Metabolic rate and cardiorespiratory response during hybrid cycling versus handcycling at equal subjective exercise intensity levels in people with spinal cord injury

Objective: To compare the metabolic rate and cardiorespiratory response during hybrid cycling versus handcycling at equal subjective exercise intensity levels in people with spinal cord injury (SCI). Design: Cross-sectional study. Setting: Amsterdam Rehabilitation Research Centre vertical bar Reade, Amsterdam, The Netherlands. Methods: On separate days, nine individuals with a motor complete paraplegia or tetraplegia (eight men, age 40 +/- 13 years, time since injury 12 +/- 10 years) performed 5-minute bouts of hybrid cycling (day 1) and handcycling (day 2) at moderate (level 3 on a 10-point rating of perceived exertion (RPE) scale) and vigorous (RPE level 6) subjective exercise intensity, while respiratory gas exchange was measured by open-circuit spirometry and heart rate was monitored using radiotelemetry. Outcome measures: Metabolic rate (calculated with the Weir equation) and cardiorespiratory response (heart rate, oxygen pulse, and ventilation). Results: Overall, the metabolic rate during hybrid cycling was 3.4 kJ (16%) higher (P = 0.006) than during handcycling. Furthermore, compared with handcycling, the overall heart rate and ventilation during hybrid cycling was 11 bpm (11%) and 5.3 l/minute (18%) higher (P = 0.004 and 0.024), respectively, while the oxygen pulse was the same (P = 0.26). Conclusion: Hybrid cycling induces a higher metabolic rate and cardiorespiratory response at equal RPE levels than handcycling, suggesting that hybrid cycling is more suitable for fighting obesity and increasing cardiorespiratory fitness in individuals with SCI.