Effects of Whole-body Electrical Muscle Stimulation Exercise on Adults With Myasthenia Gravis
During this pilot study, the investigators will examine the effects of whole-body electrical muscle stimulation exercise (WB-EMS Exercise) on neuromuscular junction (NMJ) transmission and fatigability in adults with Generalized Myasthenia Gravis (gMG). The investigators will also test whether a relationship exists between NMJ transmission dysfunction and fatigability in gMG, which has long been presumed but never directly assessed. Participants will undergo clinical and electrophysiologic testing before and after the WB-EMS Exercise intervention. The WB-EMS Exercise intervention will be delivered 2 times per week for 4 weeks. Long-term follow up is optional. The hypotheses are (a) that the WB-EMS exercise will improve fatigability and NMJ transmission, and (b) that NMJ transmission dysfunction is related to fatigability.
• Age 18 or older
• Diagnosed with Generalized Myasthenia Gravis (gMG) via seropositive test for acetylcholine receptor (AChR) antibodies or seronegative test with clinical symptoms consistent with gMG
• On stable MG therapy for at least 1 month
• Ability to stand for approximately 15 minutes continuously with or without an assistive device (i.e. the length of time to stand to take a shower, complete meal preparation, wait in line at the bank, etc.)
• Score of 1 (Mild) or 2 (Moderate) on at least one side of the arm outstretched and leg outstretched items of the QMG, demonstrating fatigability
• At least some anti-gravity strength in major muscle groups as assessed by manual muscle testing (i.e. 2+/5 strength or better)
• Medical clearance to participate in an exercise program
• Ability to provide informed consent
• Ability to conform to the requirements of the study (i.e. attendance at assessment and intervention visits, maintain current level of non-study physical activity for the duration of the study, no intention to relocate mid-study)
• Age 18-39 years
• Ability to provide informed consent