Avoidance and accommodation of surface height changes by healthy, community-dwelling, young, and elderly men.

The purpose of this study was to compare avoidance and accommodation strategies during gait between healthy, community-dwelling, young and elderly males. Ten young (28.4 +/- 5.4 years) and ten elderly (69.5 +/- 6.1 years) males were tested while walking on the level, avoiding a 11.75-cm-high obstacle, and accommodating a change in floor height of 11.75 cm. Three dimensional, kinematic, and kinetic analyses were performed bilaterally. Both age groups used the same general sagittal plane strategies in order to avoid and accommodate the obstructions, but the elderly group had significantly reduced lead toe clearances. These riskier toe clearances by the elderly group were found to be due to limited, frontal plane pelvic motion, shorter stride lengths, and subtle differences in the interplay of lower limb energetic patterns within the sagittal plane. These results are discussed with respect to diminishing physical capacity in the elderly populations.