An Exploratory Analysis of Countermovement Jump Variables Between Higher and Lower Performers on the LESS and Y-Balance Tests.

The authors' own calculation said 260 athletes were needed to detect differences and only 109 were tested, so real differences may well have been missed and results could shift in a larger sample. Each athlete performed only two jumps on one day, which may not reflect their usual mechanics or day-to-day variation. The At Risk Flag Count is the authors' own invention, has never been validated, and the authors themselves say it should not be used as a diagnostic or predictive tool. No analysis adjusted for sex or sport, and the female and per-sport subgroups were small, so subgroup findings may be chance. Leg and hand dominance were never recorded, so the authors could not test whether dominance explains the asymmetry findings. Nobody was followed up, so the study cannot show that any of these jump metrics predict injury.

The authors declare they have no financial or personal relationships that could be seen as a conflict of interest. No funding source is stated in the text provided.

Do not read this as evidence that countermovement jump metrics on force plates can predict ACL injury. No athlete was followed up to see who got injured, the sample was less than half the size the authors' own calculation called for, and several findings come from small sex subgroups. These are associations to test in future studies, not screening thresholds to apply now.