Wearable activity trackers make it easy—and fun—to go down a rabbit hole of heart rate statistics. You can easily see how your heart rate changes by the second, view graphs of your resting heart rate over time, and even analyze your sleep.
But what do all those statistics tell you about your health? Is your heart rate throughout the day “normal” or “good”? And when does your pulse rate indicate that something’s not quite right?
Ami Bhatt, MD, a Mass General Brigham cardiologist, researcher and the director of Massachusetts General Hospital’s Adult Congenital Heart Disease Program, has answers to all of your questions.
The genesis of a heartbeat starts with a group of cells (the sinoatrial node) that sends an electrical signal through the heart, down two information highways called bundle branches. These branches go to the right and left sides of the heart and signal the heart to squeeze.
Your heart rate refers to how often that squeeze happens. Abnormalities in your heart rate can happen anywhere along this electricity route.
You can measure your heart rate a number of ways, even without an activity tracker. Simply press three fingers over your radial artery (where your thumb meets your wrist). Count how many beats you feel in 15 seconds and multiply that number by four.
“Heart rates vary significantly, but most people’s hearts run between 60 and 100 beats per minute at rest,” says Dr. Bhatt. “Kids will have a higher heart rate at baseline than adults. Athletes may have a lower heart rate because of their training.”
This number fluctuates throughout the day. Maybe you’re sitting and reading—you feel relaxed and your heart rate slows. Other times, you feel excited or anxious—or maybe you just ran to catch a bus—and your heart beats faster.
Other factors influence your heart, too. Your pulse may change due to:
Dr. Bhatt stresses that “normal” and “good” are relative terms. “Everybody has their own resting heart rate that can change over time,” she says. “We rarely say ‘this is a normal heart rate’ because we don’t want people to worry.”
A good heart rate for you depends on your body and your situation. Let’s say you get in better shape and your resting heart rate goes down—that might be a good thing. A lower resting heart rate can mean your body’s autonomic nervous system is more balanced and adaptable to situations you encounter every day. But if you're getting older and you're lightheaded or fainting with a low heart rate, that might be a sign that something is wrong.
The bottom line? “It's important to know your own resting heart rate and how it changes throughout the day,” emphasizes Dr. Bhatt. “Being outside of your own range and feeling unwell generally means something’s not right.”
So, when should you pay attention to your heart rate? Dr. Bhatt highlights the two main causes for concern:
A heart palpitation (arrhythmia) is when your heart feels like it’s beating too quickly, skipping beats, fluttering or pounding. Palpitations happen when the heart’s electrical signals fire abnormally.
Palpitations don’t necessarily pose a danger, but you should tell your doctor if you think your heart rate feels different. Your doctor can examine and monitor your heart to figure out the cause.
“If you feel unwell at the same time you notice your heart rate doing something strange—that’s the combination we worry about,” says Dr. Bhatt. Concerning symptoms include:
Although it’s great to know your heart rate, it’s really important not to overanalyze things. “We can just make ourselves feel worse and create unnecessary anxiety,” Dr. Bhatt says.
“The most important thing people can do when it comes to maintaining a healthy heart rate is some level of regular aerobic exercise,” she adds. That exercise may include walking, biking, arm exercises—whatever you can do to increase your heart rate a few times a week.
In addition, Dr. Bhatt recommends:
“Once you're doing those things, you'll find that it will be nice to know your heart rate, and it might be interesting,” says Dr. Bhatt, “but it won't be worrisome because you'll know that you’re being healthy.”