Proprioception while standing is important for the balance control, but the proprioception has not been investigated in the unconstrained standing conditions. The purpose of this study was to investigate the effects of age and gender on the thresholds of perception and muscle response in response to the support surface rotation. The experiment was designed so that the thresholds depend mainly on the proprioception, i.e., quasistatic condition (0.2∘/s rotation of the platform) with eyes closed. Fifty-two healthy subjects (half young and half elderly) participated in this study. A platform was developed which can be rotated in four directions. Perception threshold angle was registered from subjects’ pressing a button. Muscle response threshold angle was determined as the earlier onset of EMG in lower limb muscles. Two standing conditions (feet together and natural stance) were tested. Repeated-measures ANOVA showed that both thresholds increased with age. Post hoc tests revealed (1) that the perception threshold was greater for women than men in the elderly and (2) both thresholds of the elderly were greater for the feet-together stance than natural stance. Inferior perception sensitivity of platform rotation in elderly women may be associated with inferior performance in cortical postural control and greater fall ratio compared to elderly men, which suggests the need of proprioception trainings.

中文翻译：

---

支持表面旋转的感知和肌肉反应阈值的年龄性别差异

站立时的本体感觉对平衡控制很重要，但本体感觉尚未在不受约束的站立条件下进行研究。本研究的目的是调查年龄和性别对响应于支撑表面旋转的感知阈值和肌肉反应的影响。实验的设计使得阈值主要取决于本体感觉，即准静态条件（0.2∘/s 平台旋转）闭上眼睛。五十二名健康受试者（一半年轻，一半老年人）参加了这项研究。开发了一个可以在四个方向上旋转的平台。从受试者按下按钮记录感知阈值角度。肌肉反应阈值角被确定为下肢肌肉中 EMG 的早期发作。测试了两种站立条件（双脚并拢和自然站立）。重复测量方差分析表明，这两个阈值都随着年龄的增长而增加。事后测试显示 (1) 老年人中女性的感知阈值高于男性，(2) 老年人的两个阈值对于双脚并拢的姿势都高于自然姿势。