Comment on “Hurdle Clearance Detection and Spatiotemporal Analysis in 400 Meters Hurdles Races Using Shoe-Mounted Magnetic and Inertial Sensor”

Round 1

Reviewer 1 Report

The comment from Schmidt et. al. point out very relevant and interesting comments on the paper "Hurdle clearance detection and spatio-temporal analysis in 400 meters hurdles races using Shoe-mounted Magnetic and Inertial Sensors".

I believe that, in their response, the authors rightfully explained the limitations of their experiments highlighting the fact that the lack of the instantaneous speed measurements will hinder a good estimation of the bias. However, I think that some improvements in the argument that the wavelet filtering will not introduce a bias should be demonstrated with results. The authors could for example apply the wavelet filtering in their previous work (M. Falbriard et. al., Frontiers in physiology, 9, 610, 2018) to demonstrate that in fact there are no significant changes in the conclusions regarding the bias dependence on the speed. 

Finally, I am not really convinced about the argument that other errors "such as the sensors fixation, functional calibration, and the filtering methods have a more significant impact on the shape of the signal than the difference between treadmill and overground running" because no experimental results proving this were presented. I can imagine that it is indeed the case and take the authors word for it but a real prove is not presented in the original document nor in this response. I would therefore advise the authors either to add an example that support the aforementioned sentence or simply remove it as the authors further acknowledge that a bias can come with the change from the treadmill to overground running and that this could be investigated in the future.