Benefits of Functional Electrical Stimulation Cycling in People with Mobility Restrictions Due to MS

Background: People with MS and EDSS scores of 6 or greater experience deconditioning resulting from the impairments caused by MS, as well as their restricted mobility. Decreased physical activity can progress ones disability, and increases the risk of secondary health conditions. Emerging evidence suggests that exercise is safe and beneficial for people with MS. However, those who are limited to a wheelchair for mobility are the most understudied in this regard, and face the most barriers to exercise. Functional electrical stimulation (FES) cycling is of interest because people with significant weakness and mobility challenges can use this intervention to activate leg muscles, which may provide enough exercise to induce changes in health measures, and decrease disability. 

Objectives: To evaluate safety, as well as the potential for FES cycling to improve fatigue, pain, spasticity and perceived quality of life, in people with moderate to severe MS.  

Methods: In this IRB-approved pilot study, we recruited 16 people with MS and EDSS scores ≥ 6.0. Participants trained on the RT-300 FES cycle (Restorative Therapies, Inc., Baltimore, MD) 2-3 times a week for approximately one month. The goal was to cycle at 35-50 rpm for 30 minutes, either actively or with electrical stimulation for assist. Intensity of FES was adjusted for each participant based on comfort. Data collected immediately before and after the 4-week training period included: MS Quality of Life Inventory (MS QLI) subscales, Modified Ashworth Scale (MAS, spasticity), and manual muscle test (MMT, strength). Data was also collected at each training session to monitor progress on the cycle, and for any changes in status. 

Results: Fourteen participants (6 female, 8 male) with MS completed the training. All participants were able to either maintain or increase the amount of time they could cycle; half (7/14) were able to increase the resistance against which they cycled. Participants demonstrated a significant increase in cognitive processing speed (PASAT; p<0.001), and a significant decrease in pain (MOS Pain Effects Scale; p<0.02). There was no significant change in the other subscales of the MS QLI. There was neither a significant increase nor decrease in MAS and MMT scores. The type of MS (i.e., relapse-remitting, secondary progressive or primary progressive), and the use of anti-spasticity medications, disease modifying therapies, or Ampyra or 4-aminopyridine, did not appear to influence the response to training. There were no adverse events, or worsening of MS symptoms. 

Conclusions: FES cycling may be a viable and effective option of exercise for people with moderate to severe MS. Further study is required to examine the parameters of FES cycling that are most effective for people with different constellations of MS symptoms, and to fully explore the potential benefits for optimizing function and improving health in people with MS.