Electromyographic reaction time in older female fallers and non-fallers after postural perturbation

The electromyographic reaction time (ERT) reflects the magnitude and speed with which muscles are activated to perform movements, to prevent injuries, or to position a joint. This parameter can be used to analyze postural control performance after an external perturbation and can be correlated with the possibility of falls in older adults. The objective of this study was to determine the ERT of the internal oblique, rectus femoris, vastus lateralis, tibialis anterior, multifidus, gluteus maximus, biceps femoris, and lateral gastrocnemius muscles to balance threats in older adults with and without a history of falls. Twenty-nine physically active and noninstitutionalized women aged 60 years or older were divided into two groups: fallers (n=13; 72.4 ± 8.0 years) and non-fallers (n=16; 67.8 ± 6.8 years). The ERT of the muscles tested did not differ significantly between groups following forward or backward perturbations. The results suggest that the activation of the muscles tested in response to forward or backward perturbations is not a determinant factor of falls肌电反应时（electromyographic reaction time, ERT）反映了肌肉为完成动作、预防损伤或维持关节位置而被激活的幅度与速度。该参数可用于分析外部扰动后的姿势控制表现，且与老年人跌倒风险具有相关性。本研究旨在测定有跌倒史与无跌倒史老年人群的腹内斜肌、股直肌、股外侧肌、胫骨前肌、多裂肌、臀大肌、股二头肌及腓肠外侧肌在应对平衡威胁时的肌电反应时。本研究共招募29名60岁及以上、日常活动良好且非机构养老的女性，将其分为两组：跌倒组（n=13；年龄72.4 ± 8.0岁）与非跌倒组（n=16；年龄67.8 ± 6.8岁）。正向或反向平衡扰动后，两组受试肌肉的肌电反应时均无显著差异。研究结果表明，受试肌肉在应对正向或反向扰动时的激活情况，并非老年人跌倒的决定性因素。