Heel or toe? Changes in step-down landing strategy following a fatiguing activity in older adults

AbstractIntroductionWalking is among the most reported activities preceding a fall in older adults, and negotiation on unlevel terrain is among the highest causes of walk-related falls. Exercise-induced fatigue alters gait, potentially increasing older adults’ fall risk during walking, but its effect on movement behaviour is unknown. We evaluated the effect of fatiguing activity on preferred landing strategy when stepping down a curb and whether landing strategy is associated with approach gait parameters. Individual variations were used to explore whether subgroups of more risk-taking or more cautious older adults could be identified.MethodTwenty-eight older adults (mean age: 78 years, 18 females) were assessed while walking 24 times (12 pre- and 12 post-fatiguing activity) on a walkway stepping down a 7.8 cm high curb after walking 7.5 meters. Fixed walking speed (1.1 m/s) was indicated alongside the walkway. Landing strategy (heel or toe) was visually classified. Gait variability and gait stability were measured during the approach using OpenCap markerless motion capture.ResultsNo changes in the proportion of landing strategy pre- to post-fatiguing activity were observed. MoS A-P was the only gait parameter associated with landing strategy, regardless of condition. Participants who decreased their proportion of toe landings were more often male than those who maintained their strategy.ConclusionFatiguing activity did not lead to changes in landing strategy. Although approach gait stability was associated with landing strategy and gender might influence individual changes, most older adults chose and maintained a more cautious strategy when stepping down a curb.