Objective Establish the natural history of clinical signs and OVRT function in motorsport. Major hypothesis (creating a normative dataset); OVRT function of motorsport athletes is not adversely affected by sports participation.

Design Two-year cross-sectional and longitudinal observational sub-/studies (baseline, post-participation).

Setting Two sport-specific participant identification centres (PICs), single secondary care enrolment site. Data were collected trackside in two time zones from three sporting venues at endurance events (3–24hrs).

Participants n=50 participants at baseline, of which n=9 entered and completed sub-study follow-up; 100% male. Criteria (selection: local identification at PIC; entry: competitive motorsport participants; exclusion: age<16years, prior severe/moderate traumatic brain injury (TBI), mild TBI within 6months, head injury symptoms)).

Outcome Measures all outputs were pre-specified, as identified from available literature.

Main Results n=30 post-participation OVRT assessments were analysed using group comparison statistics. Four variables differed significantly post-participation across ocular (smooth pursuit) and reaction time (RT) tasks. Percentage of saccades (fast horizontal; t(8)=-2.917, p=0.019; vertical (t(8)=-3.981, p=0.004) and mean RT decreased (visual (t(8)=-3.327, p=0.010; auditory (t(6)=-3.030, p=0.023). Aside from the latter (medium), all effect sizes were large.

Conclusions Sports participation results in enhanced performance on ocular and RT tasks as captured with a novel 3D headset. Post-participation differed significantly from pre-season data and may represent a more appropriate baseline than traditional office-based assessment. Future work will develop the trackside diagnostic tool by comparing post-participation to post-injury OVRT data, exploring OVRT function as correlated to concussion severity throughout the acute post-injury period.

Trial Registration National (Central Portfolio Management System 38259), International (ClinicalTrials.gov NCT03844282).