Affiliations: [a] Center for Neuromotor and Biomechanics Research, University of Houston, Houston, TX, USA | [b] Methodist Neurological Institute, Houston, TX, USA
Correspondence:
[*]
Address for correspondence: Adam Thrasher, Center for Neuromotor and Biomechanics Research, University of Houston, Houston, 3855 Holman Street, Garrison Room 104, Houston, TX 77204-6015, USA. Tel.: +1 713 743 5276; Fax: +1 713 743 9860; E-mail: athrasher3@uh.edu
Abstract: Objectives:To describe adaptations in power output, quadriceps muscle strength, and fatigability that occur during a 13-week regimen of Functional Electrical Stimulation Leg Cycle Ergometry (FES-LCE) in Spinal Cord Injury (SCI). To identify differences in outcomes between individuals with complete and incomplete motor impairment. Design:Observational and longitudinal. SETTING: Rehabilitation and biomechanics research laboratory. Participants:Eleven (N = 11) individuals with SCI and no previous FES-LCE experience. Intervention:40 sessions of FES-LCE at a rate of three sessions per week. Continuous exercise was performed at a pedal cadence of 45 RPM against a constant resistance for up to 60 minutes. Outcome measures:Mean power output was recorded for each session. Before and after the training regimen, each subject performed a fatigue test in which electrically stimulated knee extension torque and Fatigue Index were measured. Results:Participants demonstrated significant increases in mean power output (9.0 to 20.3 W; p < 0.001), peak isometric knee extension torque (3.8 to 16.9 Nm; p = 0.006) and sustainable isometric knee extension torque (4.9 to 14.4 Nm; p = 0.001) after FES-LCE training (95% confidence intervals). Participants with incomplete motor impairment demonstrated a decrease in Fatigue Index (p = 0.021), and improved mean power output more than those with complete motor impairment (p = 0.037). Conclusions:Significant improvements in muscle conditioning and exercise performance are possible following the 13-week regimen of FES-LCE described in this article. Individuals with incomplete motor impairment experience greater improvements in mean power output than individuals with complete motor impairment.
