The association between family structure and adolescent physical activity levels: A systematic review of literature published since 2010

BackgroundAdolescent physical activity is influenced by biological, psychological, sociocultural, and environmental factors; however, no review has yet explored the effect of family structure (usually defined based on the relationships between people living in a household) on adolescent physical activity levels. MethodsDatabases MEDLINE, EMBASE, Web of Science, PsycINFO, CINAHL, and Sociological Abstracts were searched for peer-reviewed studies with a quantitative component published since 2010, with no restrictions on language, country, and year of data collection. Study screening, data extraction, and quality assessment occurred in duplicate. SWiM guidelines guided the narrative synthesis. PROSPERO protocol CRD42020221090. ResultsThirty studies met inclusion criteria: 17 looked at global physical activity, 13 at leisure physical activity, and sport participation. All studies used cross-sectional designs and 27 assessed outcomes through a survey. Sixteen (10 of good quality) reported a significant association between family structure and adolescent physical activity. Of these, three did not specify the direction of this association while nine found adolescents in traditional (two-parent) families were more physically active compared with other family structures. This association was stronger in studies of leisure- time physical activity. Two studies reported that adolescents with single mothers achieve more physical activity than adolescents living with neither parent. Two studies, focused on school physical exercise classes and active transport, found adolescents in single-parent households engaged in more physical activity than those living with two parents. ConclusionHigh-quality accelerometery, time diary, and longitudinal studies are needed to investigate the effect of family structure on adolescent physical activity and health sequelae. An improved understanding of social determinants of adolescent physical activity could inform health promotion strategies.