Tracking of Physical Activity across the Lifespan.

This report considers evidence for tracking of indicators of physical activity during childhood and adolescence, the transition from adolescence into adulthood, and adulthood. Tracking refers to the tendency of individuals to maintain their rank or position within a group over time. Longitudinal data for at least two points in time are necessary. Presently available data are from longitudinal studies which include an indicator of physical activity. The issue of tracking or stability is inherent in longitudinal studies. Three studies of combined samples of boys and girls provide the only information for childhood. Data are more available for boys and girls followed from late childhood into adolescence. Data tracking indicators of physical activity within adulthood are most available for the short term and are derived from follow-up studies of adolescents. Several studies have asked adults to recall their activity histories during adolescence and young adulthood, then related these estimates to present physical activity levels. The research suggests significant, moderate to low interage correlations for a variety of indicators of physical activity from childhood through adulthood. The report concludes that physical activity is a biocultural behavior, with individuals expending energy or applying ground reactions forces in movement behaviors that occur within a cultural context. (Contains 40 references.) (SM)