Fig 1.
A.) Experimental design using real-time peak propulsive force measurements projected in front of participants with targets representing ±10 and 20% different from preferred. B.) Group average anterior-posterior ground reaction force by condition across time for all young (top left), all old (top right), RRLow (bottom left), and RRHigh (bottom right). Dashed grey lines represent young preferred walking as reference. An X on each curve provides a reference for the timing of peak FP. Asterisks (*) represent a significant main effect (p<0.05) of FP biofeedback on peak propulsive force.
Fig 2.
Group average hip and ankle joint powers by condition across time for all young (left) and all older adult subjects (right). Dashed grey lines represent young preferred walking as reference. An X on each curve provides a reference for the timing of peak FP. Asterisks (*) represent a significant main effect (p<0.05) of FP biofeedback on peak hip power during early stance (i.e., H1) and push-off (i.e., H3) and on peak ankle power.
Table 1.
Peak kinematic and kinetic outcome measures for all groups and conditions.
Fig 3.
Group average hip and ankle joint angles by condition across time for all young (left) and all older adult subjects (right). Positive values represent flexion. Dashed grey lines represent young preferred walking as reference. An X on each curve provides a reference for the timing of peak FP. Asterisks (*) represent a significant main effect (p<0.05) of FP biofeedback on peak joint extension.
Fig 4.
A.) Individual subject Redistribution Ratio (RR) value for Young, RRLow, and RRHigh. Single asterisks (*) represent a significant pairwise difference between RRHigh and Young. Double asterisks (**) represent a significant pairwise difference between RRHigh and RRLow, including preferred walking speed as a covariate B.) Group average and standard deviation Redistribution Ratio by increased propulsive force for Young (open circles), RRLow (dark grey circles), and RRHigh (light grey circles). Asterisks (*) represent a significant main effect (p<0.05) of increased FP biofeedback on the Redistribution Ratio.
Fig 5.
Group average hip and ankle joint powers by condition across time for RRLow (left) and RRHigh (right). Dashed grey lines represent young preferred walking as reference. An X on each curve provides a reference for the timing of peak FP. Asterisks (*) represent a significant main effect (p<0.05) of FP biofeedback on peak hip power during early stance (i.e., H1) and push-off (i.e., H3) and on peak ankle power.