Background:It is not clear the extent to which change in adiposity and cardiovascular fitness (CRF) during early childhood are associated with change in cardiovascular risk factors or if associations are independent or interactive.Methods:383 Danish children were examined at ages 6 and 9. CRF, sum of skinfolds (SSF), and blood pressure were assessed. Fasting blood samples were used to calculate total cholesterol (TC), high and low density lipoprotein cholesterol (HDL-C & LDL-C), triglycerides, insulin, glucose, and HOMA-IR. Regression models examined whether CRF change or SSF change were independently or interactively associated with risk variables.Results:Change in SSF was independently associated with change in TC (z =4.83, P < .0o1), LDL-C (z =4.38, P < .001), systolic (z = 3.45, P < .001), and diastolic (z = 2.45, P = .014) blood pressure. CRF change was independently associated with change in TC (z =-3.86, P < .001), HDL-C (z =3.85, P < .001), and systolic blood pressure (z = 2.06, P = .040).Conclusions:Change in fitness and adiposity were independently associated with the development of cardiovascular risk factors among young children suggesting a need to increase CRF and prevent weight gain early during development to improve cardiovascular health.