RESUMO
OBJECTIVES: To evaluate the feasibility, safety and efficacy of exercise training in patients with immune-mediated necrotising myopathies (IMNM). METHODS: Eight consecutive sedentary patients with IMNM (5 anti-signal recognition particle and 3 anti-hydroxy-methyl-glutaryl coenzyme A reductase) were engaged in this study. Disease status was based on International Myositis Assessment and Clinical Studies Group (IMACS) core set measures. Physical performance was evaluated by cardiopulmonary exercise test, repetition maximum (RM) protocol, handgrip dynamometry, sit-to-stand (STS) and timed up-and-go (TUG) tests. All these parameters were measured at baseline and after a 12-week, twice-a-week, supervised exercise training comprising aerobic and strength exercises. RESULTS: Patients (aged 61 years on average) were very disabled at the beginning of the disease (mean duration of 17.7 months), but after being aggressively treated with a treat-to-target approach, they presented only mild symptoms that were well-controlled with oral immunosuppression and low disease status scores by the time of the exercise intervention. No disease relapsing, worsening of the IMACS set scores or adverse events were observed throughout the training period. Patients also increased aerobic capacity (e.g. time to achieve anaerobic threshold and time to achieve exhaustion), muscle strength (e.g. 1RM bench press) and function (e.g. STS test). CONCLUSIONS: Supervised exercise training did not impair disease status and seemed to be feasible, safe and effective in patients with IMNM. Moreover, exercise training increased aerobic capacity, muscle strength and function, suggesting that this could be a novel potential coadjuvant therapy in IMNM.