Light-intensity physical activity and cardiometabolic biomarkers in US adolescents

PLoS One. 2013 Aug 9;8(8):e71417. doi: 10.1371/journal.pone.0071417. eCollection 2013.

Abstract

Background: The minimal physical activity intensity that would confer health benefits among adolescents is unknown. The purpose of this study was to examine the associations of accelerometer-derived light-intensity (split into low and high) physical activity, and moderate- to vigorous-intensity physical activity with cardiometabolic biomarkers in a large population-based sample.

Methods: The study is based on 1,731 adolescents, aged 12-19 years from the 2003/04 and 2005/06 National Health and Nutrition Examination Survey. Low light-intensity activity (100-799 counts/min), high light-intensity activity (800 counts/min to <4 METs) and moderate- to vigorous-intensity activity (≥ 4 METs, Freedson age-specific equation) were accelerometer-derived. Cardiometabolic biomarkers, including waist circumference, systolic blood pressure, diastolic blood pressure, HDL-cholesterol, and C-reactive protein were measured. Triglycerides, LDL- cholesterol, insulin, glucose, and homeostatic model assessments of β-cell function (HOMA-%B) and insulin sensitivity (HOMA-%S) were also measured in a fasting sub-sample (n=807).

Results: Adjusted for confounders, each additional hour/day of low light-intensity activity was associated with 0.59 (95% CI: 1.18-0.01) mmHG lower diastolic blood pressure. Each additional hour/day of high light-intensity activity was associated with 1.67 (2.94-0.39) mmHG lower diastolic blood pressure and 0.04 (0.001-0.07) mmol/L higher HDL-cholesterol. Each additional hour/day of moderate- to vigorous-intensity activity was associated with 3.54 (5.73-1.35) mmHG lower systolic blood pressure, 5.49 (1.11-9.77)% lower waist circumference, 25.87 (6.08-49.34)% lower insulin, and 16.18 (4.92-28.53)% higher HOMA-%S.

Conclusions: Time spent in low light-intensity physical activity and high light-intensity physical activity had some favorable associations with biomarkers. Consistent with current physical activity recommendations for adolescents, moderate- to vigorous-intensity activity had favorable associations with many cardiometabolic biomarkers. While increasing MVPA should still be a public health priority, further studies are needed to identify dose-response relationships for light-intensity activity thresholds to inform future recommendations and interventions for adolescents.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Blood Glucose / metabolism
  • Blood Pressure / physiology
  • C-Reactive Protein / metabolism
  • Child
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Exercise / physiology*
  • Female
  • Humans
  • Insulin / blood
  • Insulin-Secreting Cells / physiology*
  • Male
  • Nutrition Surveys / statistics & numerical data*
  • Triglycerides / blood
  • Waist Circumference / physiology

Substances

  • Blood Glucose
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Insulin
  • Triglycerides
  • C-Reactive Protein

Grant support

VC was supported by Endeavour Research Fellowship; NDR is supported by an Australian Research Council (ARC) Discovery Early Career Researcher Award; GNH is supported by a National Health and Medical Research Council (NHMRC) [number 569861] Training Fellowship; NO is supported by a NHMRC Program Grant [number 569940], a Senior Principal Research Fellowship [number 1003960], and the Victorian Government’s Operational Infrastructure Support Program; DD is supported by an ARC Future Fellowship; and JS is supported by a NHMRC Principal Research Fellowship [number 1026216]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.