Aerobic walking in slowly progressive neuromuscular disease: Effect of a 12-week program

Objective: Poor cardiorespiratory endurance is a common finding in neuromuscular disease (NFAD), and the capacity of such patients to respond to aerobic training is unclear. This study was conducted to determine if a 12-week walking program results in increased aerobic capacity in slowly progressive NMD subjects, whether such a pro,sram is safely tolerated, and whether such patients can adhere to a self-monitored, home-based training program. Design: Before-after trial. Setting: Subjects' homes. Patients: A cohort of 8 slowly progressive NMD subjects (4 men, 4 women) followed in the neuromuscular disease clinic participated (age, 36.6 +/- 8.0yrs; ht, 170 +/- 11cm; wt, 74.3 +/- 19.0kg) (Mean +/- SD). Intervention: Subjects walked 15 to 30min 3 to 4 days a week at 50% to 60% of their heart rate reserve. Main Outcome Measures: Resting, submaximal, and peak heart rates, systolic and diastolic blood pressures, oxygen uptake, and peak power output. Results: Graded exercise testing to volitional fatigue using a semirecumbent cycle ergometer before and after the training program found significant decreases in submaximal heart rate by 7 +/- 3 beats/min (Mean +/- SEM) (95% CI = -23 to 9) (p = .046) and submaximal systolic blood pressure by 11 +/- 4mmHg (95% CI = -31 to 9) (p = .019), and nonsignificant increases in peak power output and VO2. Conclusions: These results suggest;hat moderate-intensity aerobic exercise training is well tolerated and may provide modest improvement in aerobic capacity in slowly progressive NMD subjects. (C) 1996 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation