der Meulen Lennert Van, Bonnaerens Senne, Caekenberghe Ine Van, Clercq Dirk De, Segers Veerle, Fiers Pieter
Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium.
Department of Movement and Sports Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
J Hum Kinet. 2024 Sep 26;94:37-45. doi: 10.5114/jhk/191528. eCollection 2024 Oct.
Running style is temporally defined by a duty factor and stride frequency and believed to be related to the loading experienced during ever step. However, the exact relationship between both temporal variables and loading magnitude is still unknown. We aimed to identify the relationship between a duty factor and stride frequency with external load measures, joint reaction forces and joint moments. Thirty-one healthy female recreational runners ran across a 25-m runway at a speed of 2.30 ± 0.05 m·s. Ground reaction forces and motion capture data were used to determine the maximal vertical ground reaction force, the vertical instantaneous loading rate, peak braking force, peak joint extension moments and peak joint reaction forces at the knee and the ankle. The habitual duty factor and stride frequency of runners did not correlate with each other. The duty factor was found to be a significant predictor of maximal vertical ground reaction force (R = 0.585), peak braking force (R = 0.153), peak knee extension moment (R = 0.149), ankle plantar flexion moment (R = 0.225) and peak joint reaction forces at the knee (R = 0.591) and the ankle (R = 0.592), but not of the vertical instantaneous loading rate. Stride frequency had no significant predictive value. In conclusion, the maximal loading and potential injury risk of female recreational runners running with high duty factors are lower compared to those of peers running with lower duty factors.
跑步方式在时间上由负荷系数和步频定义，并且被认为与每一步中所承受的负荷有关。然而，这两个时间变量与负荷大小之间的确切关系仍然未知。我们旨在确定负荷系数和步频与外部负荷测量值、关节反应力和关节力矩之间的关系。31名健康的女性业余跑步者以2.30±0.05米·秒的速度跑过一条25米的跑道。地面反作用力和运动捕捉数据被用于确定最大垂直地面反作用力、垂直瞬时负荷率、峰值制动力、膝关节和踝关节的峰值关节伸展力矩以及峰值关节反应力。跑步者的习惯负荷系数和步频彼此不相关。负荷系数被发现是最大垂直地面反作用力（R = 0.585）、峰值制动力（R = 0.153）、峰值膝关节伸展力矩（R = 0.149）、踝关节跖屈力矩（R = 0.225）以及膝关节（R = 0.591）和踝关节（R = 0.592）的峰值关节反应力的显著预测指标，但不是垂直瞬时负荷率的预测指标。步频没有显著的预测价值。总之，与负荷系数较低的同龄人相比，负荷系数较高的女性业余跑步者的最大负荷和潜在受伤风险更低。
