Technology has made data experts of all of us, especially when it comes to exercising. Where just a few years ago most of us had no idea exactly how many steps we took in a day, how far we ran or what our pace was, wearable devices now leave this information – literally – at our fingertips.

One piece of information that stands out is your heart rate. That number alone can tell you a lot about your workout, your recovery and your general health. Exercise physiologist Chris Travers, MS, walked us through what you should know if you’re considering a heart rate monitor.

Do I need a heart rate monitor?

No, it’s not required that you bring a heart rate monitor into your workout routine. You can maintain an active, healthy lifestyle filled with exercise without one. What it comes down to is what information is important to you, especially during your workouts.

During exercise, your heart rate is a key indicator of how intense your workout is. “Maintaining a certain heart rate for a prolonged period of time can help you burn more calories and fat while also improving your cardiovascular health,” Travers says.

But it’s also possible to overexert yourself, and a heart rate monitor can alert you to that danger, too.

How heart rate monitors work

Heart rate monitors work by measuring electrical signals from your heart. They are transmitted to a wristwatch or data center. Many models let you analyze data via a computer and having that data allows you to interpret your workout and better understand the benefits from your exercise.

You can get a rough estimate by monitoring your own pulse the old-fashioned way – feeling it in your wrist or your neck – but that can be disruptive to your actual workout. An electronic heart rate monitor can give you accurate, real-time data.

Benefits of a heart rate monitor

Using a heart rate monitor during workouts lets you track key information besides just how fast your heart is beating. “When you exercise, you’re using energy,” explains Travers. “And when you’re measure your heart rate, you’re able to figure out what energy source you’re using.”

The higher your heart rate gets, the more calories you’re burning. “But,” Travers says, “the higher your heart rate is, you’re burning more carbohydrates than fat for energy because your body can’t burn fat fast enough.” By using a heart rate monitor during a workout, you can adjust your energy output to match your heart rate to the best level to burn fat.

“Developing the best cardiovascular exercise routine not only includes the amount of time you exercise, but also the intensity of the workout,” Travers notes. “Monitoring your intensity will allow you to get the optimal caloric expenditure and burning of fats and carbohydrates. A good heart rate monitor can help you monitor the intensity of your workouts.”

Heart rate zones

Using a heart rate monitor, you can figure out your current heart rate zone during exercise. First, you’ll need your maximum heart rate which you can get by subtracting your age from 220. For example, if you’re 35, your max heart rate is 185. At this point, you can figure out what heart rate zone is best for burning fat.

At 50-60% of your maximum heart rate, you’re using 85% fat to burn calories. At 60-70% of your maximum heart rate, that drops to 65% fat being used. And at 70-80%, you’re only using 45% fat to burn calories.

Different models of heart rate monitors

A heart rate monitor is a more scientific way to know how well you are doing, and it can help you keep track of your progress. While there are more devices hitting the market, including rings and bicep straps, there have been two predominant versions of heart rate monitors over the past decade: fitness trackers (which have replaced strapless wrist-based heart rate monitors) and chest strap monitors.

Fitness trackers

Fitness trackers have become quite popular over the last decade as they’re an easy way for people to track certain fitness goals like steps taken, miles run and even more detailed data like calories burned and, yes, your heart rate.

And over the years, Travers notes, technology with fitness trackers has evolved greatly, to the point where accuracy issues of the past have largely been ironed out. And as that tech has gotten better, prices of these devices have come way down, helping their popularity skyrocket.

“If you think about 8-to-10 years ago, the only people who were wearing anything like this were serious runners and they were large, somewhat unwieldy devices,” Travers says. “Now, if you look around, everyone’s wearing a fitness tracker, whether it’s an Apple Watch, a Garmin, a Fitbit or something else.”

Each fitness tracker is different and each offers a wide variety of features that may or may not be of use to you. But most now include real-time heart rate tracking which can be incredibly useful, Travers notes. Besides being able to know where your heart rate is while exercising, it can also give you information about your resting heart rate.

“It’s letting you know where you’re cardiovascular system is at, health-wise,” he adds. “The lower your resting heart rate is, the less work you heart was to do its normal daily function, which is key. The less stress on our heart to do that, the better off we are.”

“While chest strap models utilize electrodes in the padding that contacts the skin to measure the heart’s electrical activity, fitness trackers use optical sensors that measure the blood flow in your veins located below the sensor,” he says. If a fitness tracker gets out of position, it’s possible that could affect the accuracy of the data.

But the improvement in this technology still means your readings are going to be much more accurate than they were a few years ago.

Chest strap models

The most common styles consist of two components: a chest strap and a wristwatch receiver. Basic models give time and heart rate and are an open signal, Travers says.

Advanced models use a coded signal and can be used with foot pod for cadence, distance and speed. Some are equipped with GPS to mark and find locations, store previous courses as well as workouts.


  • They offer continuous heart rate information without needing to stop to measure or view it.
  • Accuracy tends to be better than the strapless models.
  • More models from which to choose.


  • Usually more expensive.
  • Basic models have open signal so interference with other monitors is possible.
  • Chest straps can be uncomfortable for some individuals.