on November 17, 2008
Published online before print November 17, 2008, doi: 10.1161/CIRCULATIONAHA.108.791988
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Submitted on May 16, 2008
From the Research Centre of Applied and Preventive Cardiovascular Medicine (K.P., O.S., M.H., L.S., O.T.R.); Paavo Nurmi Centre, Sports and Exercise Medicine Unit, Department of Physiology (K.P., O.J.H., M.H.); and Departments of Pediatrics (O.J.H., O.S.), Medicine (J.S.A.V., T.R.), and Clinical Physiology (O.T.R.), University of Turku; Turku Institute for Child and Youth Research (H.L., O.S.); and Research Department of the Social Insurance Institution (P.H.), Turku, Finland. * To whom correspondence should be addressed. E-mail: katja.pahkala{at}utu.fi.
Background—Exercise training improves endothelial function in high-risk adolescents, but the influence of habitual leisure-time physical activity on endothelial function in healthy adolescents is unknown. Methods and Results—Brachial artery flow-mediated endothelial function and physical activity habits were assessed in 483 adolescents (13 years of age) participating in an atherosclerosis prevention study (Special Turku Coronary Risk Factor Intervention Project for Children [STRIP]). Endothelial function was examined with ultrasound; physical activity was assessed with self-administered questionnaires. A leisure-time physical activity index was calculated by multiplying mean weekly leisure-time exercise intensity, duration, and frequency [boys, 31.2±23.0 MET h/wk (mean±SD); girls, 24.0±20.9 MET h/wk; P for gender difference=0.0003]. Maximum flow-mediated dilatation (FMD) and total FMD response (the area under the dilatation curve 40 to 180 seconds after hyperemia) were calculated. In boys, maximum FMD and area under the dilatation curve 40 to 180 seconds after hyperemia were directly associated with leisure-time physical activity index in regression analyses adjusted for brachial artery diameter (maximum FMD, P=0.020; area under the dilatation curve 40 to 180 seconds after hyperemia, P=0.0055). These associations remained significant after further adjustments for body mass index, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, high-sensitivity C-reactive protein, and systolic blood pressure. A difference of Conclusions—Leisure-time physical activity is directly associated with brachial artery FMD responses in 13-year-old boys, providing evidence that physical activity beneficially influences endothelial function in healthy male adolescents. Lack of association in girls may reflect their overall lower physical activity level.
Accepted on October 3, 2008
Vascular Endothelial Function and Leisure-Time Physical Activity in Adolescents
Katja Pahkala MSc*,
50 MET h/wk corresponding to 10 hours of moderate intensity activity weekly between sedentary and active boys was associated with an 1% unit difference in maximum FMD.
Key words: children • endothelium • exercise • ultrasound
Related Article:
Circulation 2008 118: 2319-2320.