Sedentary behaviour linked to anxiety symptoms in teens

Adolescents who spend prolonged hours being sedentary are likely to develop anxiety symptoms, regardless of physical activity levels, as reported in a study.

The analysis included a UK cohort of 4,257 adolescents aged 12 years at baseline (56 percent girls) whose sedentary behaviour and physical activity was measured using accelerometers worn for 7 days at ages 12, 14, and 16 years. They underwent the Clinical Interview Schedule-Revised (CIS-R) for assessment of anxiety symptoms at age 18 years.

Overall physical activity levels declined over 4 years, from 602.33 counts per minutes (CPM) at age 12 to 474.83 CPM at age 16. Within the same period, sedentary behaviour increased from 7.18 to 8.72 hours per day and light physical activity decreased from 5.43 to 4.08 hours per day, whereas moderate-to-vigorous physical activity (MVPE) remained relatively stable.

Based on adjusted negative binomial regression and iso-temporal substitution methods, sedentary behaviour at ages 12, 14, and 16 showed a positive association with anxiety symptoms at age 18, independent of total physical activity levels.

For an additional 60-minutes of sedentary behaviour at ages 12, 14, and 16, anxiety scores at age 18 increased by 18.22 percent, 10.19 percent, and 15.75 percent, respectively. Conversely, adding an hour of light activity at ages 12, 14, and 16 reduced anxiety scores at age 18 by 16.82 percent, 11.57 percent, and 14.81 percent, respectively.

When replacing an hour of daily sedentary behaviour with light activity at ages 12, 14, and 16, anxiety symptoms by age 18 decreased by 15.9 percent, 12.1 percent, and 14.7 percent, respectively. On the other hand, replacing an hour of sedentary behaviour with MVPA had a null effect. These results were robust to sensitivity analyses.