摘要翻译：
重复性跌倒降低了老年人和各种神经疾病患者的生活质量。为了防止走路时跌倒，一个人应该依靠相关的早期动态平衡受损的指标。局部动态稳定性(LDS)代表步态对小扰动的敏感性：发散指数（最大Lyapunov指数）评估动力系统从邻近点发散的速度。虽然大量的发现证明LDS作为跌倒风险指标的有效性，但可靠性结果仍然很少。本研究利用腔内相关系数(ICC)和标准测量误差(SEM)探讨步态LDS的内、间重复性。95例健康人进行5min。每两次跑步机行走间隔9天。用三维加速度计测量躯干加速度。用3个时间尺度来估计LDS：超过4-10步（{\lambda}4-10)、超过1步（{\lambda}1步）和超过1步（{\lambda}0.5）。通过在5min内进行35步或70步的三次重复来评估运动内的重复性。会议间的重复性比较了两次会议，总共210步。{\lambda}4-10和{\lambda}1和{\lambda}0.5的ICCs（70步长估计值/35步长估计值）分别为0.52/0.18和0.84/0.77。闭会期间ICCs在0.60左右。扫描电镜结果显示，在中外侧方向测量的{λ}0.5具有最好的可靠性，足以检测到个体水平的中度变化（20%）。然而，由于会话间的重复性较低，为了更好地接近真实的LDS，应该对不同天的几次测量进行平均。
---
英文标题：
《Local dynamic stability of treadmill walking: intrasession and
  week-to-week repeatability》
---
作者：
Fabienne Reynard and Philippe Terrier
---
最新提交年份：
2013
---
分类信息：

一级分类：Quantitative Biology        数量生物学
二级分类：Other Quantitative Biology        其他定量生物学
分类描述：Work in quantitative biology that does not fit into the other q-bio classifications
不适合其他q-bio分类的定量生物学工作
--

---
英文摘要：
  Repetitive falls degrade the quality of life of elderly people and of patients suffering of various neurological disorders. In order to prevent falls while walking, one should rely on relevant early indicators of impaired dynamic balance. The local dynamic stability (LDS) represents the sensitivity of gait to small perturbations: divergence exponents (maximal Lyapunov exponents) assess how fast a dynamical system diverges from neighbor points. Although numerous findings attest the validity of LDS as a fall risk index, reliability results are still sparse. The present study explores the intrasession and intersession repeatability of gait LDS using intraclass correlation coefficients (ICC) and standard error of measurement (SEM). Ninety-five healthy individuals performed 5min. treadmill walking in two sessions separated by 9 days. Trunk acceleration was measured with a 3D accelerometer. Three time scales were used to estimate LDS: over 4 to 10 strides ({\lambda}4-10), over one stride ({\lambda}1) and over one step ({\lambda}0.5). The intrasession repeatability was assessed from three repetitions of either 35 strides or 70 strides taken within the 5min tests. The intersession repeatability compared the two sessions, which totalized 210 strides. The intrasession ICCs (70-strides estimates/35-strides estimates) were 0.52/0.18 for {\lambda}4-10 and 0.84/0.77 for {\lambda}1 and {\lambda}0.5. The intersession ICCs were around 0.60. The SEM results revealed that {\lambda}0.5 measured in medio-lateral direction exhibited the best reliability, sufficient to detect moderate changes at individual level (20%). However, due to the low intersession repeatability, one should average several measurements taken on different days in order to better approximate the true LDS.
---
PDF链接：
https://arxiv.org/pdf/1310.4946