Ratings of Perceived Exertion During Walking: Predicting Major Mobility Disability and Effect of Structured Physical...

This study evaluated the association between ratings of perceived exertion (RPE) of walking and major mobility disability (MMD), as well as their transitions in response to a physical activity (PA) compared to a health education (HE) program.

Older adults (n = 1633) who were at risk for mobility impairment were randomized to structured PA or HE programs. During a 400 m walk, participants rated exertion as "light" or "hard." An MMD event was defined as the inability to walk 400 m. MMD events and RPE values were assessed every 6 months for an average of 2.6 years.

Participants rating their exertion as "hard" had a nearly threefold higher risk of MMD compared with those rating their exertion as "light" (HR: 2.61, 95% CI: 2.19-3.11). The association was held after adjusting for disease conditions, depression, cognitive function, and walking speed (HR: 2.24, 95% CI: 1.87-2.69). The PA group was 25% more likely to transition from "light" to "hard" RPE than the HE group (HR: 1.25, 95% CI: 1.05-1.49). Additionally, the PA group was 27% (HR: 0.73, 95% CI: 0.55 - 0.97) less likely to transition from a "hard" RPE to inability to walk 400 m and was more likely to recover their ability to walk 400 m by transitioning to a "hard" RPE (HR: 2.10, 95% CI: 1.39-3.17) than the HE group.

Older adults rating "hard" effort during a standardized walk test were at increased risk of subsequent MMD. A structured PA program enabled walking recovery, but was more likely to increase transition from "light" to "hard" effort, which may reflect the greater capacity to perform the test.