How To Tell If Your Heart Rate Is Healthy During A Workout

An increased heart rate is normal during any kind of exercise, but is there a point when it can get too high and become dangerous?
Everyone's heart rate looks different during workouts. Here's how to know if your range is healthy or dangerous.
d3sign via Getty Images
Everyone's heart rate looks different during workouts. Here's how to know if your range is healthy or dangerous.

Between Apple Watches and Fitbits, many people keep track of their heart rate during a workout. What appears on the screen for you could be completely different from the woman next to you in an exercise class. Heart rate ranges vary from person to person, which is completely normal.

Your heart rate range should be thought of as just that: a range. There’s no perfect number, stressed Dr. Peter Robinson, an assistant professor of medicine in the division of cardiology at UConn Health Medical Center.

“In general, the harder your intensity, the more you’re working out, the higher your heart rate,” he said.

But what if you notice a quickly increasing heart rate during a run or you observe that your heart rate isn’t as high as it once was? There are reasons for both of those things. Here, experts share what to know about your heart rate when you work out:

First, it’s important to understand what a healthy heart rate is for you

When it comes to a normal heart rate during a workout, it depends completely on the type of workout and the person, said Dr. Aaron Baggish, director of the cardiovascular performance program at Massachusetts General Hospital Heart Center.

“We all have an intrinsic zone that we live in — the top number [of our heart rate] is typically dictated by our age and our gender,” he said, adding that women tend to run higher than men by 10 to 15 beats per minute and that everyone’s heart rates tend to come down slowly over time starting around age 30 or 35. (“It goes down a couple beats per year,” Baggish noted.)

So, a healthy maximum heart rate varies greatly in people. In a 70-year-old runner, their max heart rate during a workout could be 140 or 150 beats per minute (BPM). For an 18-year-old athlete, their max may be 200 BPM.

To determine your maximum heart rate, use a simple formula

Since there is no standard, normal heart rate, Dr. Danny Eapen, a preventive cardiologist at Emory Healthcare’s Center for Heart Disease Prevention, suggests you use a calculation ― known as the Fox formula ― to determine what is likely healthy for you.

To get your maximum heart rate, simply subtract your age from 220. So, if you’re 38, you’d subtract 38 from 220 to get your max heart rate — which would be about 182 BPM.

And during a workout, you can use this number as a baseline to determine how intense of a workout you’re doing, he said. According to the Centers for Disease Control and Prevention, moderate-intensity exercise is 64% to 76% of your maximum heart rate and vigorous-intensity exercise is 77% to 93% of your max.

So, for a 38-year-old, a moderate-intensity heart rate would be roughly between 116 and 138 BPM and can be achieved through brisk walking, dancing, gardening and more.

If you do 150 minutes of moderate-intensity exercise each week, you’re meeting the American Heart Association’s physical activity recommendation. Those who meet the guidelines have a lower risk of heart disease, stroke and high blood pressure — among other benefits.

But, you probably don’t want to stay in your max heart rate range for too long

Eapen added that you don’t want to keep your heart rate at its max for too long simply because you likely won’t be able to maintain it for more than a minute or two.

But, if you’re specifically training for something, you can try interval training to bring your heart rate up to (or near) its maximum and then pull back the intensity to bring your heart rate back down.

So, try running for a two-minute interval and then walking for a two-minute interval, for example. “That is the best way to help condition muscles and increase aerobic exercise capacity,” he said.

A healthy maximum heart rate decreases with age.
MStudioImages via Getty Images
A healthy maximum heart rate decreases with age.

Additionally, certain factors can cause a higher heart rate when working out

According to Eapen, if you’re dehydrated, anemic or have high thyroid levels, you may notice an increased heart rate when you exercise.

People who take a pre-workout supplement can experience this, too, in addition to folks who are just starting a fitness journey. Their heart rate may trend higher initially as their body gets used to the work, Eapen explained.

“All of [these things] can raise your baseline heart rate and sort of exacerbate the exercise-related heart rate,” he said.

A heart rate that accelerates out of nowhere is worrisome

According to Baggish, it should be cause for concern if your heart rate accelerates without a good explanation.

If you’re at a light level of work and your heart rate “goes from something you can’t feel to something that feels like it’s beating out of your chest,” you should talk to a doctor, he explained.

From there, your doctor may set you up with a heart rate monitor for your workout, which will help them determine if what you’re experiencing is worrisome. Baggish added that our own heart rate perception can be flawed, which is why monitoring from a professional is necessary before jumping to any extreme conclusions.

Additionally, Robinson added that any abrupt drop in heart rate should be addressed by a doctor, too. These abrupt drops, he noted, can happen in a matter of seconds and should trigger a conversation with a doctor.

Certain symptoms are worrisome, too

Chest tightness, extreme shortness of breath, and lightheadedness at any level of activity is concerning, Robinson said.

“That tells me you’re pushing the limits beyond [what] your heart can handle [and] outstripping your heart’s ability to compensate,” he said.

If you notice these symptoms while you work out, it might mean that you have issues with the valves in your heart or that you’re pushing too hard.

“Those are all warning signs to back off,” he said. If these symptoms go away immediately, you should just note that level of exertion was too much. But, Robinson noted, if they don’t go away or begin happening at lower levels of exertion, you need to call your doctor.

He stressed that chest pain, particularly, is a big deal. If you’re having continued chest pain, you probably want to be seen ASAP, he said. There’s a low likelihood that this will occur during or after a workout, but, if it does, you don’t want to wait to see a doctor.

Any sort of chest pain during a workout should be addressed by a doctor.
Viktorcvetkovic via Getty Images
Any sort of chest pain during a workout should be addressed by a doctor.

It’s important to know your healthy heart rate range to determine what is normal for you

A heart rate of 200 BPM may be fine for a 20-year-old but problematic for a 70-year-old, Baggish noted ― no matter what exercise they’re doing.

What’s normal for you depends on your age, your gender and what your body is used to. “It all depends on the intrinsic range that you live in,” he said. “Certainly, there can be heart rates that are above the normal range, and in that situation, that’s an arrhythmia,” which is also known as an irregular heartbeat and is something cardiologists worry about.

There is a direct relationship between how hard you’re exercising and your heart rate. It’s crucial to understand what is normal for you so you can spot a potential irregularity (like if your heart rate uncharacteristically soars the next time you’re on a leisurely walk) so you can alert your doctor, he said.

Instead of a specific heart rate number, pay attention to changes

When keeping track of your heart rate (and all aspects of your body’s health, for that matter), “change and patterns are probably more important than anything else,” Robinson said.

For example, if you always do a certain amount of exercise and notice that your heart rate is increasing a lot faster than it usually does, or you’re extremely winded after your normal workout regimen, this could be a sign that something dangerous is going on, he noted.

Change of any sort is important for doctors to know about, Robinson stressed. Reporting a change in your health patterns can sometimes be the key a doctor needs to diagnose a problem.

This is potentially even more important now as many people are faced with the reality of long COVID or a bad COVID-19 infection that absolutely impacts their usual workout routine.

Overall, know what feels best to you

An increased heart rate during a workout is normal, and just because it hits a certain number doesn’t mean you’re at risk for any complications.

What’s most important is learning to understand your healthy heart rate range and how that interacts with the exercises you do most frequently.

If you’re feeling good after a heart-pumping workout and your regular fitness expectations are in line, you’re probably fine. But, if you notice irregularities, pain or anything that doesn’t fit into your normal workout, you should contact a doctor.

Apple Watch Series 7
With detailed health features like notifications about irregular heart rhythms, sleep tracking, blood oxygen monitoring and fall detection, this watch can just about do it all. And if you’re looking to upgrade your fitness routine, it even has special sensors that track exactly how you move. Plus, your purchase will come with three free months of Apple Fitness+. You can also work out with peace of mind thanks to the watch’s crack-resistant crystal screen and water resistance. Get it in blue, red, green, black or champagne.

Promising review:
"Battery lasts all day under normal use. Very quick to charge if I do need to. My favorite features are the fitness monitoring and the ability to take an ECG. As someone with a heart condition, the peace of mind from being able to take an ECG, check blood oxygen levels, and monitor heart rate has been awesome. Pairs well with my phone and new data syncs up almost instantly. I had held off on an Apple Watch for a long time but now that I have one I wish I hadn’t waited so long." — Andrew Joyce
Fitbit Charge 5
This smartwatch connects the dots between your activity, sleep and stress to help you live a healthier life. Its health dashboard measures your heart rate, oxygen saturation, skin temperature and other important readings. The watch also records and monitors your pace as you walk, jog or run and keeps up with how far you go without having to rely on your phone, thanks to the built-in GPS.

Promising review:
"I purchased this for my dad that likes to walk. My dad has had a heart surgery and he finds it very helpful to watch his heart rate while walking. He wears it all the time and says it works great and is comfortable." — Ashley Fitzpatrick
Garmin Instinct
Calling all outdoorsy wanderers: This is the watch you need for your future excursions. It has thermal, shock and water resistance to withstand tough environments and has a built-in axis compass and barometric altimeter so you don't get lost while you're out. You can also monitor your heart rate, activity while you're moving and stress levels.

Promising review: "Perfect to keep track of my sleep patterns, watch my heart rate while on hunts due different elevations, and having the ability to re trace my steps and get back to camp is perfect. Batteries usually last me about 10 days between charges." — Taira Goy
Fitbit Versa 2
If you want to get a better idea of your sleep quality and heart health, this Fitbit is the watch for you. It tracks how long you catch Zzz's and your heart rate while you're slumbering to give you a sleep score to understand your sleeping habits. But even when you're not sleeping, it monitors your heart rate 24/7 (or as long as you wear it), the number of steps you take, distance, calories burned and more.

Promising review:
"Got this for my girlfriend to help her track and manage her anxiety. Between the heart rate monitor and built-in breathing/relaxing exercises, she says it has been a huge help and has enabled her to see when she is becoming anxious before she even realizes it and helps her to calm herself down. Lastly, it makes her more excited to work out because she likes seeing/tracking her progress. Definitely a great purchase!" — Pierce Carnell
Samsung Galaxy watch
For a truly intuitive option that knows your body, look no further than this Samsung watch. It gives you readings on body fat, skeletal muscle, body water, body mass index and more. And of course, it gives detailed information on your heart health. One feature you'll want to use immediately is the accurate ECG monitoring, which provides insight on irregular heart rhythms that you can discuss with your doctor. To use it, a Samsung Galaxy smartphone with Android 7 or later is required.

Promising review:
"It looks good with high definition, battery life approx 40 hours after a full charge, tracks exercise quite accurately as well as measuring heart rate. It is light weight, can't feel any heat on my wrist, and bands does not seem sticky. During walking and running, it measured multiple datas including almost real-time heart rate. It's been fun to exercise with this watch. In my opinion, there's no doubt if you own a Samsung smartphone, this is the best watch on the market." — Spoly