Comparison of 3 measures of physical activity and associations with blood pressure, HDL, and body composition in a sample of adolescents.
BACKGROUND
The association of physical activity (PA), measured 3 ways, and biomarkers were compared in a sample of adolescents.


METHODS
PA data were collected on 2 cohorts of adolescents (N = 700) in the Twin Cities, Minnesota, 2007-2008. PA was measured using 2 survey questions [Modified Activity Questionnaire (MAQ)], the 3-Day Physical Activity Recall (3DPAR), and accelerometers. Biomarkers included systolic (SBP) and diastolic blood pressure (DBP), lipids, percent body fat (%BF), and body mass index (BMI) percentile. Bivariate relationships among PA measures and biomarkers were examined followed by generalized estimating equations for multivariate analysis.


RESULTS
The 3 measures were significantly correlated with each other (r = .22-.36, P < .001). Controlling for study, puberty, age, and gender, all 3 PA measures were associated with %BF (MAQ = -1.93, P < .001; 3DPAR = -1.64, P < .001; accelerometer = -1.06, P = .001). The MAQ and accelerometers were negatively associated with BMI percentile. None of the 3 PA measures were significantly associated with SBP or lipids. The percentage of adolescents meeting the national PA recommendations varied by instrument.


CONCLUSIONS
All 3 instruments demonstrated consistent findings when estimating associations with %BF, but were different for prevalence estimates. Researchers must carefully consider the intended use of PA data when choosing a measurement instrument.
Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA.
Mary O
MO
Hearst
John R
JR
Sirard
Leslie
L
Lytle
Donald R
DR
Dengel
David
D
Berrigan
D000054:Acceleration; D056044:Actigraphy / Q000379:methods; D000273:Adipose Tissue; D000293:Adolescent; D015415:Biomarkers; D001794:Blood Pressure / Q000502:physiology*; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D002648:Child; D008076:Cholesterol, HDL / Q000097:blood*; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D011939:Mental Recall; D009043:Motor Activity / Q000502:physiology*; D015999:Multivariate Analysis; D013223:Statistics as Topic; D011795:Surveys and Questionnaires
D015415:Biomarkers; D008076:Cholesterol, HDL