A Systematic Review of Information and Communication Technology–Based Interventions for Promoting Physical Activity Behavior Change in Children and Adolescents

This study examined the effects of a 6‐week intermittent exercise training, at different intensities, on body composition, functional walking and aerobic endurance in overweight children. Forty‐eight overweight children (age: 10.4 ± 0.9 years) were randomly assigned to either intervention or control group. Lower and higher intensity intermittent exercise groups (LIIE and HIIE) performed intermittent running three times a week. LIIE performed more intervals at a lower intensity [16 intervals at 100% of individual maximal aerobic speed (MAS), 8 minutes in total], and HIIE performed fewer intervals at a higher intensity (12 intervals at 120% of MAS, 6 minutes in total). Each interval consisted of a 15‐second run at the required speed, followed by a 15‐second passive recovery. After 6 weeks, HIIE had a significantly (p < 0.05) higher percentage reduction in sum of skinfolds (i.e. calf and triceps), and significantly (p < 0.05) fewer steps during the functional obstacle performance, as compared with LIIE and control group. Significant improvement (p < 0.05) was found in intermittent aerobic endurance for HIIE as compared to the control group. Higher intensity intermittent training is an effective and time‐efficient intervention for improving body composition, functional walking and aerobic endurance in overweight children.

AIMS—(1) To validate a leg to leg bioimpedance analysis (BIA) device in the measurement of body composition in children by assessment of its agreement with dual energy x ray absorptiometry (DXA) and its repeatability. (2) To establish a reference range of percentage body fat in Hong Kong Chinese children. METHODS—Sequential BIA and DXA methods were used to determine body composition in 49 children aged 7-18 years; agreement between the two methods was calculated. Repeatability for the BIA method was established from duplicate measurements. Body composition was then determined by BIA in 1139 girls and 1243 boys aged 7-16 years, who were randomly sampled in eight local primary and secondary schools to establish reference ranges. RESULTS—The 95% limits of agreement between BIA and DXA methods were considered acceptable (−3.3 kg to −0.5 kg fat mass and −3.9 to 0.6% body fat). The percentage body fat increased with increasing age. Compared to the 1993 Hong Kong growth survey, these children had higher body mass index. Mean (SD) percentage body fat at 7years of age was 17.2% (4.4%) and 14.0% (3.4%) respectively for boys and girls, which increased to 19.3% (4.8%) and 27.8% (6.3%) at age 16. CONCLUSION—Leg to leg BIA is a valid alternative method to DXA for the measurement of body fat. Provisional reference ranges for percentage body fat for Hong Kong Chinese children aged 7-16 years are provided.

Sport has been an integral part of the Chinese government’s policy agenda since the People’s Republic of China was founded in 1949. The policy prominence of sport has been further elevated in the last two to three decades, as indicated by the steady increase in elite sport success, the hosting of sports events such as the Olympic Games, China’s increased global engagement with sport organisations and the developments in sport professionalisation and commercialisation. This article reviews China’s sport policy at different periods since its inception, analyses the rationale for, and form and extent of, government intervention, presents the sport structure in China and identifies the dominant characteristics of its sport policy. In addition, various sport policy areas, ranging from elite sport and mass sport to sports mega-events, and sports professionalisation are discussed, and their relative policy significances are compared. The degree of balance between these areas and policy priorities are thus defined. Finally, emerging trends and issues are introduced.

Physical activity (PA) correlates have not been extensively studied in Hong Kong children. The aim of this study is to assess the validity and reliability of translated scales to measure PA related self-efficacy, enjoyment and social support in Hong Kong Chinese children. Sample 1 (n = 273, aged 8-12 years) was recruited (May-June, 2013) from two primary schools. Confirmatory factor analyses (CFA) were conducted to assess factorial validity. Criterion validity was assessed by correlating measured constructs with self-reported PA. Cronbach's alpha was computed to assess scale internal consistency. The intraclass correlation coefficient (ICC) was performed to assess scale test-retest reliability. Criterion validity was further examined in Sample 2 (n = 84, aged 8-12 years) from a third school by correlating measured constructs with objectively measured PA collected in September 2013 and February 2014. The CFA results supported the one-factor structure of the scales. All PA correlates were significantly (p < 0.01) associated with self-reported PA in Sample 1. Self-efficacy and enjoyment were significantly (p < 0.05) correlated with objectively measured PA in Sample 2. All the scales demonstrated acceptable internal consistency. All ICC values of the scales suggested acceptable test-retest reliability. The results provide psychometric support for using the scales to measure PA correlates among Hong Kong Chinese children.

The chronic health effects from exposure to ambient air pollution are still unclear. This study primarily aims to examine the relationship between long-term exposure to ambient air pollution and respiratory morbidities in Chinese children.