Physical activity and bone measures in young children: the Iowa bone development study

Area of Science:

• Pediatric bone health
• Childhood physical activity
• Growth and development

Background:

• Physical activity benefits bone development in older children.
• The impact of physical activity on bone health in younger children remains less understood.
• Early childhood is a critical period for establishing foundational bone mass.

Purpose of the Study:

• To investigate the association between physical activity and bone measures in preschool children.
• To determine if different measures of physical activity correlate with bone mineral content and density.
• To explore the relationship between sedentary behavior (television viewing) and bone health in this age group.

Main Methods:

• Cross-sectional study of 368 preschool children (ages 4-6).
• Physical activity assessed via accelerometry and parental reports.
• Bone mineral content and bone mineral density (BMD) measured using dual-energy X-ray absorptiometry.

Main Results:

• Physical activity, measured by accelerometry and parental report, showed consistent positive associations with bone mineral content and BMD in both boys and girls.
• Higher levels of vigorous physical activity and overall reported activity were significant predictors of better bone measures.
• Television viewing was inversely associated with hip bone mineral density in girls.

Conclusions:

• Significant associations exist between physical activity and bone measures in early childhood.
• These findings suggest that interventions promoting physical activity in young children can positively impact bone development.
• Early physical activity may contribute to achieving optimal peak bone mass later in life.