Background The prevalence of obesity in children and adolescents remains a global public health issue. Wearable devices may offer new opportunities for prevention and intervention in obesity. Previous systematic reviews have only examined the effect of the wearable device interventions on preventing and treating obesity in adults. However, no systematic review has provided an evaluation of wearable devices as physical activity interventions for preventing and treating obesity in children and adolescents. Objective The purpose of this review and meta-analysis was to evaluate the effectiveness of wearable devices as physical activity interventions on obesity-related anthropometric outcomes in children and adolescents. Methods Research articles retrieved from PubMed, EMBASE, Cochrane Library, Scopus, and EBSCO from inception to February 1, 2021, were reviewed. The search was designed to identify studies utilizing wearable devices for preventing and treating obesity in children and adolescents. The included studies were evaluated for risk of bias following the Cochrane recommendation. Meta-analyses were conducted to evaluate the effectiveness of wearable devices as physical activity interventions on body weight, body fat, BMI z-score (BMI-Z), BMI, and waist circumference. Subgroup analyses were performed to determine whether the characteristics of the interventions had an impact on the effect size. Results A total of 12 randomized controlled trials (3227 participants) were selected for meta-analysis. Compared with the control group, wearable device interventions had statistically significant beneficial effects on BMI (mean difference [MD] –0.23; 95% CI –0.43 to –0.03; P=.03; I2=2%), BMI-Z (MD –0.07; 95% CI –0.13 to –0.01; P=.01; I2=81%), body weight (MD –1.08; 95% CI –2.16 to –0.00; P=.05; I2=58%), and body fat (MD –0.72; 95% CI –1.19 to –0.25; P=.003; I2=5%). However, no statistically significant effect was found on waist circumference (MD 0.55; 95% CI –0.21 to 1.32; P=.16; I2=0%). The subgroup analysis showed that for participants with overweight or obesity (MD –0.75; 95% CI –1.18 to –0.31; P<.01; I2=0%), in the short-term (MD –0.62; 95% CI –1.03 to –0.21; P<.01; I2=0%), wearable-based interventions (MD –0.56; 95% CI –0.95 to –0.18; P<.01; I2=0%) generally resulted in greater intervention effect size on BMI. Conclusions Evidence from this meta-analysis shows that wearable devices as physical activity interventions may be useful for preventing and treating obesity in children and adolescents. Future research is needed to identify the most effective physical activity indicators of wearable devices to prevent and treat obesity in children and adolescents.

BACKGROUND The prevalence of obesity in children and adolescents remains a global public health issue. Wearable devices may offer new opportunities for prevention and intervention in obesity. Previous systematic reviews have only examined the effect of the wearable device interventions on preventing and treating obesity in adults. However, no systematic review has provided an evaluation of wearable devices as physical activity interventions for preventing and treating obesity in children and adolescents. OBJECTIVE The purpose of this review and meta-analysis was to evaluate the effectiveness of wearable devices as physical activity interventions on obesity-related anthropometric outcomes in children and adolescents. METHODS Research articles retrieved from PubMed, EMBASE, Cochrane Library, Scopus, and EBSCO from inception to February 1, 2021, were reviewed. The search was designed to identify studies utilizing wearable devices for preventing and treating obesity in children and adolescents. The included studies were evaluated for risk of bias following the Cochrane recommendation. Meta-analyses were conducted to evaluate the effectiveness of wearable devices as physical activity interventions on body weight, body fat, BMI z-score (BMI-Z), BMI, and waist circumference. Subgroup analyses were performed to determine whether the characteristics of the interventions had an impact on the effect size. RESULTS A total of 12 randomized controlled trials (3227 participants) were selected for meta-analysis. Compared with the control group, wearable device interventions had statistically significant beneficial effects on BMI (mean difference [MD] –0.23; 95% CI –0.43 to –0.03; <i>P</i>=.03; <i>I²</i>=2%), BMI-Z (MD –0.07; 95% CI –0.13 to –0.01; <i>P</i>=.01; <i>I²</i>=81%), body weight (MD –1.08; 95% CI –2.16 to –0.00; <i>P</i>=.05; <i>I²</i>=58%), and body fat (MD –0.72; 95% CI –1.19 to –0.25; <i>P</i>=.003; <i>I²</i>=5%). However, no statistically significant effect was found on waist circumference (MD 0.55; 95% CI –0.21 to 1.32; <i>P</i>=.16; <i>I²</i>=0%). The subgroup analysis showed that for participants with overweight or obesity (MD –0.75; 95% CI –1.18 to –0.31; <i>P</i>&lt;.01; <i>I²</i>=0%), in the short-term (MD –0.62; 95% CI –1.03 to –0.21; <i>P</i>&lt;.01; <i>I²</i>=0%), wearable-based interventions (MD –0.56; 95% CI –0.95 to –0.18; <i>P</i>&lt;.01; <i>I²</i>=0%) generally resulted in greater intervention effect size on BMI. CONCLUSIONS Evidence from this meta-analysis shows that wearable devices as physical activity interventions may be useful for preventing and treating obesity in children and adolescents. Future research is needed to identify the most effective physical activity indicators of wearable devices to prevent and treat obesity in children and adolescents.

Introduction: Physical exercise has a positive effect on the health of individuals. Long-term sedentary behavior can induce coronary heart disease, hypertension, diabetes, and other chronic diseases. Lack of physical exercise has become the fourth leading cause of death worldwide. Therefore, youth sports are very important for physical health. Objective: To systematically reveal the influencing factors of adolescents’ physical exercise and improve the effectiveness of interventions on adolescents’ physical exercise behaviors, this article is based on social ecology theory to study the structural model of adolescents’ physical exercise factors. Methods: The thesis considers factors affecting adolescent physical exercise as the research object and uses literature method, questionnaire survey, mathematical statistics, etc., to construct a structural model of factors affecting youth physical exercise, including four primary indicators and 19 secondary indicators. Results: Adolescent physical exercise is affected by the school, family, social and personal factors. Among them, family factors have the greatest impact on young people's physical exercise. Personal factors rank second, school factors, and social factors rank third. Among the family factors, the major influences on youth physical exercise are “parental support,” “parents’ cognition of physical exercise,” and “parental exercise habits.” Conclusions: The influencing factors of adolescent physical exercise involve four aspects: family, society, school, and self. Family factors have the greatest impact on adolescent physical exercise, and personal factors are the second, school factors, and social factors are the third. Level of evidence II; Therapeutic studies - investigation of treatment results.