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Updated: May 15, 2026
Assessment of Child Anthropometry in a Large Epidemiologic Study
Published on: February 2, 2017
Association between objectively measured sedentary behavior and body mass index in preschool children
1Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA. byun@email.sc.edu
Insights
Sedentary behavior in preschool children, measured by accelerometry, showed no independent link to body mass index (BMI) z-scores. This finding held true across different measurement cutpoints and after accounting for physical activity levels.
Area of Science:
- Pediatric Health
- Obesity Research
- Physical Activity Measurement
Background:
- Childhood obesity is a significant public health concern.
- Understanding factors influencing body mass index (BMI) in preschoolers is crucial.
- Sedentary behavior is increasingly prevalent in early childhood.
Purpose of the Study:
- To investigate the association between accelerometry-derived sedentary behavior and BMI z-score in preschool children.
- To examine if different accelerometry cutpoints for sedentary behavior alter this association.
Main Methods:
- Cross-sectional analysis of data from two preschool studies (CHAMPS and EDPAPC).
- Included 418 preschool children (ages 3-5) with complete accelerometry and BMI z-score data.
- Linear mixed regression models assessed sedentary behavior (using three cutpoints) and BMI z-score, adjusting for covariates including moderate-to-vigorous physical activity (MVPA).
Main Results:
- No independent association was found between sedentary behavior and BMI z-score in either study sample.
- This null association persisted even when applying different accelerometry cutpoints for sedentary behavior.
- The relationship remained non-significant after adjusting for MVPA and other covariates.
Conclusions:
- Accelerometry-derived sedentary behavior is not independently associated with BMI z-score in preschool children, irrespective of the cutpoint used.
- Further longitudinal research is recommended to explore potential long-term associations.
- Current findings suggest that physical activity levels may be a more critical factor than sedentary time alone in this age group.
Objective:
To determine the association between accelerometry-derived sedentary behavior and body mass index (BMI) z-score in preschool children, and to determine whether the association changed when applying three different accelerometry cutpoints for sedentary behavior.
Design And Subjects:
Cross-sectional design. Data came from two completed studies: Children's Activity and Movement in Preschool Study (CHAMPS) and the Environmental Determinants of Physical Activity in Preschool Children (EDPAPC) study. Children of ages 3-5 years with complete data on sedentary behavior, BMI z-score, physical activity and other covariates were included in the analyses (N=263 in CHAMPS and N=155 in EDPAPC). Accelerometry data were summarized as time spent in sedentary behavior (min h(-1)) using three different cutpoints developed specifically for preschool children (<37.5, <200 and <373 counts per 15 s). Linear mixed regression models were used to determine the association between time spent in sedentary behavior and BMI z-score; age, gender, race, parental education, preschools and moderate-to-vigorous physical activity (MVPA) were included as covariates.
Results:
In both CHAMPS and EDPAPC studies, no independent association between time spent in sedentary behavior and BMI z-score was observed after adjusting for MVPA. The observed null association between sedentary behavior and BMI z-score was maintained even with different sedentary behavior cutpoints.
Conclusions:
Regardless of cutpoints used, accelerometry-derived sedentary behavior was not independently associated with BMI z-score in two independent samples of preschool children. Longitudinal studies addressing this research question are needed.
