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bioRxiv · 10.1101/2023.10.25.564056

Quantifying the performance benefits of middle distance running super spikes

Bertschy, M.·Rodrigo Carranza, V.·Wilkie, E. W. C.·Healey, L. A.·Noble, J.·Albert, W. J.·Hoogkamer, W.
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Abstract

BackgroundQuantifying the potential benefits of advanced footwear technology (AFT) track shoes (i.e., "spikes") in middle-distance events is challenging, because repeated maximal effort trials (as in sprinting) or aerobic running economy trials (as in long-distance running) are not feasible. MethodsWe introduce a novel approach to assess the benefits of AFT spikes, consisting of a series of 200 m runs at self-perceived middle-distance race pace with 10 min recovery and conducted four experiments to evaluate its validity, sensitivity, reproducibility, and utility. ResultsIn experiment 1, participants ran 1.2% slower in spikes with 200 g added mass vs. control spikes, exactly equal to the known effects of shoe mass on running performance. In experiment 2, participants ran significantly faster in AFT prototype spikes vs. traditional spikes. In experiment 3, we compared two other AFT prototype spikes against traditional spikes, on three separate days. Group-level results were consistent across days, but our data indicates that at least two separate sessions are needed to evaluate individual responses. In experiment 4, participants ran significantly faster in two AFT spike models vs. traditional spikes (2.1% and 1.6%). Speed was similar between a third AFT spike model and the traditional spikes. These speed results were mirrored by changes in step length, as participants took significantly longer steps in the two faster AFT spike models (2.3% and 1.9%), while step length was similar between the other spikes. ConclusionOur novel, interval-based approach is a valid and reliable method to quantify differences between spikes at middle-distance running intensity.

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Bertschy, M., Rodrigo Carranza, V., Wilkie, E. W. C., Healey, L. A., Noble, J., Albert, W. J., Hoogkamer, W.. 2023-10-29. Quantifying the performance benefits of middle distance running super spikes. https://doi.org/10.1101/2023.10.25.564056

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