Increased aerobic fitness after neuromuscular electrical stimulation training in adults with spinal cord injury.

Abstract

To evaluate the efficacy of a novel neuromuscular electrical stimulation (NMES) system for improving aerobic fitness in individuals with spinal cord injury (SCI). It was hypothesized that training with this NMES system would increase peak oxygen consumption (Vo(2)peak) and peak heart rate (HRpeak) in a sedentary adult SCI population. Prospective cohort study. All testing took place at a university human performance laboratory. Volunteer participants with SCI (N=16; T4-11 American Spinal Injury Association Impairment Scale grades A and B) were recruited from the national SCI outpatient and outreach service databases. All completed the training program, but results from 2 participants were excluded because posttraining tests were invalid. Therefore, 14 participants (11 men, 3 women) completed the program and testing. Four electrodes (175cm(2)) were placed bilaterally on the quadriceps and hamstrings muscle groups, and subtetanic contractions were elicited using an NMES device. Training was undertaken unsupervised at home for 1 hour, 5d/wk for 8 weeks. An incremental treadmill wheelchair propulsion exercise test with simultaneous cardiopulmonary gas exchange analysis was used to determine Vo(2)peak and HRpeak. A statistically significant increase in Vo(2)peak (P=.001) and HRpeak (P=.032) between baseline and follow-up was observed. This novel form of NMES is an effective method of improving aerobic fitness in an SCI population. Results are comparable to those with current functional electrical stimulation exercise systems.