The Role of Moderate Aerobic Exercise as Determined by Cardiopulmonary Exercise Testing in ALS

INTRODUCTION: The efficacy of cardiopulmonary exercise testing (CPET) to determining exercise intensity has not been established in Amyotrophic Lateral Sclerosis (ALS). We studied this intervention. METHODS: We included 48 ALS patients randomized in 2 groups: G1 (n = 24), exercise intensity leveled by CPET; G2 (n = 24), standard care limited by fatigue, during 6 months. ALS functional scale (ALSFRS-R) and forced vital capacity (FVC) were performed every 3 months; CPET was done at admission (T1) and 6 months later (T2). We registered oxygen uptake, carbon dioxide output, and ventilation at anaerobic threshold and at peak effort. Primary outcome was functional change. We used parametric statistics for comparisons and multiple regression analyses to identify independent predictors of functional decline. RESULTS: At T1 both groups were identical, except for higher FVC in G1 (p = 0.02). At T2, ALSFRS-R was higher (p = 0.035) in G1. Gas exchange variables at T2 did not change in G1 but had significant differences in G2 (p < 0.05). Multiregression analyses showed the Spinal ALSFRS-R slope and Intervention group (p < 0.001) as significant predictors of ALSFRS-R at T2. CONCLUSION: Aerobic exercise defined by CPET is feasible and can improve functional outcome in ALS. This trial is registered with Clinical trials.gov ID: NCT03326622.