About one in three adults in the United States has high blood pressure--nearly 74.5 million people in all, according to the American Heart Association. High blood pressure can lead to a stroke, heart attack or congestive heart failure. Being physically active is one of the most important things you can do to control your blood pressure, according to the National Heart Lung and Blood Institute.
Expert Insight
A study reported in the "Journal of Strength and Conditioning Research" reported that study participants who engaged in 20 minutes of aerobic exercise every day--running on a treadmill--experienced lower blood pressure for seven hours after the exercise. The authors of the study recommend adding regular, moderately intense aerobic exercise as part of the overall treatment for high blood pressure.
Effects
Blood pressure is the force of blood against the walls of the arteries. Arteries that are hard and can't expand easily provide resistance when the heart beats, making blood pressure higher. Running helps keep your arteries elastic, according to the Mayo Clinic. As you run, your arteries expand and contract more than usual, making them more flexible so that they provide less resistance to increased blood flow. Normal blood pressure is between 90/60 and 120/80. The first number is the pressure when the heart contracts and empties, and the second number represents the amount of pressure inside the arteries when the heart rests between contractions. If your resting blood pressure remains above 120/80, your heart may be working too hard and you are at greater risk for stroke, heart attack or artery disease.
Considerations
While you are exercising, your blood pressure may temporarily increase. If you have severe high blood pressure, your doctor may tell you to take your blood pressure medication an hour or so before exercising to avoid that spike in blood pressure. It's possible to reduce your blood pressure with as little as four weeks of regular, moderately intense running. However, you have to keep exercising. If you give up exercising, you can revert to having higher blood pressure again.
Recommendations
The University of Mexico recommends moderately intense aerobic exercise for 30 to 45 minutes a day, most days of the week. They define moderately intense as being 40 to 60 percent of the maximum aerobic capacity, which is the point at which you pass from aerobic to anaerobic exercise, leading to exhaustion. Therefore, running at about half your maximum capacity would be considered moderately intense. As you become more fit, your oxygen capacity increases and you can increase the intensity of your exercise.
Theories/Speculation
Experts theorize that some of the benefit of aerobic exercise is related to epinephrine and norepinephrine, hormones that cause arterioles to decrease in diameter. Aerobic exercise lowers the blood level of norepinephrine, so that arteries are more relaxed and flexible. Because they are more able to stretch in response to blood flow, blood pressure goes down.
References
- MayoClinic.com: Exercise: A drug-free approach to lowering high blood pressure
- "Journal of Strength and Conditioning Research"; Effects of Treadmill Running and Resistance Exercises on Lower Blood Pressure; Mota, M.R. et al.; Nov. 2009
- University of New Mexico; Exploring the Mysteries of Exercise; Len Kravitz, Ph.D.
- State University of New York at Buffalo: Exercises for Hypertension
- University of Southern California Health Magazine: Just Doing It
- University of New Mexico; Exercise and Resting Blood Pressure; Len Kravitz, Ph.D.
