Exercise and the heart have a symbiotic relationship. When you exercise, your heart beats faster to pump more oxygen-rich blood to your muscles. Exercise strengthens your heart and helps reduce the risk of  heart disease. It also facilitates weight loss and may help lower blood pressure.

But what happens if you have an irregular heartbeat, also called atrial fibrillation (AFib)? The electric signals that control the heartbeat don’t work like they should, so the heart may not beat in the normal “lub-dub” rhythm. Instead, it may beat too quickly or irregularly.

This chaotic rhythm makes the heart less efficient, and can result in incomplete emptying of the upper chambers. That increases the risk for a stroke or heart failure. So, should you exercise when you have AFib?

Risks and Benefits of Exercising with AFib

It can be difficult to exercise with AFib: you may feel weaker or more tired. Or, you might worry that an intense bout of running or jumping will push your heart out of rhythm. Some people with AFib find that exercise triggers their irregular heartbeat. There’s also evidence that endurance athletes, like skiers, are at greater risk for AFib.

However, exercise can be safe for people with AFib, as long as heart rhythm is kept under control. In fact, staying active strengthens the heart, reduces the risk of heart disease, and improves heart rate control. Still, it’s important to check with your doctor to make sure you’re working out within safe limits before you exercise.

Before You Start Exercising

It’s always important to check with your cardiologist before starting any workout program. This is especially true if you haven’t worked out in a while. You may need tests such as an electrocardiogram (EKG) or stress test to see if you’re ready for exercise. Your doctor might prescribe medicine to control your heart rate while you exercise.

Some people find that intense exercise can set off their AFib and make their heart race. If this happens to you, your blood pressure could drop, or you might faint—the last thing you want to happen in the middle of a workout. You might need to slow down or avoid certain high-energy activities if you find that your heart goes out of rhythm when you exercise.

Once you have the green light from your doctor, you should be able to exercise and play sports. If your doctor doesn’t feel that it’s safe for you to exercise on your own, ask if you can work out with an exercise specialist or exercise physiologist. Or, join a hospital fitness rehabilitation program for people with AFib and other heart problems.

Your Exercise Program

Work with your doctor to design an exercise program that’s safe for you. Also, ask if there are certain types of exercises you shouldn’t attempt.

Start slowly if you’re new to exercise. Do only 10 to 15 minutes of activity the first few times you exercise. Increase time and intensity only as you feel up to it. Your goal is to get 30 minutes or more of aerobic exercise three or more days per week. Alternate aerobics with two or three days of strength training each week to work your muscles.

Try these tips for exercising safely:

  • Think about how you’re feeling. Skip your workout or take it easy on days when you feel tired or out of breath.
  • Do a five- to 10-minute warm-up before each workout. Cool down for five to 10 minutes afterward to lower your heart rate slowly.
  • Take breaks often during your workout.

Stop exercising right away and call your doctor if you have any chest pain, trouble breathing, or you feel very tired.