Influence of physical activity on blood pressure in children with overweight/obesity. A randomized clinical trial

Abstract

Abstract Background The prevalence of childhood hypertension is growing exponentially, influenced by environmental factors such as foods with high salt content, sedentary lifestyles and poor-quality food. The incidence of hypertension is about 10.4% in well-nourished children, but when associated with obesity or overweight, this can rise to 38% and 68%, respectively. To assess the influence of physical activity on the blood pressure of children who are overweight or obese. Methods This randomised clinical trial (RCT) was carried out in Granada (Spain), from October 2015 to June 2016. The sample consisted of 98 children, all of whom were overweight or obese. The intervention group (n=49) practised physical activity and received nutritional advice, while the control group (n=49) only received theoretical-practical sessions on nutrition. Body composition was measured, a nutritional assessment was made and blood pressure was determined (in percentiles, to avoid the misclassification of children who are located at the extremes of normal growth). Results Before the physical activity intervention, 85.7% of the children in the intervention group (with overweight/obesity) were in the 95th or higher percentile for blood pressure, a situation representative of high blood pressure (hypertension). However, by the end of the study period, this value had decreased significantly (p=0.001), to 16.13%. Conclusions Childhood obesity is a risk factor for hypertension. Physical activity, together with nutritional advice, effectively reduces blood pressure in children who are overweight or obese. The use of percentiles, according to age, weight and height, is an effective means of measuring blood pressure.