UT Southwestern Medical Center researchers have identified one reason people with hypertension experience an even greater increase in their blood pressure when they exercise, and they've learned how to prevent the rise. Show A study in a March issue of the Journal of Physiology reported that hypertensive people who exercise undergo decreased blood flow and oxygen in muscles. The scientists also identified a specific type of blood pressure medication that minimizes this effect. "While there are many hypertension medications effective at lowering blood pressure at rest, very few are effective during exercise," said Dr. Wanpen Vongpatanasin, associate professor of internal medicine at UT Southwestern and lead author of the study. "People with high blood pressure need to exercise not only to help their blood pressure, but also their overall cardiovascular health." Dr. Vongpatanasin said that some people with high blood pressure stop exercising out of fear of heart attack or stroke, and that sometimes physicians counsel those patients to limit activity because of those concerns. While it's been known that blood pressure increases during exercise in people with hypertension, a mechanism behind the action and a way to block it in humans hadn't been identified previously. Dr. Vongpatanasin and colleagues had 13 participants with mild hypertension and 13 with normal blood pressure perform hand grip exercises under regular conditions, followed by activity under conditions that affect a part of the nervous system that controls blood pressure. They found increased nerve activity in hypertensive participants during exercise but not in those with normal blood pressure. Blood flow and oxygen levels in the arm muscles also fell more rapidly in the hypertensive group. "In normal people, the body can increase blood flow to the working muscle despite increase in nerve activity, which tends to cause blood vessels to constrict," Dr. Vongpatanasin said. "Hypertensive patients have increased nerves and impaired ability to maintain muscle blood flow adequately." Researchers then treated study participants with two types of blood pressure medications. An angiotensin receptor blocker, which prevents the hormone angiotensin from increasing blood pressure, increased blood flow during exercise. A diuretic that reduces blood pressure by stimulating sodium loss did not. "Since nerve increases weren't reduced during treatment, we believe the angiotensin receptor blocker works directly on blood vessels to improve blood flow," Dr. Vongpatanasin said. The next step, she said, will be to see if other hormones associated with angiotensin are involved in similar responses. Other UT Southwestern researchers involved in the study were Zhongyun Wang, research associate in internal medicine; Debbie Arbique, advanced practice nurse in internal medicine; Dr. Gary Arbique, associate professor of radiology; Beverley Adams Huet, assistant professor of clinical sciences; and Dr. Jere Mitchell, clinical professor of internal medicine and physiology. Researchers from Cedars-Sinai Medical Center also participated. The study was funded by the National Institutes of Health, the National Institute of Diabetes and Digestive and Kidney Diseases' George M. O'Brien Kidney Research Core Center at UT Southwestern and a Clinical and Translational Sciences Award from the National Center for Research Resources. Story Source: Materials provided by UT Southwestern Medical Center. Note: Content may be edited for style and length. Blood pressure after exercise Exercise can increase blood pressure, but the effects are typically temporary. Your blood pressure should gradually return to normal after you finish exercising. The quicker your blood pressure returns to its resting level, the healthier you probably are. According to guidelines provided by the Centers for Disease Control and Prevention, “normal” blood pressure is less than 120/80 mm Hg. This includes a systolic pressure reading under 120 mm Hg (the top number) and a diastolic pressure reading (the bottom number) under 80 mm Hg. Exercise increases systolic blood pressure. Systolic blood pressure is a measure of blood vessel pressure when your heart beats. Diastolic blood pressure is a measure of the pressure in the blood vessels between heartbeats. It shouldn’t change significantly during exercise. If it does, consult your doctor. It’s difficult to say conclusively what blood pressure readings are considered healthy after exercise, as blood pressure varies from person to person. Normal levels for one person might be a sign of a problem for another person. In general, though, high blood pressure after a resting period of up to two hours following exercise includes any reading greater than 140/90 mm Hg. Low blood pressure after exercise includes any reading lower than 90/60 mm Hg. Aerobic activities such as swimming, cycling, and running put additional demands on your cardiovascular system. Your muscles need more oxygen than they do when you’re at rest, so you have to breathe more quickly. Your heart starts to pump harder and faster to circulate blood to deliver oxygen to your muscles. As a result, systolic blood pressure rises. It’s normal for systolic blood pressure to rise to between 160 and 220 mm Hg during exercise. Unless you’ve cleared it with your doctor, stop exercising if your systolic blood pressure surpasses 200 mm Hg. Beyond 220 mm Hg, your risk of a heart problem increases. Different factors can influence how your cardiovascular system responds to exercise. Some of these factors include diet, medical conditions, and medications. For instance, exercise hypertension is a condition that causes an extreme spike in blood pressure during physical activity. People with exercise hypertension can experience spikes in systolic blood pressure up to 250 mm Hg during exercise. In general, your blood pressure should return to normal within several hours of a workout. Even then, you might notice that your blood pressure doesn’t return to exactly what it was before exercise. That’s because it’s normal for blood pressure to drop slightly within a few hours of exercise. It’s safe to exercise if you’re at risk for high blood pressure (previously called prehypertension) or with high blood pressure (hypertension). In fact, regular exercise can help you keep your blood pressure in check. If you’re at risk for or have hypertension, speak to your doctor about the safest way to exercise. This may involve:
If you’re concerned about your blood pressure, you can monitor it before, during, and after your workout. Also check with your doctor before starting a new exercise program if you have low blood pressure (hypotension). Exercise — especially exercise that involves sudden changes in posture — can trigger symptoms, including dizziness, blurred vision, and nausea. That doesn’t mean you shouldn’t exercise if you have low blood pressure. In fact, exercise can also be beneficial in treating hypotension, as it helps improve blood circulation. If you have low blood pressure, opt for moderate activities that don’t involve bending and rising quickly to an upright position. A spike or drop in blood pressure during exercise can be a sign of a medical condition. Blood pressure spikesA dramatic increase in blood pressure during or after exercise could be a sign of:
If your blood pressure rises quickly to a reading of 180/120 mm Hg or greater, seek emergency medical attention. Unmonitored blood pressure in this range can be a sign of a heart attack or stroke. Blood pressure dropsSignificant drops in blood pressure after exercise are a risk factor for developing or having hypertension and having certain types of heart disease. While most people experience a slight drop in blood pressure following exercise, research suggests that people with hypertension experience more significant decreases in blood pressure. Speak to your doctor if you notice any of the following:
In general, if you’re worried about your blood pressure, make an appointment with your doctor. Exercise can help regulate blood pressure. If you have hypotension or are at risk for or have hypertension, the following tips can help you improve safety:
It’s normal for blood pressure to rise during exercise. However, extreme spikes or drops in blood pressure can be a sign of a medical condition, such as being at risk for or having hypertension. It’s usually safe to exercise even if you have low or high blood pressure. In fact, exercise can help you keep your blood pressure in check. Speak to your doctor with your questions about exercise and blood pressure. What exercises should be avoided with high blood pressure?If you have high blood pressure, you should avoid physical activity that requires sudden bursts of activity or strain as these may increase the risk of arterial rupture, heart attack, or stroke. Activities to avoid include weight lifting, playing squash, and sprinting, as well as skydiving and SCUBA diving.
Should I exercise if my blood pressure is extremely high?And if your blood pressure is already high, exercise can help you control it. Don't think you need to immediately run a marathon or join a gym. Instead, start slow and work more physical activity into your daily routine.
What blood pressure is too high during exercise?It's normal for systolic blood pressure to rise to between 160 and 220 mm Hg during exercise. Unless you've cleared it with your doctor, stop exercising if your systolic blood pressure surpasses 200 mm Hg. Beyond 220 mm Hg, your risk of a heart problem increases.
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Is it dangerous to exercise with high blood pressure
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