Effect of fatigue on stride pattern continuously measured by an accelerometric gait recorder in middle distance runners.
Effect of fatigue on stride pattern continuously measured by an accelerometric gait recorder in middle distance runners.
复制标题
通过加速步态记录仪连续测量中长跑运动员的疲劳对步幅模式的影响。
DOI：
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复制
发表时间：
2006
影响因子：
1.7
通讯作者：
E. Barrey
中科院分区：
文献类型：
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作者：
R. Le Bris;V. Billat;B. Auvinet;D. Chaleil;L. Hamard;E. Barrey
目的
本研究的目的是分析运动员在VO（2 max）速度下步幅模式的连续变化。
方法
6名亚优秀男子中长跑运动员以最大有氧速度（17.4+/-1.1 km·h（-1））进行了恒定的场地跑测试至力竭（力竭时间：409+/-71 s）。身体加速度测量与三轴加速度计固定在后腰。从加速度计输出计算一组变量：步幅频率、步幅对称性和规律性、每个轴上的信号能量和脉冲以及总加速度矢量的积分。采用重复测量的方差分析方法，对运动起始点、运动中间点和运动结束点三个时间段内这些变量的变化进行检验。
结果
结果表明：描述连续步幅前后运动相似性的规律性指数在实验开始和结束时显著降低（309.9 ~ 274.5; P<0.05）;在同一时间内，内侧-外侧脉冲（4.69%BW. s至5.71%BW. s; P<0.001; BW：体重）和信号能量（1.40 G（2）.s至2.06 G（2）.s; P<0.001; G=9.81 m.s（-2））显著增加。
结论
运动员在疲劳状态下，中-外侧轴的变化（不利于推进的能量消耗的增加）和规律性指标的变化（运动周期的时空周期性的改变）可以被认为是运动员跑步模式的早期改变。
AIM
The purpose of this study was to analyze the continuous changes in stride patterns of athletes running at speed elicited VO(2max).
METHODS
Six male sub-elite middle-distance runners carried out a constant track running test to exhaustion (time to exhaustion: 409+/-71 s) at their maximal aerobic speed (17.4+/-1.1 km.h(-1)). The body accelerations were measured with a triaxial accelerometer fixed at the low back. A set of variables was computed from the accelerometer output: stride frequency, stride symmetry and regularity, signal energies and impulses in each axis and the integral of the total acceleration vector. An ANOVA with repeated measures was performed to test the changes of these variables during the three times: the onset point, midway point and end point of exercise.
RESULTS
The following changes were observed: the regularity index which describes the similarity of crania-caudal movements over successive strides, decreased significantly between the start and the end of the test (309.9 to 274.5; P<0.05). During the same time, the media-lateral impulse (4.69%BW.s to 5.71%BW.s; P<0.001; BW: body weight) and signal energy (1.40 G(2).s to 2.06 G(2).s; P<0.001; G=9.81 m.s(-2)) increased significantly.
CONCLUSIONS
The changes in medio-lateral axis (increase of energy expenditure which is not useful for propulsion) and in the regularity index (modifications in the temporal-spatial periodicity of the running cycle) could be considered as early alterations of running pattern when the athletes got fatigued.