Physical Activity Minimum Threshold Predicting Improved Function in Adults With Lower‐Extremity Symptoms

Authors

Dorothy D. Dunlop, Northwestern University
Jing Song, Northwestern University
Jungwha Lee, Northwestern University
Abigail L. Gilbert, Northwestern UniversityFollow
Pamela A. Semanik, Rush UniversityFollow
Linda S. Ehrlich-Jones, Shirley Ryan AbilityLab
Christine A. Pellegrini, Northwestern UniversityFollow
Daniel Pinto, Marquette UniversityFollow
Barbara Ainsworth, Arizona State University
Rowland W. Chang, Northwestern UniversityFollow

Document Type

Article

Language

eng

Publication Date

4-2017

Publisher

American College of Rheumatology

Source Publication

Arthritis Care & Research

Source ISSN

2151-464X

Abstract

Objective

To identify an evidence‐based minimum physical activity threshold to predict improved or sustained high function for adults with lower‐extremity joint symptoms.

Methods

Prospective multisite data from 1,629 adults, age ≥49 years with symptomatic lower‐extremity joint pain/aching/stiffness, participating in the Osteoarthritis Initiative accelerometer monitoring substudy were clinically assessed 2 years apart. Improved/high function in 2‐year gait speed and patient‐reported outcomes (PROs) were based on improving or remaining in the best (i.e., maintaining high) function quintile compared to baseline status. Optimal thresholds predicting improved/high function were investigated using classification trees for the legacy federal guideline metric requiring 150 minutes/week of moderate‐vigorous (MV) activity in bouts lasting 10 minutes or more (MV‐bout) and other metrics (total MV, sedentary, light intensity activity, nonsedentary minutes/week).

Results

Optimal thresholds based on total MV minutes/week predicted improved/high function outcomes more strongly than the legacy or other investigated metrics. Meeting the 45 total MV minutes/week threshold had increased relative risk (RR) for improved/high function (gait speed RR 1.8, 95% confidence interval [95% CI] 1.6, 2.1 and PRO physical function RR 1.4, 95% CI 1.3, 1.6) compared to less active adults. Thresholds were consistent across sex, body mass index, knee osteoarthritis status, and age.

Conclusion

These results supported a physical activity minimum threshold of 45 total MV minutes/week to promote improved or sustained high function for adults with lower‐extremity joint symptoms. This evidence‐based threshold is less rigorous than federal guidelines (≥150 MV‐bout minutes/week) and provides an intermediate goal towards the federal guideline for adults with lower‐extremity symptoms.

Comments

Accepted version. Arthritis Care & Research, Vol. 69, No. 4 (April 2017): 475-483. DOI. © 2017 John Wiley & Sons, Inc. Used with permission.

Daniel Pinto was affiliated with Northwestern University at the time of publication.

Recommended Citation

Dunlop, Dorothy D.; Song, Jing; Lee, Jungwha; Gilbert, Abigail L.; Semanik, Pamela A.; Ehrlich-Jones, Linda S.; Pellegrini, Christine A.; Pinto, Daniel; Ainsworth, Barbara; and Chang, Rowland W., "Physical Activity Minimum Threshold Predicting Improved Function in Adults With Lower‐Extremity Symptoms" (2017). Physical Therapy Faculty Research and Publications. 155.
https://epublications.marquette.edu/phys_therapy_fac/155