PMID 32908194

Research
All papers

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

Koontz AM, Garfunkel CE, Crytzer TM, Anthony SJ, Nindl BC

Question

Is a home-based handcycling HIIT program feasible, acceptable, safe, and preliminarily effective for individuals with spinal cord injury?

Summary

A small pilot trial tested 6 weeks of at-home supervised handcycling HIIT for wheelchair users with spinal cord injury. Most completers attended the supervised sessions and rated the program highly, and no study-related adverse events occurred. Group-level fitness outcomes did not significantly improve, and the study had no control group.

Methodology

  • Ten manual wheelchair users with spinal cord injury enrolled; seven completed. Mean age was 39.4 +/- 14.2 years; 7 male and 3 female; 7 tetraplegia and 3 paraplegia; 8 had incomplete injuries; mean time since injury was 12.4 +/- 10.6 years.
  • 10 participants.
  • Handcycling HIIT.
  • Work intervals: 1 min.
  • Recovery: 1 min.
  • Intensity: Work intervals at 90% peak power output +/- 5 W; recovery at 0-20% PPO; intensity criteria included HR >=90% HRmax and RPE >=17 for final intervals.
  • 25 min.
  • 2 supervised sessions, optional additional unsupervised sessions.
  • 6 weeks.
  • Pilot non-randomized clinical trial
  • Recruitment, retention, supervised session adherence, and intensity adherence, Enjoyment using PACES and satisfaction survey, Peak VO2, peak power output, and time to exhaustion, and Adverse events were tracked.

Outcomes

Seven of ten participants completed the program.

Seven of ten participants completed the program.

Mixed

Attendance

Six of seven completers attended all minimum supervised sessions; one completed 50% because of personal/work scheduling.

Mixed

Intensity fidelity

Of 89 sessions, 76 (85.4%) met at least one HIIT intensity criterion; 61.8% met at least two criteria and 23.6% met all three.

Mixed

Enjoyment and satisfaction

PACES enjoyment total was 114.8 +/- 11.3 out of a possible 126, and all survey respondents were very satisfied with HIIT and the trainer.

Mixed

Fitness outcomes

Fitness changes were not statistically significant among participants completing at least 12 sessions: peak VO2 was 14.3 +/- 5.0 to 14.3 +/- 4.8 mL/kg/min (p=.931), peak power output 60.0 to 65.0 W (p=.203), and time to exhaustion 6:17 to 6:49 (p=.194).

p=.931

Mixed

Insights

  • Adaptive HIIT can be highly acceptable when equipment and supervision are tailored to participants.
  • Feasibility evidence should not be converted into fitness efficacy claims because group-level fitness outcomes did not significantly change.
  • For users with SCI, HR and RPE alone may be insufficient; power targets and individualized monitoring are useful.

Limitations

  • Very small non-randomized pilot with no control group.
  • Mostly participants with incomplete injuries and many already physically active.
  • Specialized equipment and transfers may limit scalability.
  • HR and RPE may be unreliable in SCI.
  • Training mode differed from testing mode and 1-min upper-body intervals may have been too short.

Safety

  • No study-related adverse events occurred.
  • Dropouts included a pressure ulcer unrelated to study after 6 sessions, a new job after baseline, and a fall outside the study with femur fracture during the first week.