Patterns of objectively measured sedentary time in 10- to 12-year-olds

In a study just published in BMC pediatrics we examined the frequency of sedentary 'bouts' of different durations and the total time spent in sedentary on a weekday, a weekend day, during school hours, during after-school hours and during evenings among 10- to 12-year-old Belgian children. The study was part of the “EuropeaN Energy balance Research to prevent excessive weight Gain among Youth” (ENERGY)-project. We looked at total sitting time as well as different bouts of sitting, because uninterrupted sitting may be more harmful.
Accelerometer data were used to assess sedentary time and sedentary bouts. Differences in total sedentary time, sedentary bouts of 2–5, 5–10, 10–20, 20–30 and ≥30 min and total time accumulated in those bouts were examined on a weekday, a weekend day, during school hours, during after-school hours and in the evening period.
More than 60% of the participants’ waking time was spent sedentary. Children typically engaged in short sedentary bouts of 2–5 and 5–10 min, which was almost 50% of their total daily sedentary time. Although the differences were very small, children engaged in significantly fewer sedentary bouts of nearly all durations during after-school hours compared to during school hours and in the evening period. Children also engaged in significantly fewer sedentary bouts of 5–10, 10–20, and 20–30 min per hour on a weekend day than on a weekday.
Although primary school children spend more than 60% of their waking time sitting, they generally do interrupt their sitting time frequently. Children’s sedentary bouts were slightly longer on weekdays, particularly during school hours and in the evening period.