Mechanics and energetics of post-stroke walking aided by a powered ankle exoskeleton with speed-adaptive myoelectric control.

Only six people were studied, and fewer completed the higher speeds, so the findings are unstable. All participants had to walk at least 0.6 m/s overground, so it says nothing about slower walkers. Speeds were not randomised; each speed was reached by increasing the treadmill each minute, so acclimation and fatigue may have affected later speeds. Metabolic cost was calculated over the whole speed ramp, which can miss delayed effects of changes in effort. Participants had limited time to get used to the exoskeleton, and one minute per speed may not have been enough to adapt. The exoskeleton restricted ankle movement and may have limited other foot rotations. No instructions were given to help participants optimise the assistance.

The work was funded by the National Institute of Nursing Research and the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The supplied text does not state author conflicts of interest.

Do not read the increased paretic ankle power as proof that walking became less costly. The whole-body metabolic cost did not improve, and only two of six participants had a lower cost while four had a higher cost.