Dose-response relation between physical activity and blood pressure in youth.
ABSTRACT The dose-response relationship between physical activity (PA) and cardiovascular health in children and adolescents is unclear. Blood pressure (BP) is a practical and useful measure of cardiovascular health in youth.
This study aims to examine the dose-response relationship between objectively measured PA and BP in children and adolescents.
The sample included 1170 youth aged 8-17 yr from the 2003/04 U.S. National Health and Nutrition Examination Survey. PA was measured using Actigraph accelerometers (Ft. Walton Beach, FL, USA) over 7 d. Thresholds of 2000 and 3000 counts per minute were used to denote those minutes where the participants were engaged in total PA and moderate-to-vigorous intensity PA, respectively. BP was measured using standard procedures. Systolic and diastolic BP values were adjusted for age, height, and sex. Participants with adjusted BP values > or = 90th percentile were considered to have hypertension. Thirty-six fractional polynomial regression models were used to obtain the dose-response curve that best fit the relation between PA with systolic BP, diastolic BP, and hypertension.
Inverse dose-response relations were observed between total and moderate-to-vigorous PA with systolic and diastolic BP. The slopes of the curves were modest indicating a minimal influence of PA on mean BP values. The likelihood of having hypertension decreased in a curvilinear manner with increasing minutes of PA. At 30 and 60 min.d of moderate-to-vigorous PA, the odd ratios (95% confidence intervals) for hypertension were 0.50 (0.28-0.64) and 0.38 (0.17-0.52), respectively, in comparison to no PA.
A modest dose-response relation was observed between PA and mean systolic and diastolic BP values. PA did, however, have a strong gradient effect on BP when predicting hypertensive values. These results support the public health recommendation that children and youth accumulate at least 60 min of moderate-to-vigorous PA daily.
SourceAvailable from: Kelli L Cain
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ABSTRACT: Background Children with cerebral palsy (CP) participate in reduced levels of physical activity and spend increased time in sedentary behavior. The effect of this on their cardiometabolic health has not been investigated.Objectives The purpose of this study was to investigate the prevalence of overweight/obesity and elevated blood pressure (BP) among a cohort of ambulatory children with CP. Secondly, the aim was to investigate the association between physical activity, sedentary behavior, overweight/obesity and BP in children with CP.Study designThis was a cross-sectional study of 90 ambulatory children, age 6 to 17 years, with CP.Methods Body mass index (BMI), waist circumference, waist-height ratio and BP were measured on one occasion. Habitual physical activity was measured by accelerometry over 7 days.ResultsThe prevalence of overweight/obesity in the cohort was 18.9%. Twenty-two percent of children had BP values within the hypertensive or pre-hypertensive range. Systolic BP was positively associated with waist circumference (β = 0.324, p <0.05) and BMI (β = 0.249, p<0.05). Elevated BP values were associated with reduced time in moderate-to-vigorous activity, vigorous activity and total activity, and increased time in sedentary behavior. The strongest association was observed between elevated BP and vigorous activity alone (odds ratio, 0.61; 95% confidence interval, 0.37-0.99; p <0.05).LimitationsA convenience sample was recruited for this study and it is possible that this resulted in selection bias.Conclusions Despite the relatively low prevalence of overweight/obesity, a relatively high proportion of children with CP had elevated BP values. Reducing sedentary behavior and increasing habitual physical activity, particularly vigorous activity, should be a primary aim of rehabilitation in order to reduce cardiometabolic disease risk in this population.Physical Therapy 04/2014; 94(8). DOI:10.2522/ptj.20130499 · 3.25 Impact Factor
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ABSTRACT: This study aimed to investigate the effects of training on health-related quality of life (HRQoL), body composition, and function in older adults. Fifty participants were randomized into aerobic training (AT-70%-80% HRreserve), resistance training (RT-80% 1RM), or controls. They had HRQoL, body composition, and function assessed before and after 8 months. Training groups reduced body fat, increased performance in the stair ascent, 8-ft up-and-go and sit-to-stand five-times tests, and improved their physical component score (PCS; p ≤ .03). AT increased performance in the 6MWT test, and improved general and mental health (MH) domains when compared to controls (p < .01). Finally, changes in stair ascent were associated with changes in bodily pain, MH, and mental component score (p ≤ .04), while changes in handgrip strength were associated with changes in physical role and MH (p = .03). AT and RT were effective interventions for decreasing body fat and improving functionality and the PCS in older adults.01/2013; DOI:10.1177/0733464812468502