Elite football players achieve pre-injury running performance despite MRI lesions after return to play without increased risk of recurrence.

Aim of this prospective cohort study was to assess the value of MRI findings as a return to play (RTP) criterion in relation of safety to achieve pre-injury running performance in the initial days after RTP. All acute non-contact muscle injuries sustained by first-team and farm-team football players of a leading country club from January 2023 to December 2024 were analysed. The rehabilitation was performed according to the control chaos continuum framework. A total of 69 acute primary non-contact muscle injuries occurred during the study period. In twelve cases, MRI was performed both immediately after injury and after RTP (control MRI). The Players returning to play after 29 ± 15.53 days. Control MRI showed that while the degree of injury remained unchanged, the volume of the oedema had decreased (p < 0.001). Peak speed, deceleration, and acceleration intensity were comparable to pre-injury levels post-RTP (p = 0.237, p = 0.184, and p = 0.398, respectively). MRI changes persist after RTP seeming not to impair the ability to perform sport-specific activities at pre-injury levels, nor did they increase the risk of injury recurrence in the participants of this study.