The best heart rate monitors are those that you can easily forget you're wearing, while gaining consistent, accurate and insightful data. The humble heart rate monitor can provide insight into training effort, exertion, fatigue and more.
They range from lightweight chest straps to small optical wristbands that track your pulse. The latter is now used in fitness trackers and smartwatches at all price points. Each option can map other metrics like heart rate viability, remember workout data, and even determine cadence.
Here’s our pick of the best heart rate monitors available today, and if you're unsure what separates a good heart rate monitor from a bad one, here’s what to look for.
Things to look out for
ECG or LED
The classic heart-rate chest strap uses sensors pressed up against your skin to measure the electrical impulses that control the contraction and expansion of the muscles in your heart (ECG). In contrast, optical sensors shine light through your skin (LED) and measure the variance in blood flow.
Even with significant advances in technology, the classic ECG based chest strap still reigns supreme in terms of accuracy.
Optical sensors need to maintain consistent contact with your skin for an accurate reading, but bumps, jumps, and even muscle tension from gripping your handlebars can stymie the sensor. With the contact required, optical sensors come with precise fit instructions; constant shaking on your arm from road imperfections and sweaty sunscreen-covered skin can cause them to slide around enough to impede accuracy.
In our experience, a chest strap offers far superior point-to-point accuracy, however, the optical sensors are still pretty good at determining trends in heart rate.
Most of today's smartwatches have a built-in optical sensor, and some can even connect to your head unit to serve as a sensor.
As with speed/cadence sensors and power meters, heart-rate sensors can connect to devices with ANT+ or Bluetooth, with most options now doing both. Which is right for you largely depends on the devices you'll be connecting.
Most GPS head units will support, at the very least, ANT+ or Bluetooth with the majority speaking both languages — if you're looking to save a few bucks pick a heart-rate strap that only does one (just make sure it's the right one).
If you're looking to use a cycling computer while riding outdoors and also take advantage of training apps such as Zwift, TrainerRoad or The Sufferfest on the turbo trainer, consider a dual-band sensor. With a dual-band heart-rate monitor, you can connect seamlessly to your ANT+ enabled computer and laptop, phone or tablet without needing an ANT+ dongle or a second sensor.
Another consideration to make is that most Bluetooth devices can only communicate with one other device at a time, while ANT+ can broadcast to an unlimited amount. If you're one to ride on Zwift but record the ride on your head unit or watch, it's something to keep in mind.
Are you a triathlete or do you incorporate running or swimming into your training? Some heart-rate sensors offer running metrics such as vertical oscillation and cadence, while others are waterproof and can be worn in the pool and only record some data.
If you're looking for a strap, it may also require a tiny bit of maintenance. Usually, the sensor clips onto the strap with a pair of metal straps which will be exposed to quite a lot of sweat over their lifecycle and, these do occasionally succumb to corrosion. You can prolong the life of your HR strap with regular washing (some are machine washable while others aren't, refer to the tag for instructions) and a small dab of dielectric grease can help if you're an extremely salty person.