Background: Previous studies have reported on the associations between obesity and sedentary behavior (SB) or physical activity (PA) for children. The present study examined longitudinal and bidirectional associations between adiposity and SB and PA in children. Methods: Participants were 356 children in England. PA was measured at age 7 and 9 years using accelerometry. Outcome and exposures were time in SB and PAs and concurrent body mass index (BMI) Z-score and fat index (FI). Results: Adiposity at baseline was positively associated with change in SB (β=0.975, for FI) and negatively associated with changes in moderate-to-vigorous PA (MVPA) (β=-0.285 for BMI Z-score, β=-0.607 for FI), vigorous PA (VPA) (β= -0.095 for FI) and total PA (β=-48.675 for FI), but not vice versa. The changes in SB, MVPA and total PA for children with overweight/obesity were significantly more adverse than those of healthy weight children. Conclusions: A high BMI Z-score or high body fatness at baseline was associated with lower MVPA and VPA after 2 years, but not vice versa, which suggests that in this cohort adiposity influenced PA and SB, but the associations between adiposity and SB or PA were not bidirectional.
|Number of pages||19|
|Journal||Journal of Physical Activity and Health|
|Publication status||Accepted/In press - 22 Jun 2018|
- sedentary behavior
- physical activity
- child health
Tanaka, C., Janssen, X., Basterfield, L., Parkinson, K., Pearce, M., Reilly, J., ... Reilly, J. (Accepted/In press). Bidirectional associations between adiposity, sedentary behavior and physical activity: a longitudinal study in children. Journal of Physical Activity and Health.