BACKGROUND Physical activity is linked to many positive health outcomes, stimulating the development of exercise programs. However, many falls occur while walking and so promoting activity might paradoxically increase fall rates, causing injuries, and worse quality of life. The relationship between activity exposure and fall rates remains unclear. We investigated the relationship between walking activity (exposure to risk) and fall rates before and after an exercise program (V-TIME). METHODS One hundred and nine older fallers, 38 fallers with mild cognitive impairment (MCI), and 128 fallers with Parkinson's disease (PD) were randomly assigned to one of two active interventions: treadmill training only or treadmill training combined with a virtual reality component. Participants were tested before and after the interventions. Free-living walking activity was characterized by volume, pattern, and variability of ambulatory bouts using an accelerometer positioned on the lower back for 1 week. To evaluate that relationship between fall risk and activity, a normalized index was determined expressing fall rates relative to activity exposure (FRA index), with higher scores indicating a higher risk of falls per steps taken. RESULTS At baseline, the FRA index was higher for fallers with PD compared to those with MCI and older fallers. Walking activity did not change after the intervention for the groups but the FRA index decreased significantly for all groups (p ≤ .035). CONCLUSIONS This work showed that V-TIME interventions reduced falls risk without concurrent change in walking activity. We recommend using the FRA index in future fall prevention studies to better understand the nature of intervention programs.

中文翻译：

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高风险老年人的跌倒风险与活动暴露有关。


背景技术身体活动与许多积极的健康结果相关，刺激锻炼计划的制定。然而，许多跌倒发生在步行时，因此促进活动可能会增加跌倒率，导致受伤并降低生活质量。活动暴露与跌倒率之间的关系仍不清楚。我们调查了锻炼计划前后的步行活动（暴露风险）与跌倒率之间的关系 (V-TIME)。方法 109 名老年跌倒者、38 名患有轻度认知障碍 (MCI) 的跌倒者和 128 名患有帕金森病 (PD) 的跌倒者被随机分配接受两种主动干预措施之一：仅跑步机训练或跑步机训练与虚拟现实相结合。参与者在干预之前和之后接受了测试。自由生活步行活动的特征是使用位于下背部的加速度计持续 1 周的步行次数、模式和变化性。为了评估跌倒风险与活动之间的关系，确定了一个标准化指数，表示相对于活动暴露的跌倒率（FRA 指数），分数越高表明每走一步跌倒的风险越高。结果 在基线时，PD 跌倒者的 FRA 指数高于 MCI 跌倒者和老年跌倒者。各组的步行活动在干预后没有变化，但所有组的 FRA 指数均显着下降 (p ≤ .035)。结论 这项工作表明，V-TIME 干预措施可以降低跌倒风险，而无需同时改变步行活动。我们建议在未来的跌倒预防研究中使用 FRA 指数，以更好地了解干预计划的性质。