The Dose-Response Relationship Between Physical Activity and Cardiometabolic Health in Young Adults.

PURPOSE:Guidelines recommend 150 minutes of weekly moderate-to-vigorous physical activity (MVPA) for all adults, although physical activity level correlation with cardiometabolic health is not well characterized for young adults. We determined the dose-response relationship of MVPA on measures of cardiometabolic health in young adults. METHODS:We examined young adults (aged 20-29 years; N = 5,395, 47.9% female) in the 2003-2016 National Health and Nutrition Examination Survey. Exposures were objective (accelerometer based) and self-reported weekly mean minutes of MVPA. Cardiometabolic outcome measures were body mass index (BMI), high-density lipoprotein (HDL), total cholesterol, systolic blood pressure, and diastolic blood pressure. The dose-response relationships were assessed with unadjusted spline analyses. Sex-stratified outcomes were modeled using multivariable linear regression with mean estimated change presented for 150-minute dose increases of MVPA. RESULTS:Among females, associations between objective activity and cardiometabolic measures were all linear. Compared with no activity, 150 minutes of objective activity was associated with a lower BMI (-1.37 kg/m2) and total cholesterol (-4.89 mg/dL), whereas 150 minutes of self-reported activity was associated with a higher HDL (1 mg/dL) and lower diastolic blood pressure (-.42 mm Hg). Among males, an inflection point was identified in the dose-response curves for objective activity with BMI around 100 minutes. Compared with no activity, 150 self-reported minutes was associated with lower BMI (-.26 kg/m2), higher HDL (.52 mg/dL), and lower total cholesterol (-1.35 mg/dL). CONCLUSIONS:The dose-response relationships between physical activity and cardiometabolic markers in young adults were predominantly linear, supporting public health calls for any increase in physical activity in this population.