Volume 41 Number
6A, November/December 2004
Pages 787 — 796
Effects of stimulation pattern on electrical stimulation-induced leg cycling
Thomas W. J. Janssen, PhD, FACSM; Maaike Bakker, MSc; Annick Wyngaert, MSc; Karin (H. L.) Gerrits, PhD; Arnold de Haan, PhD
Institute for Fundamental and Clinical Human Movement Sciences and Faculty of Human Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands; Rehabilitation Center Amsterdam, Amsterdam, The Netherlands; Institute for Biophysical and Clinical Research into Human Movement, Manchester Metropolitan University, Alsager Campus, United Kingdom
Abstract — Electrical stimulation-induced leg cycling (ES-LC) is beneficial for individuals with spinal cord injury (SCI), but cycling performance is often limited because of rapid fatigue of the stimulated muscles. This study evaluated whether a stimulation pattern with a catchlike-inducing pulse train increased force production and hence cycling performance. Five men with SCI performed ES-LC using different stimulation patterns: (1) the standard pattern with ramp modulation, (2) a pattern with no ramp modulation, (3) a pattern with no ramp modulation but with an initial doublet, and (4) a pattern with a middle doublet. None of the experimental patterns resulted in significantly improved cycling performance compared with the standard pattern. However, during the first 3 min of cycling, the current amplitude was significantly higher with the standard stimulation, suggesting that stimulation with no ramp modulation produces more force at the same submaximal current amplitude. The results do not indicate that stimulation with catchlike-inducing trains with the current parameter settings improves ES-LC performance.
Key words: catchlike property, electrical stimulation, exercise, fatigue, paraplegia, spinal cord injury, tetraplegia.