Physical Activity and Sedentary Behavior From 6 to 11 Years

Area of Science:

• Pediatrics
• Child Development
• Public Health

Background:

• Physical activity (PA) is presumed to decline during childhood and adolescence.
• Limited long-term studies exist on PA development during this life stage.
• Understanding changes in PA and sedentary behavior (SB) is crucial for child health.

Purpose of the Study:

• To assess PA and SB changes over a 5-year period in children.
• To identify potential influencing factors on activity levels.
• To gain a better understanding of PA development from ages 6 to 11.

Main Methods:

• Objectively measured PA and SB in 600 children using SenseWear Armband 2.
• Data collected at ages 6, 8, and 11 years, totaling 1254 observations.
• Longitudinal changes modeled using mixed-effects models for total PA, MVPA, LPA, and SB.

Main Results:

• Total PA significantly declined by 75.3 minutes/day from ages 6-11.
• Light physical activity (LPA) linearly declined by 44.6 minutes/day.
• Moderate-to-vigorous physical activity (MVPA) quadratically declined by 30.7 minutes/day, while SB increased by 107 minutes.
• Boys exhibited steeper declines in LPA and MVPA compared to girls.
• Higher BMI z-scores and fat mass index correlated with lower PA and higher SB.

Conclusions:

• PA decreases and SB increases earlier than previously assumed.
• MVPA remained stable until age 8, then dropped significantly by age 11.
• Age 11 represents a critical period for targeted interventions to promote physical activity.