Sedentary Time, Physical Activity, and Executive Function in a Longitudinal Study of Youth

This study examined associations between sedentary time, physical activity (PA), and executive function among youth participating in the Study of Early Child Care and Youth Development.

Sedentary time and PA (light, moderate, vigorous, and moderate-to-vigorous (MVPA)) were objectively assessed at 9 and 15 years, while executive function (inhibition, working memory, and fluid intelligence) were assessed at 15 years. Regression models were used to examine associations.

Sedentary time at 9 years predicted fluid intelligence at 15 years (B = 0.031), whereas increased sedentary time from 9 to 15 years predicted higher inhibition (B = 0.003), working memory (B = 0.074), and fluid intelligence (B = 0.029). Relatively lower levels of working memory at 15 years were predicted from increased levels of light PA, moderate PA, and MVPA from 9 to 15 years (B = -0.075, -0.293, and -0.173, respectively). At 15 years, inhibition, working memory, and fluid intelligence were significantly associated with sedentary time (B = 0.003, 0.055, and 0.045, respectively).

Childhood sedentary time and PA may affect executive function at 15 years; however, prospective studies are needed to examine the concurrent change in both sedentary time and PA with executive function.