Your risk of high blood pressure (hypertension) increases with age, but getting some exercise can make a big difference. And if your blood pressure is already high, exercise can help you control it. Don't think you've got to run a marathon or join a gym. Instead, start slow and work more physical activity into your daily routine.

How are high blood pressure and exercise connected? Regular physical activity makes your heart stronger. A stronger heart can pump more blood with less effort. If your heart can work less to pump, the force on your arteries decreases, lowering your blood pressure.

Becoming more active can lower your systolic blood pressure — the top number in a blood pressure reading — by an average of 5 to 10 millimeters of mercury (mm Hg). That's as good as some blood pressure medications. For some people, getting some exercise is enough to reduce the need for blood pressure medication.

If your blood pressure is at a desirable level — less than 120/80 mm Hg — exercise can keep it from rising as you age. Regular exercise also helps you maintain a healthy weight, another important way to control blood pressure.

But to keep your blood pressure low, you need to keep exercising. It takes about one to three months for regular exercise to have an impact on your blood pressure. The benefits last only as long as you continue to exercise.

Flexibility and strengthening exercises such as lifting weights are an important part of an overall fitness plan, but it takes aerobic activity to control high blood pressure. And you don't need to spend hours in the gym every day to benefit. Simply adding moderate physical activities to your daily routine will help.

Any physical activity that increases your heart and breathing rates is considered aerobic. Mowing the lawn, raking leaves or scrubbing the floor counts — as long as it takes effort. Other common forms of aerobic activity include climbing stairs, walking, jogging, bicycling and swimming.

Aim for at least 30 minutes of aerobic activity most days of the week. If you can't set aside that much time at once, remember that shorter bursts of activity count, too. Try taking the stairs instead of the elevator or taking a walk during your lunch break.

Sometimes it's best to check with your doctor before you jump into an exercise program, especially if:

• You're a man older than age 40 or a woman older than age 50
• You smoke
• You're overweight or obese
• You have a chronic health condition, such as high blood pressure or high cholesterol
• You've had a heart attack
• You have a family history of heart-related problems before age 55
• You feel pain in your chest or become dizzy with exertion
• You're unsure if you're in good health

If you take any medication regularly, ask your doctor if exercising will make it work differently or change its side effects — or if your medication will affect the way your body reacts to exercise.

To reduce the risk of injury while exercising, start slowly. Remember to warm up before you exercise and cool down afterward. Build up the intensity of your workouts gradually.

If you'd like to try strength training exercises, make sure you have your doctor's OK. Some of these exercises may increase your blood pressure — especially if you hold your breath while contracting your muscles.

Stop exercising and seek immediate medical care if you experience any warning signs during exercise, including:

• Chest pain or tightness
• Dizziness or faintness
• Pain in an arm or your jaw
• Severe shortness of breath
• An irregular heartbeat
• Excessive fatigue

The only way to detect high blood pressure is to keep track of your blood pressure readings. Have your blood pressure checked at each doctor's visit, or use a home blood pressure monitor. If you already have high blood pressure, home monitoring can let you know if your fitness routine is helping to lower your blood pressure, and may make it so you don't need to visit the doctor to have your blood pressure checked as often. If you decide to monitor your blood pressure at home, you'll get the most accurate readings if you check your blood pressure before you exercise, or at least one hour after exercising.