Background: It is not well understood how sedentary women who wish to engage in regular exercise adhere to interventions during pregnancy and what factors may influence adherence over time.
Objective: The aim of this study was to examine longitudinal patterns of pregnant women's adherence to exercise.
Methods: Exploratory secondary data analyses were carried out with 124 previously sedentary pregnant women (ages 31 ± 5 years; 85% non-Hispanic White) from a randomized controlled trial. Daily exercise logs (n = 92) from 18 through 35 weeks of gestation were explored using linear regression, functional data, and principal component analyses.
Results: Adherence decreased as gestation week increased (p < .001). The top adherers maintained levels of adherence, and the bottom adherers decreased levels of adherence. And adherence pattern was influenced by types of exercise throughout the study period.
Discussion: Exercise behavior patterns were explored in a randomized controlled trial study, using chronometric data on exercise attendance. A new analytic approach revealed that sedentary pregnant women may adopt exercise habits differently from other populations.
SeonAe Yeo, RCN, PhD, FAAN, is Associate Professor of Nursing, School of Nursing; Jessi Cisewski, is PhD Candidate, Department of Statistics and Operation Research; Eric F. Lock, is PhD Candidate, Department of Statistics and Operation Research; and J. S. Marron, PhD, is Amos Hawley Professor of Statistics and Operations Research and Professor of Biostatistics, Departments of Statistics and Operation Research and Biostatistics, University of North Carolina at Chapel Hill.
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Accepted for publication January 11, 2009.
This study was supported by National Institutes of Health Grant R01-NR05002.
Corresponding author: SeonAe Yeo, RCN, PhD, FAAN, School of Nursing, University of North Carolina at Chapel Hill, Carrington Hall, Campus Box 7460, Chapel Hill, NC 27599-7460 (e-mail: email@example.com).