The authors have retracted this article [1] because after publication it was brought to their attention that the statistical approach is not appropriate. The authors are re-analysing their data and intend to submit a new manuscript for peer review in due course. All authors agree to this retraction.

[1] Siddique U, Rahman S, Frazer AK, Howatson G, Kidgell D. Sports Med (2019). https://doi.org/10.1007/s40279-019-01152-3