THE EFFECTS OF HYBRID FUNCTIONAL ELECTRICAL STIMULATION INTERVAL TRAINING ON AEROBIC FITNESS AND FATIGUE IN PEOPLE WITH ADVANCED MULTIPLE SCLEROSIS

Abstract

Improving aerobic fitness in people with multiple sclerosis (MS) can reduce fatigue, and lower the risk of cardiovascular disease. Aerobic training can be challenging due to paresis, access to suitable equipment and fatigue. The aim was to investigate whether functional electrical stimulation (FES) cycling combined with arm crank interval exercise (hybrid FES interval training) is feasible for people with advanced MS, and its effects on aerobic fitness and fatigue. Hybrid FES interval training was performed 2 d/wk for 12 weeks. Each session consisted of 40 minutes of continuous FES cycling with arm crank intervals of 30 seconds work/30 seconds rest added concurrently for 20 minutes. The intensity target was a minimum of 60% of arm crank power and ‘hard’ measured by rate of perceived exertion (RPE) on a scale of 6-20. Feasibility was measured by attendance, compliance to intensity and time targets, adverse events, and drop outs. Aerobic fitness was assessed by an arm crank maximal test. Fatigue was measured via the Modified Fatigue Impact Scale (MFIS). Seven participants (6 female; age 57.1±7.8y; Expanded Disability Status Scale 7.1±0.8) with advanced MS attended 80±10.4% of the scheduled sessions and there were no adverse events or drop outs. Average RPE at the end of each training session was 15±2, representing vigorous intensity exercise. Aerobic fitness did not change pre- to post-intervention [14.2±5.7 to 14.78±6.0 mL/kg/min (p=0.43)]. There was a trend towards a reduction in the MFIS score pre- to post-intervention [31.0±10.4 to 21.7±11.4 (p=0.10)]. Hybrid FES interval training is feasible for people with advanced MS who need exercise equipment appropriate for their condition, and can represent vigorous intensity exercise. The positive findings support the need for future randomized control trials that can assess the aerobic fitness changes and associated health benefits of hybrid FES interval training.