Abstract：
In laboratory settings, human locomotion encounters minimal opposition from air resistance. However, moving in nature often requires overcoming airflow. Here, the drag force exerted on the body by different headwind or tailwind speeds (between 0 and 15 m·s-1) was measured during walking at 1.5 m·s-1 and running at 4 m·s-1. To our knowledge, the biomechanical effect of drag in human locomotion has only been evaluated by simulations. Data were collected on eight male subjects using an instrumented treadmill placed in a wind tunnel. From the ground reaction forces, the drag and external work done to overcome wind resistance and to sustain the motion of the center of mass of the body were measured. Drag increased with wind speed: a 15 m·s-1 headwind exerted a drag of ∼60 N in walking and ∼50 N in running. The same tailwind exerted -55 N of drag in both gaits. At this wind speed, the work done to overcome the airflow represented ∼80% of the external work in walking and ∼50% in running. Furthermore, in the presence of fast wind speeds, subjects altered their drag area (CdA) by adapting their posture to limit the increase in air friction. Moving in the wind modified the ratio between positive and negative external work performed. The modifications observed when moving with a head- or tailwind have been compared with moving uphill or downhill. The present findings may have implications for optimizing aerodynamic performance in competitive running, whether in sprints or marathons.NEW & NOTEWORTHY This is the first study to assess the biomechanical adaptations to a wide range of wind speeds inside a wind tunnel. Humans increase their mechanical work and alter their drag area (CdA) by adapting their posture when walking and running against increasing head and tailwinds. The observed drag force applied to the subject is different between walking and running at similar headwind speeds.
摘要：
在实验室环境中，人类运动遇到来自空气阻力的最小阻力。然而,在自然界中移动通常需要克服气流。这里,在1.5ms-1行走和4ms-1跑步期间，测量了由不同的逆风或顺风速度（0-15ms-1）施加在身体上的阻力。据我们所知,阻力在人体运动中的生物力学作用仅通过模拟进行了评估。使用放置在风洞中的仪器跑步机收集了八名男性受试者的数据。从地面反作用力来看，测量了为克服风阻和维持人体质心运动所做的阻力和外部功。阻力随风速增加：15ms-1的逆风在行走中产生〜60N的阻力，在跑步中产生〜50N的阻力。相同的顺风在两个步态中施加了-55N的阻力。在这个风速下,为克服气流所做的工作代表了约80％的步行和约50％的跑步外部工作。此外，在存在快速风速的情况下，受试者通过调整姿势以限制空气摩擦的增加来改变其阻力面积（CdA）。在风中移动修改了执行的正负外部功之间的比率。将顺风或顺风移动时观察到的修改与上坡或下坡移动进行了比较。目前的发现可能对优化竞争运行中的空气动力学性能有影响。无论是短跑还是马拉松。
