Martinez-Gomez David, Tucker Jared, Heelan Kate A, Welk Gregory J, Eisenmann Joey C
Department of Kinesiology, Iowa State University, Ames, Iowa, USA.
Arch Pediatr Adolesc Med. 2009 Aug;163(8):724-30. doi: 10.1001/archpediatrics.2009.90.
To examine the effect of sedentary behavior on blood pressure (BP) in young children using different indicators of sedentariness.
Cross-sectional study.
A rural Midwestern US community.
Children aged 3 to 8 years (N = 111). Intervention Adiposity was assessed using dual energy x-ray absorptiometry. Objective measurements of sedentary activity were obtained from the accelerometers that participants wore continuously for 7 days. Measurements of television (TV) viewing, computer, and screen time (TV + computer) were obtained via parent report.
Systolic and diastolic BP.
The sample spent a mean of 5 hours per day in sedentary activities, of which 1.5 hours were screen time. Accelerometer-determined sedentary activity was not significantly related to systolic BP or diastolic BP after controlling for age, sex, height, and percentage of body fat. However, TV viewing and screen time, but not computer use, were positively associated with both systolic BP and diastolic BP after adjusting for potential confounders. Participants in the lowest tertile of TV and screen time had significantly lower levels of systolic and diastolic BP than participants in the upper tertile.
Sedentary behaviors, particularly TV viewing and screen time, were associated with BP in children, independent of body composition. Other factors that occur during excessive screen time (eg, food consumption) should also be considered in the context of sedentary behavior and BP development in children.
使用不同的久坐行为指标来研究久坐行为对幼儿血压（BP）的影响。
横断面研究。
美国中西部的一个农村社区。
3至8岁的儿童（N = 111）。干预措施 使用双能X线吸收法评估肥胖情况。通过参与者连续佩戴7天的加速度计获得久坐活动的客观测量数据。通过家长报告获得看电视、使用电脑和屏幕时间（电视+电脑）的测量数据。
收缩压和舒张压。
样本每天平均花费5小时进行久坐活动，其中1.5小时为屏幕时间。在控制年龄、性别、身高和体脂百分比后，加速度计测定的久坐活动与收缩压或舒张压无显著相关性。然而，在调整潜在混杂因素后，看电视和屏幕时间与收缩压和舒张压均呈正相关，但使用电脑与血压无此关联。处于看电视和屏幕时间最低三分位数的参与者的收缩压和舒张压水平显著低于处于最高三分位数的参与者。
久坐行为，尤其是看电视和屏幕时间，与儿童血压相关，且独立于身体成分。在儿童久坐行为和血压发展的背景下，还应考虑在过多屏幕时间内发生的其他因素（如食物摄入）。
