The impact of pedestrian body steering movements on collision avoidance and gaze behaviours: Potential influence of athletic training.

Individuals constantly adapt their locomotion to navigate through complex environments and avoid collisions with other pedestrians. Vision is primarily used to inform individuals about possibilities for action within an environment. While several studies have explored gaze behaviour during pedestrian interactions, less is known about how individuals direct their gaze when avoiding an approaching pedestrian and how athletic training may influence visuo-locomotor control strategies. The purpose of the study was to determine how visual cues about an approaching pedestrian's body segment movements affect collision avoidance behaviours in a daily context, and whether high-level sport training influences such avoidance and gaze behaviours. Sixteen female varsity soccer players (Athletes, 22.25 yrs. ± 2.14) and eleven aged-matched control participants from the general university population (Controls, 23.00 yrs. ± 2.93) were immersed in a virtual shopping mall and instructed to avoid a virtual pedestrian who initially approached and then either steered left, right, or continued walking straight. The stereotypic rotation sequences of the pedestrian's eyes, head, and trunk for direction steering were manipulated over six conditions ranging from normal segmental timing and movement to different levels of ambiguous information in relation to some segments not rotating or not following normal sequences. Both Controls and Athletes initiated path deviation at a similar distance from the pedestrian, while Athletes were less variable. All participants directed their gaze mostly at the pedestrian and fixated primarily the head of the pedestrian. All participants' minimal clearance became smaller and more variable with higher ambiguity in steering behaviours of the pedestrian, although Athletes were less variable. Exploratory post-hoc analyses revealed individual differences in initial path deviation and gaze behaviours within the athlete group, suggesting heterogeneity in strategies. Results suggest that the gait profile of an approaching pedestrian affects path planning and that sport-specific training may influence daily navigation.