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Updated: Sep 28, 2026
Assessment of Child Anthropometry in a Large Epidemiologic Study
Published on: February 2, 2017
Fatness, physical activity, and television viewing in children during the adiposity rebound period: the Iowa Bone
Kathleen F Janz1, Steven M Levy, Trudy L Burns
1Department of Health and Sport Studies, 102 FH, The University of Iowa, Iowa City, IA 52242, USA. kathleen-janz@uiowa.edu
Insights
Low vigorous physical activity and high TV viewing in young children are linked to increased body fat. Promoting active play may help prevent childhood obesity and future health issues.
Area of Science:
- Pediatrics
- Obesity Research
- Child Development
Background:
- Childhood adiposity is a critical determinant of adult obesity.
- The adiposity rebound period (ages 4-6) is inversely associated with later obesity.
- Understanding early life factors influencing adiposity is crucial for prevention.
Purpose of the Study:
- To examine the cross-sectional associations between physical activity, TV viewing, and adiposity in young children.
- To identify key behavioral determinants of body fatness during the adiposity rebound period.
Main Methods:
- Study included 467 children aged 4-6 years.
- Physical activity was measured using accelerometry and parental TV viewing reports.
- Body composition was quantified using dual-energy X-ray absorptiometry.
Main Results:
- Vigorous physical activity and TV viewing were significantly associated with adiposity.
- Children with the least vigorous activity had 4% higher body fat percentages.
- Children with the most TV viewing had 3% higher body fat percentages.
Conclusions:
- Low vigorous physical activity and high TV viewing are linked to increased fatness in young children.
- Interventions promoting active play may be vital for preventing childhood and adult obesity.
Background:
Understanding the determinants of adiposity in young children may be particularly critical for preventing adult obesity since the age at which body fatness reaches a postinfancy low point (typically 4-6 years) is inversely associated with obesity later in life. METHODS; We examined cross-sectional associations among fatness, leanness, and physical activity in 467 children (range 4-6 years). Activity was measured using accelerometry and parental report of children's television (TV) viewing. Dual energy X-ray absorptiometry was used to quantify body composition.
Results:
Minutes spent in vigorous activity and TV viewing were the variables most consistently and most highly associated with adiposity. Children in the lowest quartile for vigorous activity had on average (absolute) body fat percentages that were 4% greater than those children in the highest quartile for vigorous activity. Body fat percentages for children in the highest category for TV viewing were on average 3% greater than those children who watched the least amount of TV.
Conclusions:
Low levels of vigorous physical activity and high levels of TV viewing are associated with fatness in young children during the adiposity rebound period. This suggests that increasing children's active play may be important in preventing obesity later in life.
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