Aim Aerobic fitness is associated with cardiometabolic risk factors in children. Associations with traditional measures of lipid metabolism are uncertain. We investigated whether higher levels of fitness benefit lipid metabolism by exploring cross-sectional and prospective associations between aerobic fitness and a comprehensive lipoprotein profile.

Methods We used targeted proton nuclear magnetic resonance (¹H NMR) spectroscopy to profile 29 measures of lipoprotein metabolism for 811 fifth-grade Norwegian schoolchildren (50.1% girls; mean age 10.2 years). Serum samples were taken on two occasions across the academic year. Aerobic fitness was measured at baseline using the Andersen aerobic fitness test. We used multiple linear regression adjusted for potential confounders to examine both cross-sectional and prospective — adjusted for baseline lipoprotein measure — associations between aerobic fitness and lipoprotein profiles.

Results Higher levels of aerobic fitness were associated with all measures of lipoprotein metabolism in the cross-sectional analysis. There were inverse associations with the apolipoprotein B-containing (apo B) lipoprotein subclasses, including cholesterol and triglyceride concentration. The associations between aerobic fitness and the concentration of high-density lipoprotein (HDL) particles were divergent between larger and smaller subclasses. In the prospective analysis, the inverse associations between aerobic fitness and the measures of larger apo B-containing lipoprotein subclasses persisted as did all but one of the associations with triglyceride concentrations. Additional adjustment for adiposity attenuated most associations in both cross-sectional and prospective models, but an independent effect of fitness remained for certain measures.

Conclusions Higher levels of aerobic fitness are associated with a favourable lipoprotein profile, partly independent of adiposity. Associations tended to be stronger and more consistent over time for the larger apo B-containing lipoprotein measures and those of triglyceride concentration. Our results suggest that improving children’s fitness levels should have beneficial effects on lipoprotein metabolism, though a concomitant reduction in adiposity would likely be more effective.

References

1. Anderssen SA, Cooper AR, Riddoch C, Sardinha LB, Harro M, Brage S, et al. Low cardiorespiratory fitness is a strong predictor for clustering of cardiovascular disease risk factors in children independent of country, age and sex. Eur J Cardiovasc Prev Rehabil 2007.

2. Mintjens S, Menting MD, Daams JG, van Poppel MNM, Roseboom TJ, Gemke RJBJ. Cardiorespiratory fitness in childhood and adolescence affects future cardiovascular risk factors: a systematic review of longitudinal studies. Sports Med 2018 Nov 1;48(11):2577–605.