Evaluating the health and fitness benefits of a 6-month FES-cycling program on a recumbent trike for individuals with motor complete SCI: a pilot study

Background: Spinal cord injury (SCI) severely affects physical function, leading to muscle atrophy and reduced bone density. Sport-therapy, incorporating recreational and competitive activities, has shown promise in enhancing recovery for individuals with SCI. Functional Electrical Stimulation (FES)-cycling combines exercise benefits with stimulation advantages, and recent integration with mobile recumbent trikes adds further potential. This study aimed to evaluate the effects of a 6-month FES-cycling sport therapy using a recumbent trike on individuals with motor complete SCI. Methods: Five participants engaged in bi-weekly FES-cycling sessions using an instrumented recumbent trike. A comprehensive assessment was conducted before training, at 3 and 6 months of training, and at 1-month follow-up. Outcome measures included maximal muscle Cross-Sectional Area (maxCSA) from Magnetic Resonance Images, bone mineral density, clinical scales, and questionnaires on spasticity, pain, bowel dysfunction, psychological well-being, and sport motivation. Additionally, maximal power output and cycling endurance were assessed. Results: The FES-cycling program led to a significant increase in muscle mass of 34% after 6 months of training, correlated to an improved cycling performance (maxCSA versus peak power). A slight decrease of muscle mass was observed as expected at follow-up. Participants reported high well-being and strong motivation throughout the training program. Bone health, spasticity, bowel dysfunction, and pain levels did not significantly change overall. Conclusions: FES-cycling on a recumbent trike shows potential as a therapeutic and recreational activity for individuals with SCI. It significantly improved muscle mass and physical performance while positively impacting psychological well-being and motivation. Further research with larger cohorts is necessary to confirm these benefits and optimize protocols, establishing FES-cycling as a valuable sport-therapy model for SCI. Trial registration: The study protocol was retrospectively registered on clinicaltrials.gov (NCT06321172).