Suggested Citation:
Hakansson, Nils A. and Maury L. Hull (2011)

Can the Efficacy of Electrically Stimulated Pedaling Using a Commercially Available Ergometer Be Improved by Minimizing the Muscle Stress–Time Integral?

Introduction: The cardiorespiratory and muscular strength benefits of functional electrical stimulation (FES) pedaling for spinal cord injury (SCI) subjects are limited because the endurance of electrically stimulated muscle is low. Methods: We tested new electrical stimulation timing patterns (Stim3, designed using a forward dynamic simulation to minimize the muscle stress–time integral) to determine whether SCI subjects could increase work and metabolic responses when pedaling a commercial FES ergometer. Work, rate of oxygen uptake (V̇O2), and blood lactate data were taken from 11 subjects (injury level T4–T12) on repeated trials. Results: Subjects performed 11% more work pedaling with Stim3 than with existing stimulation patterns (StimErg) (P = 0.043). Average (V̇O2) and blood lactate concentrations were not significantly different between Stim3 (442 ml/min, 5.9 mmol/L) and StimErg (417 ml/min, 5.9 mmol/L). Conclusion: The increased mechanical work performed with Stim3 supports the use of patterns that minimize the muscle stress–time integral to prolong FES pedaling. Muscle Nerve, 2012