The effects of proprioceptive neuromuscular facilitation exercises on fatigue, muscle strength and functional parameters in patients with myasthenia gravis

The aim of this study was to investigate the effects and feasibility of the Proprioceptive Neuromuscular Facilitation (PNF) training in patients with Myasthenia Gravis (MG). A randomized controlled and single-blind study design was used, with participants divided into two groups: a PNF group (n=10) and a control group (n=10). Individuals in the PNF group performed PNF training for 6 weeks, three times a week on alternate days, with each session lasting 60 minutes. During the same period, the control group continued their routine daily activities and were placed on a waiting list for treatment. All participants were assessed twice, at the beginning and at the end of the trial. The effects of the PNF training were assessed on several parameters, including perceived fatigue (Fatigue Severity Scale (FSS), Chalder Fatigue Scale (CFS), and Fatigue Impact Scale (FIS)), muscle fatigability (median frequency analysis using surface electromyography and linear trend obtained from the six-minute walk test), muscle strength (digital dynamometer), functional capacity (thirty-second sit-to-stand test (TS-STS), ten-step stair climb test (TS-SCT), and six-minute walk test (SMWT)), activities of daily living (MG Activities of Daily Living Scale (MG-ADL)), quality of life (MG Quality of Life Scale (MG-QOL)), and disease severity (MG Composite Scale (MGCS)). In addition, the feasibility and tolerability of the PNF training in patients with MG were evaluated (Visual Analog Scale). The results showed statistically significant improvements in perceived fatigue (FSS, p=0.02; CFS, p=0.004; FIS, p=0.004), functional capacity (TS-STS, p=0.007; TS-SCT, p=0.029; SMWT, p=0.047), functional status in activities of daily living (MG-ADL, p=0.002), quality of life (MG-QOL, p=0.003), and disease severity (MGCS, p=0.002) with the PNF training. Additionally, PNF training was found to be safe, feasible, and tolerable for patients with MG. While some variables related to muscle fatigability and muscle strength showed statistically significant (p>0.05) and positive effects; others showed no significant differences (p<0.05). In conclusion, the effectiveness of PNF training on perceived fatigue and muscle fatigability, which are the most challenging symptoms of MG, has been extensively demonstrated using objective assessments. Positive effects on muscle strength and functional parameters were also observed. We believe that this study will provide guidance for the development of exercise guidelines and future research in patients with MG.