Physical activity plays key role in controlling blood pressure

One of the most important things you can do for your blood pressure is to become more active. Physical activity can help prevent the development of high blood pressure and can help keep it under control if your blood pressure is already high.

A major reason high blood pressure is so common — one in four American adults has it — is that people aren't active enough. Modern conveniences and lack of time foster sedentary lifestyles. About one-quarter of adults are sedentary, and only about 15 percent regularly get enough exercise to gain any health benefits.

The benefits of staying active

Whether you're older, younger, overweight or not, physical activity can reduce your blood pressure. That, in turn, can reduce your risks of the myriad health complications associated with high blood pressure, including stroke, heart failure, dementia, kidney disease and vision loss.

Physical activity is crucial to controlling your blood pressure because it makes your heart stronger. A stronger heart can pump more blood more efficiently. And the less your heart has to work, the less force, or pressure, that's exerted on your arteries. There's also some evidence that exercise decreases the body's release of norepinephrine, a hormone that raises blood pressure by constricting arteries and increasing heart rate. And exercise may also improve the condition of arteries and veins, which can enhance blood flow.

Normal blood pressure is less than 120/80 millimeters of mercury (mm Hg). Hypertension begins at readings of 140/90 mm Hg. Becoming more active can lower your blood pressure by as much as 4 to 9 points. That could mean the difference between having high blood pressure and not having it. And it's the same reduction in blood pressure delivered by some antihypertensive medications — but without the side effects.

Regular physical activity also helps you maintain a normal weight or lose excess pounds. Weight loss can have a powerful impact on blood pressure, reducing it by as much as 20 points. In fact, once you get moving, you might even be able to reduce some of your blood pressure medications — just talk to your doctor before making any changes.

In addition, physical activity may help prevent preeclampsia, a serious problem in some pregnancies. Preeclampsia is a rare, life-threatening condition that may develop after the 20th week of pregnancy and that is primarily characterized by high blood pressure and the presence of protein in the urine (proteinuria). Women who regularly participate in physical activity during the first five months of pregnancy or in the year before pregnancy may reduce their risk of preeclampsia. Talk to your doctor first to make sure exercise is safe for you.

No pain, no problem

The motto of physical fitness used to be "No pain, no gain." Many people thought they had to transform themselves into world-class athletes or spend hours in the gym each day to truly benefit from physical activity.

But no more. You don't need to perform great feats of endurance to reap the benefits of exercise. Simply adding some moderate physical activities to your daily routine will help.

Moderate is the key, though. Activities or chores that aren't at least moderately exerting will offer little, if any, benefit. Just what is moderate activity? Any activity that you think is fairly light to somewhat hard to perform. For instance, slow walking may not be enough. Walking to the point of breathlessness may be overdoing it. Find a pace in between that's comfortable yet requires some effort.

Some examples of moderate-level activity:

Raking leaves for 30 minutes

Shoveling snow for 15 minutes

Wheeling yourself in your wheelchair for 30 to 40 minutes

Water aerobics for 30 minutes

Swimming laps for 20 minutes

Running 1 1/2 miles in 15 minutes (10 minutes per mile)

Walking 2 miles in 30 minutes (15 minutes per mile)

Dancing fast for 30 minutes

Moderate activity shouldn't cause discomfort. Your breathing might be increased and you should feel as though you're working. But you shouldn't feel pain or experience exhaustion. Keep in mind that some medications used to treat blood pressure, such as beta blockers and certain calcium antagonists (calcium channel blockers), can affect your heart rate during exercise. You may feel shorter of breath at lower heart rates. Your doctor can help you understand how to monitor your heart rate during exercise based on your situation and the medications you're taking.

Types of activity

Total fitness involves three components: aerobic activity to improve your heart and lung capacity (cardiovascular health), flexibility exercises to improve flexibility in your joints, and strengthening exercises to maintain bone and muscle mass.

Of those three, aerobic, or endurance, activity is the best at controlling high blood pressure and improving cardiovascular health. An activity is aerobic if it places added demands on your heart, lungs and muscles, increasing your need for oxygen. These are activities that exercise large muscle groups, such as those in the legs. Cleaning house, playing golf or raking leaves are all aerobic activities if they require a fairly light to somewhat hard effort.

Other common forms of aerobic activity:

Walking

Jogging

Bicycling

Swimming

Exercise machines, including stationary bikes, treadmills, rowing machines, stair climbers and ski machines

Strengthening exercises, or resistance training, with weights can supplement your aerobic activity. But be careful not to strain while performing strength training since that could increase your blood pressure. Stretching, yoga or other gentle muscle work can improve flexibility. Don't do strenuous, prolonged isometric exercises — straining of your muscles without moving. Isometrics can significantly increase your blood pressure during exercise and for a short time afterward.

Before starting an exercise program

For most people, it's not necessary to visit the doctor before starting an exercise program of moderate intensity. But if you have high blood pressure, you may need to. A thorough evaluation can check for complications you may not be aware of, such as heart or kidney disease.

Here are a few things to bear in mind:

See your doctor first if you're 50 or older and have never exercised, if you smoke or if you're overweight. See a doctor first, too, if you have a chronic health condition, such as diabetes, have a family history of heart-related problems at an early age, or are unsure of your health status. Also check with your doctor first if you have previously had chest discomfort, shortness of breath or dizziness when exerting yourself, or if you have any heart conditions.

If your blood pressure is severe or not well controlled, check with your doctor before starting an exercise program.

If you take medication regularly, ask your doctor if increased activity will make it work differently or alter its side effects. Drugs for diabetes and cardiovascular disease can sometimes cause dehydration, impaired balance and blurred vision. Some medications can also affect the way your body reacts to exercise. Certain types of blood pressure medication can impair the ability to regulate body temperature, which could pose a health risk during exercise, especially in hot or humid conditions.

If you check your own blood pressure, measure it before physical activity, not after, to ensure an accurate reading. That's because aerobic activity can keep your blood pressure lower for many hours afterward.

Know the warning signs and symptoms that require immediate medical attention. They include tightness in your chest, severe shortness of breath, chest pain or pain in your arms or jaw, fast, irregular heartbeats (palpitations), and dizziness, faintness or nausea.

Fitting it in

To gain the most benefits, the goal is to engage in moderate-intensity physical activity 30 to 60 minutes a day most days of the week. If you're out of shape or not used to exercising, you may have to work up to this goal gradually. Start by exercising for shorter periods of time just two or three days a week and build up. On the other hand, if you're already getting in 30 minutes a day, try to gradually increase to 60 minutes or — if your doctor has OK'd it — increase the intensity of your workouts.

If it's hard to carve out a 30-minute or 60-minute block of time in your schedule, try to do a series of 10-minute sessions throughout the day to meet your cumulative goal. Park your car a bit farther away from work. Take a short walk during your lunch break. Sneak in some household chores while the baby's playing. Three 10-minute periods of activity are almost as beneficial to your overall fitness as one 30-minute session.

Over time, you may find it's less of a chore to fit exercise into your daily routine. And improvements you see in your blood pressure control may offer even more motivation to stick with it.