10-meter Walk Test Predicts Cardiorespiratory Fitness In People Moderately Affected By Stroke

In people mildly affected by stroke, walking endurance, measured via the 6-minuite walk test (6MWT), could help predict cardiorespiratory fitness or V̇O2 peak. However, in people moderately affected by stroke, the prediction of V̇O2 peak using 6MWT may be limited due to motor weakness rather than cardiorespiratory endurance. It is also largely underexplored whether a shorter functional walking test such as the 10-meter walk test (10MWT) can contribute to the prediction of V̇O2 peak. PURPOSE: To determine if 10MWT and 6MWT improves the prediction of V̇O2 peak in moderately affected stroke survivors. We hypothesized that in addition to age, sex, and body weight, the maximum walking speed (MWS) measured during the 10MWT and the distance covered during the 6MWT will contribute to the prediction of V̇O2 peak in people moderately affected by stroke. METHODS: Thirty-three moderately affected stroke survivors (≥ 6 months post stroke, 22 females, 61 ± 12 years, Fugl-Meyer lower extremity motor score: 24 ± 5) were enrolled. At the first visit, 10MWT and 6MWT were performed. At the second visit, participants completed a graded exercise test to measure V̇O2 peak using a recumbent bike and a metabolic cart. Participants started pedaling at 10 Watts (W) and the workload was increased by 15 W every 2 minutes until: (1) volitional fatigue, (2) V̇O2 plateau, (3) cadence <40 rpm, or (4) an adverse response to exercise. Measurements of exhaled gases were averaged every 30 seconds and V̇O2 peak was defined as the highest 30-second value. A stepwise multiple regression model with 5 variables (age, sex, body weight, MWS, and 6MWT distance) was calculated to predict V̇O2 peak. RESULTS: In moderately affected stroke survivors, V̇O2 peak could be predicted with 68% shared variance (V̇O2 peak (mL/kg/min) = 30.71 + 4.24 × MWS (m/s) - 0.16 × age (year) - 0.13 × body weight (kg) + 3.98 × sex (0 = f; 1 = m), p < 0.001). The 6MWT distance was not significant in the V̇O2 peak prediction model. CONCLUSIONS: MWS added significant value in predicting V̇O2 peak in moderately affected stroke survivors, in combination with age, body weight, and sex. Our results suggest that MWS may be a stronger predictor for V̇O2 peak than the 6MWT distance in people moderately affected by stroke. The 10MWT may be a quick test to clinically predict V̇O2 peak in moderately affected stroke survivors. Eunice Kennedy Shriver National Institute of Child Health and Human Development R01 Grant (HD099340, ASH & MJD) and American Heart Association Predoctoral Fellowship (903373, ZZ)