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bioRxiv · 10.1101/2025.07.11.664350

RACLET: the Ramp Above Critical Level Endurance Test to evaluate critical velocity in running.

Vonderscher, M.·Samozino, P.·Bowen, M.·Morel, B.
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Abstract

Critical velocity (Vc) is an important fatigability threshold in running, but only strenuous methods exist to assess it (e.g. time-trials). Based on a novel mathematical model of fatigability, the Ramp Above Critical Level Endurance Test (RACLET), a simple, non-exhaustive, 5-min test to evaluate Vc was developed. This study aimed to test the reliability and validity of the RACLET. Thirty-eight participants performed two RACLET (session 1) and three time-trials (sessions 2-4). For the RACLET, velocity target tracking was guaranteed by either a pacing bike or cones and whistle signals. GPS was used to measure the participants running velocities. Vc,{tau} , and [Formula] were determined by adjusting the fatigability model on the measured Vmax. The RACLET test-retest and RACLET vs. time-trials parameters were compared for reliability and validity testing, respectively. The RACLET Vc is reliable and valid (mean difference=-1.7{+/-}1.9% and 6.2{+/-}6.5%, respectively). Although{tau} and [Formula] presented important variability (s.d. difference ~30%), the combination of the RACLET parameters enabled an excellent prediction of time-trials performance (mean error=-8.9{+/-}5.1%, 0.9{+/-}7.4%, -2.0{+/-}5.2% for 400, 1500, and 3000 m, respectively). RACLET is a novel non-exhausting test that enables a reliable and valid assessment of the velocity-time relationship parameters.

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Vonderscher, M., Samozino, P., Bowen, M., Morel, B.. 2025-07-15. RACLET: the Ramp Above Critical Level Endurance Test to evaluate critical velocity in running.. https://doi.org/10.1101/2025.07.11.664350

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