Department of Physical Education, Sports and Recreation, Universidad de La Frontera, Temuco, Chile.
Department of Corporal Expression, University of Jaen, Jaen, Spain.
J Biomech. 2019 Aug 27;93:213-219. doi: 10.1016/j.jbiomech.2019.06.017. Epub 2019 Jun 28.
The aim of this study was to determine the level of agreement between spatiotemporal gait characteristics from a photoelectric system with different filter settings and high-speed video analysis during running on a treadmill at comfortable velocity. Forty-nine runners performed a running protocol on a treadmill at comfortable velocity. Two systems were used to determine spatiotemporal parameters (i.e. contact time [CT], flight time [FT], step frequency [SF] and step length [SL]) during running: OptoGait system and high-speed video analysis at 1000 Hz. The collected data was re-filtered in the OptoGait software by using nine different settings (i.e. 0_0, 1_1, 2_2, 3_3, 3_4, 4_4, 4_5, 5_4 and 5_5), and compared to those obtained through video analysis. The Pearson correlation analysis revealed very large correlations (r > 0.9, p < 0.001) in CT, FT, SF and SL between both systems, regardless of the OptoGait's filter settings. The ICC reported an almost perfect association (ICC > 0.9) for both SL and SF regardless of the filter setting. However, large variations between filter settings according to the data from video analysis were reported in CT and FT (0_0, 1_1 and 2_2 filter settings obtained an association ICC > 0.9, whereas other filters obtained lower ICCs). Bland-Altman plots revealed small bias and error and no presence of heteroscedasticity of error for 1_1 setting. In conclusion, the filter setting for the OptoGait system should be considered to minimize the bias and error of spatiotemporal parameters measurement. For running on a treadmill, the 1_1 filter setting is recommended if gait parameters are to be compared to a high-speed video analysis (1000 Hz).
本研究旨在确定在舒适速度下在跑步机上跑步时，不同滤波设置的光电系统与高速视频分析得出的时空步态特征之间的一致性水平。49 名跑步者在跑步机上以舒适速度进行跑步方案。使用两个系统来确定跑步时的时空参数（即接触时间[CT]、腾空时间[FT]、步频[SF]和步长[SL]）：OptoGait 系统和以 1000 Hz 的高速视频分析。在 OptoGait 软件中，通过使用九种不同的设置（即 0_0、1_1、2_2、3_3、3_4、4_4、4_5、5_4 和 5_5）对收集的数据进行重新滤波，并将其与视频分析获得的数据进行比较。Pearson 相关分析显示，无论 OptoGait 的滤波设置如何，在 CT、FT、SF 和 SL 方面，两种系统之间均存在非常大的相关性（r>0.9，p<0.001）。ICC 报告说，无论滤波设置如何，SL 和 SF 的关联性几乎都是完美的（ICC>0.9）。然而，根据视频分析数据，CT 和 FT 报告了不同的滤波设置之间的差异（0_0、1_1 和 2_2 滤波设置获得的关联 ICC>0.9，而其他滤波器获得的 ICC 较低）。Bland-Altman 图显示，1_1 设置的偏差和误差较小，且不存在误差的异方差性。总之，应考虑 OptoGait 系统的滤波设置，以最大程度地减少时空参数测量的偏差和误差。如果要将步态参数与高速视频分析（1000 Hz）进行比较，则建议在跑步机上跑步时使用 1_1 滤波设置。
