A novel push-pull central-lever mechanism reduces peak forces and energy-cost compared to hand-rim wheelchair propulsion during a controlled lab-based experiment.

The participants were able-bodied novices with no wheelchair experience, so the findings do not show what manual wheelchair users would experience or tolerate. The study was a short, controlled lab treadmill experiment with fixed speed and power, not real-world wheelchair use, slopes, curbs, or transfers. The tested RoChair prototype was difficult to step into and get out of, so it is not yet ready as an everyday wheelchair for manual wheelchair users. Some outcomes were analysed with fewer participants because of equipment errors, including heart rate in the lever group with n = 12 for both sessions and energy expenditure in the lever group with n = 14 at post. The lever did not significantly differ from the hand-rim for gross mechanical efficiency, heart rate, perceived exertion, or stroke frequency. The study did not report joint loads or muscle activity, so lower peak force does not establish reduced shoulder or upper-limb strain. The study compared novices learning both devices, so it may not reflect experienced hand-rim users' technique or the added skill demands of the lever.

ROTA Mobility funded the work; the supplied text does not provide author conflict disclosures.

Do not treat the lower peak forces as evidence that this wheelchair reduces strain or injury risk for manual wheelchair users. The study tested able-bodied novices in a controlled lab, did not report joint loads or muscle activity, and the prototype was not yet easy to transfer into or out of.