Abstract
PURPOSE: The relationship between sedentary time, physical activity, and cardiometabolic risk factors during the transition from adolescence to adulthood remains uncertain. We examined the prospective associations of sedentary time and physical activity at age 15 yr with cardiometabolic risk markers at age 24 yr. METHODS: We used data from the Physical Activity among Norwegian Children Studies. Sedentary time, moderate-to-vigorous physical activity (MVPA), and vigorous physical activity (VPA) were measured by accelerometry. Outcomes included body mass index (BMI), waist circumference, visceral fat, maximal oxygen uptake (V̇O 2max ), systolic blood pressure, LDL-cholesterol, insulin, high-sensitivity C-reactive protein, and a clustered risk Z -score. The prospective associations were modeled through regression. RESULTS: A total of 731 boys and girls participated at ages 9 yr (2005-2006) and 15 yr (2011-2012), and 258 of these participated again at age 24 yr (2019-2021). Multiple imputation was performed for all eligible individuals ( n = 708). Each standard deviation increase (minutes per day) in sedentary time at age 15 yr was associated with lower V̇O 2max at age 24 yr ( β = -1.6 mL·kg -1 ·min -1 ; 95% confidence interval (CI), -2.8 to -0.5). Each standard deviation increase (minutes per day) in MVPA ( β = 1.6 mL·kg -1 ·min -1 ; 95% CI, 0.8 to 2.4) and VPA ( β = 1.6 mL·kg -1 ·min -1 ; 95% CI, 0.8 to 2.4) at age 15 yr were associated with higher V̇O 2max at age 24 yr. VPA in adolescence was further inversely associated with visceral fat mass ( β = -41 g; 95% CI, -78 to -3), insulin level ( β = -4.3 pmol·L -1 ; 95% CI, -8.2 to -0.4), and the clustered risk Z -score ( β = -0.09; 95% CI, -0.18 to -0.01) in young adulthood. Childhood BMI modified the association of both MVPA and VPA with clustered risk, with the greatest magnitude of association observed in the highest BMI tertile. CONCLUSIONS: Physical activity, especially of vigorous intensity, during adolescence appears to beneficially affect cardiometabolic health in young adulthood. These health benefits may be most pronounced among overweight/obese youth.