Exercise and the effects on blood pressure ( BP )

Regular physical activity reduces blood pressure:

• a meta-analysis by Whelton et al revealed that aerobic exercise was associated with a significant reduction in mean systolic and diastolic blood pressure:
  • systolic blood pressure reduction -3.84 mm Hg [95% CI, -4.97 to -2.72 mm Hg]
  • diastolic blood pressure reduction -2.58 mm Hg [CI, -3.35 to -1.81 mm Hg]
  • a reduction in blood pressure was associated with aerobic exercise in hypertensive participants and normotensive participants and in overweight participants and normal-weight participants
  • similar blood pressure reductions were achieved with low, moderate, and high intensity exercise and little benefit was gained from exercising for more than 2.5 hours per week

Note that previous meta-analyses have shown more dramatic effects on blood pressure reduction, which may be attributed to trials of shorter duration with better compliance or exercise supervision.

The study by Whelton et al provides further evidence that aerobic exercise of even modest duration, intensity and frequency is a useful adjunct to other lifestyle changes and antihypertensive medications in the treatment of essential hypertension.

NICE (2) note that:

• taking aerobic exercise (brisk walking, jogging or cycling) for 30-60 minutes, three to five times each week, had a small effect on blood pressure, reducing systolic and diastolic blood pressure on average by about 2-3 mmHg in trials. However, there is variation in the reduction in blood pressure achieved in trials and it is unclear why. About 30% of patients were estimated to achieve a reduction in systolic blood pressure of 10 mmHg or more in the short term, up to 1 year
• interventions actively combining exercise and diet were shown to reduce both systolic and diastolic blood pressure by about 4-5 mmHg in trials. About one-quarter of patients receiving multiple lifestyle interventions were estimated to achieve a reduction in systolic blood pressure of 10 mmHg systolic or more in the short term, up to 1 year

Reference:

1. Ann Intern Med 2002 Apr 2;136(7):493-503
2. NICE (June 2006). Management of hypertension in adults in primary care