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Behavior Tracking and 3-Year Longitudinal Associations Between Physical Activity, Screen Time, and Fitness Among
Morgan Potter1, John C Spence1, Normand Boulé1
11 University of Alberta.
Insights
Physical activity (PA) and screen time (ST) are important for children's fitness development. Tracking PA and ST over time can help understand their impact on overall fitness in young children.
Area of Science:
- Pediatric Health
- Exercise Science
- Developmental Pediatrics
Background:
- Childhood fitness is crucial for long-term health.
- Understanding the factors influencing fitness development in children is essential.
Purpose of the Study:
- To investigate the longitudinal relationships between physical activity (PA), screen time (ST), and fitness in children.
- To determine if sex influences these associations.
- To track changes in PA and ST over a three-year period.
Main Methods:
- A cohort of 649 children (aged 4.5 years at baseline) from Edmonton, Canada, was studied over three years.
- Parental-reported weekly PA and ST were collected at baseline and follow-up.
- Fitness was assessed using multiple measures including grip strength and predicted VO2max; statistical analyses included regression models and Spearman correlations.
Main Results:
- Baseline screen time was negatively associated with follow-up grip strength.
- Baseline physical activity showed a significant positive association with overall fitness at follow-up and approached significance for VO2max.
- No significant sex interactions were found; moderate and large tracking were observed for PA and ST, respectively.
Conclusions:
- Physical activity and screen time are significant modifiable factors influencing overall fitness in young children.
- Longitudinal tracking of PA and ST provides insights into their developmental impact on fitness.
Purpose:
Understanding the correlates of children's fitness as they develop is needed. The objectives of this study were to 1) examine the longitudinal associations between physical activity (PA), screen time (ST), and fitness; 2) determine if sex moderates associations; and 3) track PA and ST over 3 years.
Methods:
Findings are based on 649 children [baseline = 4.5 (0.5) y; follow-up = 7.8 (0.6) y] from Edmonton, Canada. Parental-reported hour per week of PA and ST were measured at baseline and 3 years later. Fitness (vertical jump, sit and reach, waist circumference, grip strength, predicted VO2max, push-ups, and partial curl-ups) was measured using established protocols at follow-up. Sex-specific z scores or low/high fitness groups were calculated. Linear or logistic multiple regression models and Spearman correlations were conducted.
Results:
Baseline ST was negatively associated with follow-up grip strength [β = -0.010; 95% confidence interval (CI), -0.019 to -0.001]. Associations between baseline PA and follow-up overall fitness (β = 0.009; 95% CI, 0.002 to 0.016) were significant, whereas baseline PA and follow-up VO2max (β = 0.014; 95% CI, 0.000 to 0.027) approached significance (P < .06). No sex interactions were observed. Moderate and large tracking were observed for PA (rs = .30) and ST (rs = .53), respectively.
Conclusions:
PA and ST may be important modifiable correlates of overall fitness in young children.
