This study investigated how different shapes of umbrella handles and grip types influence muscle activation and postural variability under windy conditions. Seventeen adult participants were enrolled in this study, and different handle shapes (cylindrical, ellipsoidal, and triangular prism-shaped), grip types (four- and five-finger grip), and wind strengths were tested. Activation of the forearm and upper arm muscles was recorded using surface electromyography. Postural variability and ratings of (1) perceived difficulty of use and (2) perceived grip-posture variability were measured. The results indicated that activation of the finger flexor muscle increased under windy conditions, whereas postural variability was not affected. Weak wind (3.2–7.5 m/s) conditions caused greater perceived postural variability and activation of the wrist extensor muscle. The ellipsoidal handle shape had lower endpoint postural variability when held with a five-finger grip and also had lower perceived postural variability and difficulty compared to that with the cylindrical shape. Our findings can be used to select appropriate umbrella handle designs based on grip type and wind conditions.

这项研究调查了不同形状的伞柄和抓握类型如何影响大风条件下的肌肉激活和姿势变化。十七名成人参与者参加了这项研究，并对不同的手柄形状（圆柱形、椭圆形和三棱柱形）、握把类型（四指和五指握把）和风力强度进行了测试。使用表面肌电图记录前臂和上臂肌肉的激活。测量了姿势变异性和（1）感知的使用难度和（2）感知的握力姿势变异性的评级。结果表明，在有风的条件下，手指屈肌的激活增加，而姿势变化不受影响。弱风（3.2-7.5 m/s）条件会导致更大的姿势变化和腕伸肌的激活。当用五指握持时，椭圆形手柄形状具有较低的终点姿势变化，并且与圆柱形手柄相比，其感知的姿势变化和难度也较低。我们的研究结果可用于根据握把类型和风力条件选择合适的伞柄设计。