Objective: To determine the effect of a resistive exercise program in the rehabilitation of patients with polymyositis/dermatomyositis (PM/DM).
Methods: Five patients participated in a rehabilitation program that included resistive exercises. In 4 of the patients, these exercises were randomly alternated with nonresistive exercise. Each type of exercise was assigned for periods of 2 weeks, and at the end of each one, muscle strength was measured by means of manual muscle testing (MMT), an activities of daily living (ADL) score, and peak isometric torque (PIT) generated by muscle groups in the lower extremities. Creatine phosphokinase (CPK) levels were used to measure disease activity. The acute response to resistive exercise was studied in 4 of the patients by measuring serial levels of CPK following a session on an exercise bicycle.
Results: Of the 4 patients who participated in both types of exercises, 3 experienced increases in strength during both resistive and nonresistive exercise periods. The patient who participated only in resistive exercises had considerable improvements in muscle strength. One patient made no improvements in strength with either type of exercise. None of the patients experienced clinically significant elevations in CPK attributable to either type of exercise. Following a session of resistive exercise, the mean CPK elevation in 4 patients was 7.7%, returning to pre-exercise levels by 8 h in all cases.
Conclusions: Patients with PM/DM may participate in a rehabilitation program which includes resistive exercises. Such programs may be accompanied by increased strength without clinically significant rises in serum levels of muscle enzymes.