Letter to the Editor Concerting the Article “Reproducibility and Repeatability of Five Different Technologies for Bar Velocity Measurement in Resistance Training” by Courel-Ibáñez et al. (2019)

  • Carlos Balsalobre-FernándezEmail author

We have read with great interest the article by Courel-Ibañez et al.5regarding the reproducibility and repeatability of different technologies for bar velocity measures. Authors should be congratulated for their structured and well-written study. However, there is a main issue with their data analysis that readers should be aware of. One of the main findings of this study is that a previously validated app based on slow-motion video analysis (VBS) is not reliable enough for the measurement of bar velocity in different resistance exercises. Specifically, it is shown that the smallest detectable change (SDC) of the app, when comparing two apps recording same lifts, ranges 0.13–0.22 m/s depending on the exercise. According to the low level of agreement between both apps when analyzing the same lifts, the authors state that VBS should not be recommended as a monitoring tool. Such strong statement conflicts what was extensively observed in the literature regarding the validity of VBS to...



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Copyright information

© Biomedical Engineering Society 2019

Authors and Affiliations

  1. 1.Universidad Autónoma de MadridMadridSpain

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