Table 3: Hierarchical regression models of correlates of cardiorespiratory fitness according to sex, nutritional status and maturity status (n = 1,209).

	Sex		Nutritional status		Somatic maturity status
	Boys	Girls	Normal weight	Overweight/obese	Late	On time	Early
First level
Adjusted R²	0.012	0.015	0.216	0.095	0.263	-	0.112
Socioeconomic status	-	-0.34 (-0.63 to -0.04)	-	-	-	-	-
Maternal educational status	-0.46 (-0.87 to -0.04)	-	-	-	-	-	-
Paternal body mass index	-	-	-	-0.14 (-0.268 to -0.029)	-	-	-
Maternal physical activity status	-	2.38 (0.41 to 4.34)	-	-	4.57 (0.686 to 8.462)	-	-
Number of siblings	-	-	0.195 (0.058 to 0.331)	-	-	-	0.297 (0.040 to 0.555)
Second level
Adjusted R²	0.081	0.104	0.280	0.149	0.307	0.203	0.165
Tobacco smoking	-	-2.65 (-4.12 to -1.18)	-	-2.92 (-5.494 to -0.354)	-	-	-
Alcohol consumption	-	-0.92 (-1.83 to -0.01)	-1.372 (-2.115 to -0.629)	-	-	-1.249 (-2.049 to -0.449)	-
Early physical activity	-	-	-	1.51 (0.278 to 2.749)	-	0.671 (0.011 to 1.330)	-
Habitual physical activity	0.93 (0.59 to 1.27)	0.44 (0.18 to 0.71)	0.705 (0.492 to 0.918)	-	1.10 (1.499 to 1.703)	0.515 (0.278 to 0.752)	0.619 (0.207 to 1.032)
Screen time	-	-0.14 (-0.21 to -0.07)	-0.099 (-0.155 to -0.044)	-	-	-	-
Third level
Adjusted R²	0.246	0.333	0.401	0.253	0.458	0.365	0.425
Chronological age	-	-1.54 (-1.80 to -1.28)	-0.854 (-1.134 to -0.574)	-0.548 (-0.987 to -0.108)	-1.53 (-2.085 to -0.994)	-0.545 (-0.771 to -0.319)	-
Age at peak height velocity	-	0.70 (0.19 to 1.21)	-0.675 (-1.230 to -0.121)	-	-	-	-
Waist circumference	-0.22 (-0.27 to -0.17)	-	-0.080 (-0.150 to -0.010)	-0.120 (-0.191 to -0.050)	-	-0.199 (-0.239 to -0.159)	-0.192 (-0.238 to -0.146)

Non-significant models are not presented; P < 0.05; Adjusted according to sex.