Objective: To test the hypothesis that in young, normotensive obese subjects, physical activity at a fixed, moderate workload, causes a more pronounced hypertensive effect than in lean subjects.
Patients and methods: 24 subjects (12 with BMI >30 kg/m(2), 12 with BMI <25 kg/m(2)), underwent a moderate-intensity physical activity protocol (cycling at 100 W). Blood pressure and oxygen consumption were monitored continuously.
Results: In the obese subjects, physical activity caused a more pronounced increase in both systolic blood pressure (increase of 40.4 +/- 15.3 mmHg vs 21.2 +/- 10.2 mmHg in lean subjects; p=0.001) and diastolic blood pressure (17.5 +/- 17.9 mmHg vs 3.2 +/- 8.1 mmHg in lean subjects; p=0.02). In regression analyses, these differences were only partly explained by small differences in resting blood pressure.
Conclusion: Healthy obese subjects show an enhanced prohypertensive response of both systolic and diastolic blood pressure to moderate-intensity physical activity.