The Right Tool for the Task: Body-Weight Supported Treadmill or Total Body Recumbent Stepper for Mobility-Adapted Cardiopulmonary Exercise Testing in Multiple Sclerosis Patients with Disability

ObjectiveCardiopulmonary Exercise Testing (CPET) is challenging among persons with mobility disability. We sought the optimal adapted device to achieve a maximal CPET. DesignRandomized crossover trial, within-subjects, repeated measures design SettingPrimary Care and Referral Center ParticipantsClinic-referred persons with multiple sclerosis (PwMS) (n=10) with three-month stability, no exercise obstruction, MoCa>24, ability to walk with or without assistance, and sex- and age-matched ({+/-}3 years) Controls (n=7) recruited by convenience sampling InterventionsCPET on body weight-supported treadmill (BWST) and total body recumbent stepper (TBRS) Main Outcome MeasuresStandard aerobic metrics ([V]O2max, % normative values for [V]O2max [%[V]O2max], heart rate maximum [HRmax], age-predicted HRmax, and Respiratory Exchange Ratio) ResultsPwMS achieved similar [V]O2max (mL{middle dot}min-1{middle dot}kg-1) on the TBRS and BWST (26.53{+/-}8.7 vs. 24.24{+/-}7.8) while Controls obtained higher values on BWST than TBRS (40.27{+/-}7.6 vs. 34.32{+/-}7.1, p<0.001). PwMS more consistently achieved criteria for maximum CPET using TBRS. During the preliminary investigation of the MS subgroup with a higher mobility disability, CPET using BWST exaggerated already low CPET metrics. ConclusionsAlthough Controls achieved higher CPET values on BWST, [V]O2max between devices were similar among PwMS. Only when using BWST, PwMS [V]O2max and %[V]O2max were lower than Controls, likely because of leg fatigue and weakness. Using TBRS permits persons with mobility disability to achieve more criteria for a maximum CPET. Our results suggest that CPET using BWST, being reliant on the lower body, likely disadvantages PwMS, especially those with mobility disability.