Global prevalence of physical activity for children and adolescents; inconsistencies, research gaps, and recommendations: a narrative review.

BACKGROUND: One of the strategic actions identified in the Global Action Plan on Physical Activity (PA) 2018-2030 is the enhancement of data systems and capabilities at national levels to support regular population surveillance of PA. Although national and international standardized surveillance of PA among children and adolescents has increased in recent years, challenges for the global surveillance of PA persist. The aims of this paper were to: (i) review, compare, and discuss the methodological inconsistencies in children and adolescents' physical activity prevalence estimates from intercontinental physical activity surveillance initiatives; (ii) identify methodological limitations, surveillance and research gaps. METHODS: Intercontinental physical activity surveillance initiatives for children and adolescents were identified by experts and through non-systematic literature searches. Prevalence of meeting PA guidelines by country, gender, and age were extracted when available. A tool was created to assess the quality of the included initiatives. Methods and PA prevalence were compared across data/studies and against the methodological/validity/translation differences. RESULTS: Eight intercontinental initiatives were identified as meeting the selection criteria. Methods and PA definition inconsistencies across and within included initiatives were observed, resulting in different estimated national prevalence of PA, and initiatives contradicting each other's cross-country comparisons. Three findings were consistent across all eight initiatives: insufficient level of PA of children and adolescents across the world; lower levels of PA among girls; and attenuation of PA levels with age. Resource-limited countries, younger children, children and adolescents not attending school, with disability or chronic conditions, and from rural areas were generally under/not represented. CONCLUSIONS: There are substantial inconsistencies across/within included initiatives, resulting in varying estimates of the PA situation of children and adolescents at the global, regional and national levels. The development of a new PA measurement instrument that would be globally accepted and harmonized is a global health priority to help improve the accuracy and reliability of global surveillance.

Examining lifestyle behaviours and weight status of primary schoolchildren: using Mozambique to explore the data gaps in low- and middle-income countries.

The emergency of malnutrition and physical inactivity among children as serious public health challenges in low- and middle-income countries (LMICs) is concerning and requires urgent attention. The main objective of this dissertation was to examine relationships between lifestyle behaviours and weight status among schoolchildren in Mozambique and use findings to highlight important data gaps that exist in LMICs. Narrative literature searches conducted identified data gaps and research needs. A published protocol was used for this dissertation (n = 683) to facilitate data comparability. Anthropometric and accelerometry data were objectively measured while data about lifestyle behaviours and environmental factors were collected using context-adapted questionnaires. As part of this dissertation, 6 manuscripts were developed and submitted for publication in peer-reviewed scientific journals. Results showed a dearth of information and that overweight/obesity is an emerging public health concern, especially among urban children. Moderate- to vigorous-intensity physical activity (MVPA), active transport, and maternal body mass index (BMI) were important modifiable correlates of weight status for Mozambican children. Distinct differences in prevalences of lifestyle behaviours were observed between urban and rural children in Mozambique. Compared with children from 12 other countries, children from Mozambique had lower BMI, higher daily MVPA, lower daily sedentary time, and comparable sleep duration. Linear distributions of study site-specific BMI, minutes of daily MVPA, and daily sedentary time by country human development index were observed. Findings revealed important differences between urban and rural children, supporting the need to include both in study samples and especially in LMICs where most people live in rural areas.