Two Family Gradients in Children’s Physical Activity and Fitness: Socioeconomic Position, Family Structure, and Where They Diverge

Background/Objectives: Family circumstances are related to children’s physical activity and fitness, yet the two are rarely examined together in the same children. We examined how socioeconomic position and family structure (only-child status) relate to domain-specific reported activity and measured fitness. Socioeconomic position was the mean of maternal and paternal educational attainment, with higher values indicating higher attainment.