Pre- to post-season eye-tracking behavior and driving performance changes in rugby and tennis athletes across HDV and CAV conditions

Objective To examine pre- to post-season changes in eye-tracking behavior during simulated driving in rugby and tennis athletes under human-driven vehicle (HDV) and conditionally automated vehicle (CAV) conditions.Methods Thirty-two university athletes completed preseason testing (13 tennis, 19 rugby), and 17 returned for postseason testing (9 tennis, 8 rugby). Tennis athletes served as a low-contact comparison group and rugby athletes as a high-contact group. Participants completed randomized simulated driving scenarios in both HDV and CAV conditions. In the CAV condition, participants performed a 3-back non-driving-related task before takeover requests. Eye movements were recorded using Tobii Pro Glasses 3. Outcome measures included pupil diameter, fixation duration, fixation count, saccade amplitude, and saccade peak velocity. Generalized linear mixed models examined the effects of participant type, driving condition, time point, and their interactions.Results Rugby athletes demonstrated significantly larger pupil diameter than tennis athletes (p < .001). Significant main effects were found for saccade amplitude by participant type, driving condition, and time point (all p < .001), with lower amplitude observed in rugby athletes, in HDV relative to CAV, and at postseason relative to preseason. A significant participant type × time point interaction for saccade amplitude (p < .001) indicated that the difference between groups increased from preseason to postseason, with rugby athletes showing a greater reduction. Saccade peak velocity also showed significant main effects of participant type (p < .001) and driving condition (p < .001), as well as significant participant type × driving condition (p = .040) and participant type × time point (p < .001) interactions. Postseason saccade peak velocity was lower in rugby athletes than in tennis athletes. No significant effects were observed for fixation duration or fixation count.Conclusions Compared with tennis athletes, rugby athletes exhibited greater pre- to post-season changes in saccadic eye-movement metrics during simulated driving, with differences varying across HDV and CAV conditions. These findings suggest that participation in a contact sport may be associated with subtle changes in visual-attentional processes relevant to driving, particularly in the context of automated-driving transitions.