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Published on: April 19, 2017
Physical Activity Patterns and Correlates of 9-Month-Old Chinese Infants in the Macau Population
Zhenzhen Jia1, Joni Zhang2, Dulce Trindade3,4
1Faculty of Science, School of Biological Sciences, The University of Hong Kong, 6F, Kadoorie Biological Sciences Building, Pokfulam, Hong Kong.
Insights
This study found that 9-month-old infants have more screen time on weekdays and their physical activity (PA) correlates with maternal PA and BMI. Early, time-specific interventions are recommended for infant PA promotion.
Area of Science:
- Pediatrics
- Public Health
- Child Development
Background:
- Childhood habits significantly influence obesity-related chronic diseases.
- Understanding infant physical activity (PA) is crucial for effective intervention programs.
Purpose of the Study:
- To describe the physical activity (PA) levels and patterns of 9-month-old infants.
- To examine correlates of infant PA, including maternal factors and time of day.
Main Methods:
- 143 infant-mother dyads in Macau participated.
- Physical activity (PA) was measured using accelerometers (Actigraph GT3X+).
- Demographic data and maternal BMI were collected via questionnaires.
Main Results:
- Infants exhibited higher screen time on weekdays.
- Infant and maternal activity levels peaked in the evening and were lowest in the morning.
- Infant PA correlated with maternal PA intensity on weekends and was predicted by maternal BMI.
Conclusions:
- Physical activity promotion programs for infants should incorporate time-specific strategies.
- This research provides foundational data on 9-month-old infants' PA in Macau.
- Findings can inform future healthy lifestyle interventions for infants in the region.
Abstract:
Objectives Many obesity-related chronic diseases originate from unhealthy childhood habits. The aim of this study was to describe 9-month-old infants' physical activity levels and patterns and to examine the correlates. Understanding these factors is necessary for improving the effectiveness of physical activity intervention programs for infants. Methods In total, 143 infant-mother dyads from Macau, SAR China, participated in this study. Physical activity (PA) was assessed by using the Actigraph GT3X+ accelerometer and the demographic variables were collected by questionnaires. Results The most important findings were that: (1) infants had more screen time during weekdays (p = .044); (2) infants and mothers were least active at 8 a.m. (both weekdays and weekends) in the morning and most active at 7 p.m. (weekdays) and 8 p.m. (weekends) in the evening; (3) infants' PA levels significantly correlated with their mothers' PA intensities during the weekends (r = .192, p = .036), especially the mothers' lower intensities in the mornings and evenings; (4) maternal BMI predicted the PA levels of the 9-month-old infants' (R2 = .06, β = 29.188, p = .009). Conclusions for Practice Physical activity promotion programs for infants should be time-specific starting from early infancy. This study was one of the first to examine 9-month-old infants' PA levels, patterns and correlates. The results may be helpful in improving the effectiveness of future healthy lifestyle intervention programs for infants in Macau and in the region in general.
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