Effects of change in physical activity on physical function limitations in older women: mediating roles of physical function performance and self-efficacy.
OBJECTIVE
To examine the hypothesis that changes in self-efficacy and functional performance mediate, in part, the beneficial effect of physical activity on functional limitations over time.


METHODS
Prospective, observational study.


METHODS
Community-based.


METHODS
Two hundred forty-nine community-dwelling older women.


METHODS
Participants completed measures of self-reported physical activity, functional limitations, and self-efficacy. Four measures of physical function performance were also assessed. Measures were completed at baseline and 24 months. Data were analyzed using a panel model within a covariance modeling framework.


RESULTS
Results indicated that increases in physical activity over time were associated with greater improvements in self-efficacy, which was associated in turn with improved physical function performance, both of which mediated the association between physical activity and functional limitations. Fewer functional limitations at baseline were also associated with higher levels of self-efficacy at 24 months. Age, race, and health status covariates did not significantly change these relationships.


CONCLUSIONS
The findings support the mediating roles of self-efficacy and physical function performance in the relationship between longitudinal changes in physical activity and functional limitations in older women.
McAuley
Edward
E
Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801, USA. emcauley@uiuc.edu
Morris
Katherine S
KS
Doerksen
Shawna E
SE
Motl
Robert W
RW
Liang
Hu
H
White
Siobhan M
SM
Wójcicki
Thomas R
TR
Rosengren
Karl
K
D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D006233:Persons with Disabilities / Q000523:psychology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D051346:Mobility Limitation; D009043:Motor Activity; D011446:Prospective Studies; D020377:Self Efficacy; D011795:Surveys and Questionnaires