The Effects of Using Geared Wheels on Energy Expenditure During Manual Wheelchair Propulsion in Adults with Spinal Cord Injury

Objectives: To quantify the effects of geared wheelchair wheels on energy expenditure during manual wheelchair propulsion in individuals with spinal cord injury (SCI). Methods: Eleven adult manual wheelchair users with SCI propelled their personal manual wheelchairs, which were equipped with a pair of geared wheels, on a passive wheelchair ergometer in low-gear and standard-gear conditions for six minutes. The energy cost of transport, distance traveled, rate of oxygen consumption (SCI MET), rate of perceived exertion, heart rate, and stroke cycle frequency were measured and compared across the gear conditions. Results: The distance traveled and SCI MET were significantly lower (p = 0.003) and cost of transport was significantly higher under the low-gear condition compared with the standard-gear condition. Gear condition exerted a moderate effect on the level of exertion; however, the decrease in the rate of perceived exertion under the low-gear condition was not statistically significant. Gear condition did not significantly affect heart rate and stroke cycle frequency. Conclusions: Geared manual wheelchair propulsion was significantly more energy-demanding, but less intense (easier) under the low-gear condition than the standard-gear condition. Using geared wheels may be beneficial for manual wheelchair users to independently accomplish strenuous propulsion tasks during typical activities of daily living, such as propulsion on carpeted floor. However, the small sample size and inclusion of only male participants limit the generalizability of these findings, and future studies with larger and more diverse cohorts are warranted.