Activity Behaviors in Schoolchildren and Subsequent 5-yr Change in Blood Pressure

Gopinath, Bamini1; Hardy, Louise L.2; Kifley, Annette1; Baur, Louise A.3,4; Mitchell, Paul1

Medicine & Science in Sports & Exercise: April 2014 - Volume 46 - Issue 4 - p 724–729
doi: 10.1249/MSS.0000000000000166
Epidemiology

Purpose: This study aimed to establish whether time spent in sport-related physical activities and sedentary behaviors (e.g., TV viewing, videogame usage, and homework) was prospectively associated with change in blood pressure (BP) for 5 yr.

Methods: Eight hundred and twenty-one students age 6 yr at baseline (397 girls and 424 boys) were examined from 2003–2004 to 2009–2011. Children completed detailed activity questionnaires. BP was measured using a standardized protocol.

Results: After adjusting for age, ethnicity, parental education, parental history of hypertension, baseline height, BP, body mass index (BMI), baseline time spent in corresponding activity behavior, and change in BMI, each hour per day spent in total screen time was associated with a 0.69 and 0.59 mm Hg increase in diastolic BP (P = 0.01) and mean arterial BP (P = 0.01), respectively. In boys, each hour per day spent in TV viewing was associated with a concurrent 1.42-mm Hg increase in diastolic BP (P = 0.04) during the 5 yr. Children engaging in low sport-related physical activities at baseline but who engaged in high levels of physical activity (≥60 min·d−1) at follow-up (n = 154) compared with those engaging in low sport-related physical activities at both examinations (n = 305) demonstrated significantly lower mean arterial BP, 7.26 versus 9.61 mm Hg (P = 0.04).

Conclusions: Time spent in physical activity and screen time could influence BP measures during childhood.

1Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, NSW, AUSTRALIA; 2Physical Activity, Nutrition and Obesity Research Group, University of Sydney, Sydney, NSW, AUSTRALIA; 3University of Sydney Clinical School, The Children’s Hospital at Westmead, Sydney, NSW, AUSTRALIA; and 4School of Public Health, University of Sydney, Sydney, NSW, AUSTRALIA

Address for correspondence: Bamini Gopinath, Ph.D., Centre for Vision Research, Westmead Millennium Institute, University of Sydney, Westmead Hospital, Hawkesbury Rd., Westmead, NSW, 2145, Australia; E-mail: bamini.gopinath@sydney.edu.au.

Submitted for publication May 2013.

Accepted for publication September 2013.

© 2014 American College of Sports Medicine