Heart Rate and Exercise: How Much Do You Know?

Your target heart rate tells you if you're exercising too hard or not hard enough. Everyone's target is different, but in general, during moderate or vigorous exercise, you want it to be between 50% and 85% of your maximum heart rate, which is the hardest your heart can work safely.

This is the fastest your heart can beat during physical activity. Like your target heart rate, your maximum heart rate is an estimate. If you feel like you can’t breathe or talk, or you get dizzy while exercising, that’s a sign you’re overdoing it. Slow down. You may be at risk of hurting your heart.

If you raise your heart rate much past 90% of its maximum, you could strain it. But with regular exercise you can strengthen it, allowing you to reach greater heights.

Wearable electronic heart monitors, and exercise machines with built-in heart sensors, can give you up-to-the-minute information on how hard your heart is working. That can tell you how hard you’re exercising. It can help you pace yourself, too. It may even help keep you motivated.

They aren’t a necessity unless your doctor says so, but they can help you get the most out of exercise.

If you have a heart condition or other medical problem, your doctor may ask you to monitor it during exercise to make sure you don’t push your heart too hard. But even if you're healthy, you may want to keep an eye on it (say, every 5 to 10 minutes, or when you increase your intensity). It will help you know how hard you’re working and if you’re keeping your heart safe.

This kind of exercise involves switching between low- or moderate-intensity exercise and bursts of vigorous exercise. One way to figure out how hard to exercise during each interval is to monitor your heart rate. During low to moderate periods, it should be about half of your maximum heart rate. During vigorous exercise, shoot for 70% to 85%.

Exercise strengthens your heart. That means it doesn’t have to work as hard to push blood through your body, which lowers your resting heart rate. A lower resting heart rate is linked to a longer life. Book some time in the gym and make your heart more efficient.