THE INFLUENCE OF PHYSICAL ACTIVITY AND BMI ON BLOOD PRESSURE INAFRICAN-AMERICAN WOMEN

Introduction: African-American women are among those with the highest rates of obesity andhypertension, while also having low rates of physical activity (PA). While weight loss and PAhave been implicated as lifestyle factors that can reduce blood pressure, the influence of theselifestyle factors on blood pressure in African-American women is not well studied, and theexisting research has shown inconsistent findings.Purpose: To examine the relationship between the change in measures of adiposity and restingsystolic (SBP) and diastolic (DBP) blood pressure in overweight and obese non-hypertensiveAfrican-America women. In addition, this investigation will examine the influence of changes inPA and/or fitness on the relationship between the change in measures of adiposity and thechange in resting SBP and DBP.Methods: Data from 97 overweight and obese (31.4±4.0 kg/m2), non-hypertensive African-American women who participated in one of 5 weight control interventions were analyzed forthis study. The behavioral weight control interventions included dietary restriction and/or PA.Outcome measures included weight, body mass index (BMI), waist circumference, bodycomposition, PA, and fitness. The hypotheses were tested using linear regression analysis. Themediation hypothesis was tested using linear regression analysis and separately adjusting forfitness and PA.Results: There was a significant reduction in weight (5.0±5.9) systolic (4.4±10.9 mmHg), anddiastolic blood pressure (2.8±7.7 mmHg). The change in SBP was significantly correlated withchange in weight, BMI, waist circumference, and fitness, with the change in DBP significantlycorrelated with weight, BMI, waist circumference, PA and fitness. The relationship betweenmeasures of both weight and BMI and resting SBP were fully mediated by the change in eitherPA or fitness, with the relationship between change in waist circumference and change in SBPpartially mediated by the change in either PA or fitness. The relationships between DBP andmeasures of adiposity were fully mediated by the change in either PA or fitness.Conclusion: These findings highlight the potential importance of PA and fitness within thecontext of weight control for reducing resting blood pressure in overweight and obese African-American women