Table 7.

Correlations between sleep and physical activity in children 13–18 years

Children (n = 38)	Time in bed (h/day)	Total sleep time (h/day)	Sleep efficiency (%)	Sleep fragmentation Index (%)
Median duration of prolonged sedentary bouts (min)	r = − 0.06 p = 0.74	r = − 0.07 p = 0.69	r = − 0.05 p = 0.79	r = 0.12 p = 0.48
Total prolonged sedentary bout time (min/day)	r = − 0.46 p = 0.005	r = − 0.48 p = 0.003	r = − 0.12 p = 0.48	r = 0.30 p = 0.08
Total activity Z-score (standard deviations)	r = 0.10 p = 0.55	r = 0.13 p = 0.47	r = − 0.10 p = 0.55	r = 0.21 p = 0.23

Spearman correlation coefficients. Significant correlations in bold