The Relation between Aerobic Fitness, Muscular Fitness, and Obesity in Children from Three Countries at Different Stages of the Physical Activity Transition

Table 3

Age-adjusted relationship between body composition and aerobic fitness (VO_2max) measures by sex and country.

	Boys				Girls
	Canada	Mexico	Kenya	Differences*	Canada	Mexico	Kenya	Differences*
Body mass index
β (95% CI)	−0.21; (−0.23, −0.19)	−0.43; (−0.57, −0.30)	−0.17; (−0.25, −0.09)	C < M, M > K	−0.22; (−0.27, −0.18)	−0.57; (−0.77, −0.37)	−0.35; (−0.47, −0.22)	C < M, M > K
𝑅^2	0.51	0.31	0.19		0.47	0.32	0.24
Predicted BMI at VO2max 40 mL/kg/min	19.3	22.9	18.0		18.5	22.9	19.3
Predicted BMI at VO2max 50 mL/kg/min	17.2	18.5	16.2		16.5	17.2	15.7
Triceps skinfold
β (95% CI)	−0.32; (−0.39, −0.25)	−0.76; (−0.97, −0.55)	−0.32; (−0.46, −0.18)	C < M, M > K	−0.31; (−0.36, −0.26)	−0.79; (−1.04, −0.55)	−0.75; (−0.97, −0.52)	C < M, C < K
𝑅^2	0.42	0.31	0.19		0.37	0.33	0.32
Waist circumference
β (95% CI)	−0.53; (−0.60, −0.48)	−1.29; (−1.66, −0.92)	−0.32; (−0.52, −0.12)	C < M, M > K	−0.63; (−0.76, −0.50)	−1.46; (−1.98, −0.94)	−0.84; (−1.15, −0.53)	C < M
𝑅^2	0.48	0.34	0.12		0.53	0.32	0.24

∗Country differences identified by nonoverlapping confidence intervals; C: Canada, M: Mexico, and K: Kenya.