Dominic Willoughby^1,2 (), Ryan P. MacPherson^2,3, Paula L. Silva⁴, Adam W. Kiefer^1,2,3; ¹Human Movement Science Curriculum, University of North Carolina at Chapel Hill, ²Matthew Gfeller Center, University of North Carolina at Chapel Hill, ³Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, ⁴Department of Psychology, University of Cincinnati

Efficient pursuit and interception of opponents is fundamental for successful contact-sport performance. However, the underlying perceptual-motor strategies athletes use to adapt deceleration patterns to changing demands remain unclear. Drawing from Lee (1976), Fajen and Devaney (2006) described a visual cue (based on optic flow rate and tau) that specifies “ideal” deceleration (i.e., the deceleration rate needed to stop just short of a target without requiring adjustments). In this study, we investigated whether and how athletes deviate from ideal deceleration—and thus from an adjustment minimization strategy—as target speeds approach maximal effort levels. Using a novel pursuit task in wireless virtual reality, 21 collegiate contact-sport athletes (9 females) ran in a 14×15m space to intercept virtual humanoid targets moving at 50%, 66.6%, 83.3%, or 100% of their maximum sprint speed. Positional data (60Hz) allowed calculation of deceleration onset distance, acceleration profiles, and root-mean-square error (RMSE) between ideal and observed deceleration patterns, normalized per participant. On all trials, athletes successfully intercepted the target before it reached the 15 m boundary edge. Linear mixed-effects models treated participants as random effects to evaluate condition-specific differences. Normalized RMSE values increased with target speed, increasing from 0.84 (50%) to 0.95 (83.3%) and 0.93 (100%), both p < 0.01, indicating greater deviation from ideal deceleration. Initial deceleration distances also shifted from 5.53m at 50% to 6.01m and 6.83m at 83.3% and 100%, respectively (p < 0.001). This suggests that athletes used a more aggressive deceleration strategy, characterized by a delayed initiation of deceleration and harder braking, as target speed increased. The similarity between 50% and 66.6% conditions demarcates a possible performance threshold where increasing task demands may prompt a shift in control strategies. Overall, these findings elucidate how athletes balance efficient motor execution with success in high-stakes tasks, offering insights for eventual training enhancement and rehabilitation interventions.

Acknowledgements: The authors would also like to thank Ainsley Mesnard and Max Zawel for their contributions to data collection and participant recruitment