This study adds new information about pacing strategy in ultramarathon running races. It complements previous studies on this issue and provides interesting insights after decomposing pacing strategy on level ground, uphill and downhill components. Definitely, a useful approach to be considered for future studies on different endurance sports. Importantly, the option of investigating "the dynamics of speed relative to each participant’s average speed over the entire event (100%)" deserves merit, since this aspect of pacing comparisons is often forgotten in many studies.
Given that feedback is supposedly one of the aims of preprint publications, I'd like to offer some suggestions to improve the final work.
L39-40: If possible, try to update these references. Especially because one relates to relatively short distances and the other is not really accessible in many universities.
L47&151: Do we really need abbreviations? It's always easier to read a paper without abbreviations.
L56-59: I think you should focus on ultramarathon running only. There are enough references for you to introduce and discuss, including some recently published papers:
Bossi, A. H., Matta, G. G., Millet, G. Y., Lima, P., Pertence, L. C., de Lima, J. P., & Hopker, J. G. (2016). Pacing Strategy During 24-hour Ultramarathon-Distance Running. International journal of sports physiology and performance, 1-25.
Renfree, A., Crivoi do Carmo, E., & Martin, L. (2016). The influence of performance level, age and gender on pacing strategy during a 100-km ultramarathon. European journal of sport science, 16(4), 409-415.
Tan, P. L., Tan, F. H., & Bosch, A. N. (2016). Similarities and differences in pacing patterns in a 161 and 101 km ultra-distance road race. Journal of strength and conditioning research/National Strength & Conditioning Association.
L100: I think there is a typo here.
L187: Perhaps "Relative speed was the most variable in LEV" could be changed to "Relative speed varied the most in LEV". I had trouble to understand the first time I read.
L205-206: Given that "a speed reserve was measured in LEV and UH", whether your analyses describe a parabolic rather than a positive pacing strategy should be considered.
Figure 2: Possibly you could add a bit more information in the legend, making the reader understand the brackets easier.
L239-240: Perhaps you could mention the following work on these lines:
Hoffman, M. D., Badowski, N., Chin, J., Stuempfle, K. J., & Parise, C. A. (2016). Determinants of recovery from a 161-km ultramarathon. Journal of sports sciences, 1-9.
Conclusion: I missed the practical applications of your work. I think you could explore them.
I hope you take my comments constructively to further increase the value your original contribution.
Arthur Henrique Bossi | PhD student
School of Sport & Exercise Sciences, University of Kent
Medway Building, Chatham Maritime, Chatham, Kent, ME4 4AG, UK
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