Body-weight supported treadmill or total body recumbent stepper for mobility-adapted cardiopulmonary exercise testing...

Accurate exercise prescription in persons with multiple sclerosis (MS) depends on cardiopulmonary exercise testing (CPET). Obtaining an accurate VO_2max can be challenging when patients experience lower limb impairment and fatigue that can change over time.

We sought the optimal adapted device to achieve a maximal CPET among persons with MS.

In a randomized crossover trial with within-subject, repeated measures design, clinic-referred persons with MS (n = 10) with three-month stability, no exercise obstruction, ability to walk with or without assistance, and sex- and age-matched (±3 years) Controls (n = 7) were recruited by convenience sampling. Participants performed CPET on body weight-supported treadmill (BWST) and total body recumbent stepper (TBRS). We collected standard aerobic metrics, including $\dot{V}{O}_{2max}$ , % normative values for $\dot{V}{O}_{2max}$ (% $\dot{V}{O}_{2max}$ ), heart rate maximum (HR_max), age-predicted HR_max, and Respiratory Exchange Ratio.

MS patients, regardless of disability severity, achieved similar $\dot{V}{O}_{2max}$ values (mL·min^-1·kg^-1) on the TBRS and BWST. Control participants obtained higher values on BWST (40.27 ± 7.6 vs. 34.32 ± 7.1, p < 0.001). MS patients more consistently met the criteria for maximal CPET using the TBRS (n = 9/10 vs. 6/10 on BWST).

$\dot{V}{O}_{2max}$ was similar between devices among MS patients. On BWST, they achieved lower $\dot{V}{O}_{2max}$ values compared to Controls. MS patients more successfully achieved the primary criterion, VO₂ plateau (≤150 ml/min^-1), using TBRS. Additionally, TBRS permitted 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 MS patients, especially those with mobility disability.