Feasibility, acceptability, and preliminary efficacy of a handcycling high-intensity interval training program for individuals with spinal cord injury.

Study Design: Pilot nonrandomized clinical trial.
Objectives: To examine the feasibility, acceptability, and preliminary efficacy of performing handcycling high-intensity interval training (HIIT) for 6 weeks in wheelchair users with spinal cord injury.
Setting: Participant's home.
Methods: Participants completed pre- and postgraded exercise stress tests, exercise surveys and 6 weeks of handcycling HIIT. The HIIT program consisted of two weekly, 25 min supervised at-home sessions (2-3 min warm-up, then ten intervals of cycling with a ratio of 1 min work at 90% peak power output (PPO) to 1 min recovery at 0-20% PPO, then 2-3 min cool down). Real-time power output and heart rate were recorded via sensors and a bike computer. The sensor data were analyzed to evaluate training efficacy.
Results: Seven of the ten enrolled participants (70%) completed the study. All but one completed the required 12 sessions. The participants met at least 1 of the HIIT target intensity criteria in 76 out of 89 total sessions (85.4%) performed. Participants expressed a high level of enjoyment on the Physical Activity Enjoyment Scale, mean (SD) = 114.8 (11.3), and satisfaction with the overall experience. Five of the seven participants (71%) who completed the study felt an increase in endurance, function, and health. Objective physiological changes showed mixed results.
Conclusions: Six weeks of handcycling HIIT appears to be safe, feasible and acceptable. A longer HIIT work interval may be needed to elicit significant physiological responses. Future investigation of the feasibility and efficacy of differing HIIT parameters is needed.