Does early exercise intolerance effect time to return to play, symptom burden, neurocognition, Vestibular-Ocular-Motor (VOM) function and academic ability in acutely concussed student-athletes?

<h4><b>Introduction</b></h4><p dir="ltr">Early Exercise Intolerance (EEI) is associated with delayed recovery and longer time to Return To Play (RTP), but this has not been established. Participants; (<i>n</i> = 52, male <i>n</i> = 30) UK university-aged rugby-union student-athletes.</p><h4><b>Methods</b></h4><p dir="ltr">Student-athletes completed baseline screening (July–October 2021 and 2022). The test battery was repeated within 48 h, 4, 8 and 14 days after a Sports-Related Concussion (SRC) with the Buffalo Concussion Bike or Treadmill Test to set sub-symptom heart rate threshold. Student-athletes then completed a controlled early exercise protocol in-between reassessment (days 3, 5–7 and 9–13). Those with EEI were compared to those with early-exercise tolerance.</p><h4><b>Outcome measures</b></h4><p dir="ltr"> Post-Concussion Symptom Scale, Immediate Post-Concussion and Cognitive Test, Vestibular-Ocular Motor Screening Tool and the Revised Perceived Academic Impact Tool.</p><h4><b>Results</b></h4><p dir="ltr">EEI was seen throughout the initial 14-days post-SRC (23.8%, 22.4%, 25.5%. 25.0%). EEI was associated with a slower reaction time within 48 h (−0.01 (−0.030–0.043) Vs 0.06 (0.033–0.24), <i>p</i> = 0.004) and greater VOMS scores within 48 h; (0.00 (0.00–4.00) Vs 5.50 (2.75–9.00), <i>p</i> = 0.016) and 4 days (0.00 (0.00–2.00) Vs 5.00 (0.00–6.00), p = 0.044). RTP was 12.5 days longer in those with EEI at 14-days post-SRC.</p><h4><b>Conclusion</b></h4><p dir="ltr">EEI is prevalent following an SRC in university-aged student-athletes and was associated with delayed recovery and RTP.</p>