Gender, Ethnicity, and Socioeconomic Inequalities in Physical Activity Throughout the Life Course: A Systematic Review of Cohort Studies

Background: This study aimed to assess longitudinal changes in physical activity inequalities according to gender, socioeconomic status, and ethnicity throughout the life course. Methods: We searched PubMed, Embase, Web of Science, and Scopus databases for cohort studies addressing trajectories or monitoring physical activity at a minimum of 2 time points, presenting stratified estimates for at least 1 dimension of inequality (gender, socioeconomic status, or ethnicity). Main methodological characteristics and physical activity point estimates were extracted, enabling interpretation of the stability or increasing/ decreasing inequalities over time. Results: Out of the 22 included studies in the review, none were designed or presented with specific aims addressing changes in physical activity according to the dimension of inequalities throughout the life course. Therefore, the main results and interpretation were performed according to available information. Males consistently showed a higher prevalence of physical activity than females. We observed both an increase and stability in gender inequality during childhood, followed by an increase in the transition from childhood to adolescence. During adolescence, both increase and stability in gender inequality were identified, with mixed results observed during adulthood, and in later life stages, in a limited number of studies. There is no or very limited evidence regarding ethnicity and socioeconomic status inequalities throughout the life course. Conclusion: Although none of the studies directly measured inequalities, an early emergence of gender inequalities was observed. Future research should include these dimensions as well as other social identities to enhance the understanding of inequalities throughout the life course.