# Body-weight supported treadmill or total body recumbent stepper for mobility-adapted cardiopulmonary exercise testing in multiple sclerosis patients with varying disability

## TL;DR

This study compares two exercise devices for testing heart and lung function in people with multiple sclerosis, finding that one device works better for those with mobility issues.

## Contribution

The study identifies the total body recumbent stepper as a more effective tool for maximal cardiopulmonary exercise testing in MS patients with mobility disability.

## Key findings

- MS patients achieved similar VO2max values on both devices, but controls performed better on the treadmill.
- MS patients more consistently met maximal CPET criteria using the total body recumbent stepper.
- The treadmill disadvantaged MS patients, especially those with mobility disability, compared to the stepper.

## Abstract

Accurate exercise prescription in persons with multiple sclerosis (MS) depends on cardiopulmonary exercise testing (CPET). Obtaining an accurate VO2max 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 V˙O2max, % normative values for V˙O2max (%V˙O2max), heart rate maximum (HRmax), age-predicted HRmax, and Respiratory Exchange Ratio.

MS patients, regardless of disability severity, achieved similar V˙O2max 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).

V˙O2max was similar between devices among MS patients. On BWST, they achieved lower V˙O2max 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.