CON。无论鞋类条件如何，水平力、步频、垂直和腿部刚度的平均值从冲刺 1 到冲刺 8 均下降（所有 P<0.001）。EVA（P=0.002）和 TPU（P=0.021）的推进阶段的持续时间均比 CON 短，而制动阶段的持续时间相似（P=0.919）。在水平方向上，峰值推进力（P<0.001），而不是制动力（P=0.172），也从冲刺 1 到冲刺 8 减少，与条件无关。
与仅穿鞋相比，穿着 EVA 或 TPU 定制足弓支撑鞋垫可提高重复跑步机短跑能力，但在机械结果方面提供了相似的疲劳诱导变化。
