Heart rate (HR) remains one of the most used metrics in the sports community to measure intensity. It is a relevant tool to use and monitor for multiple purposes, from clinical assessments to sports performance. While there are two main ways to measure HR during exercise, they each present their pros and cons in practical settings. Now with our new COROS Heart Rate Monitor, we have taken the best of both worlds to create a reliable and comfortable tool to assist you in your training journey.

Keep reading for a breakdown of this metric from a coaching perspective.


How to Measure Heart Rate During Exercise?

Wearables now come with two different HR sensors that can be worn in various places on your body- Optical and ECG. Let's differentiate both below through their own pros and cons.

Sensors (main area)How do they measure HR?ProsCons
Optical (wrist)Measures the pace of blood flow through lightIncreased comfort
Easily accessible
Affected by more potential variables
Increased delay for blood flow to adjust from heart to wrist
ECG (chest)Measures the electric signals of the heartGold standard accuracy
Increased responsiveness to changes in HR
Less comfortable
The higher the heart rate, the harder your body has to work to function. However, many variables influence this process (such as fatigue, temperature, altitude, and others), which is why your HR may look out of the ordinary sometimes.


Where Does the New COROS Heart Rate Monitor Stand?

While the new COROS Heart Rate Monitor uses optical sensors, the area from which they are taking the measurements varies, which is truly where the game-changer comes from. This new tool now has taken the best of both worlds, optical and ECG sensors, by keeping their strengths and therefore attenuating their weaknesses.

Our internal testing highlights the HR Monitor being within 3bpm of the ECG gold standard for over 95% of the time during running activities.

Let's dig deeper in some of the best qualities the new COROS Heart Rate Monitor has to offer.

COROS Heart Rate Monitor is very practical during climbing sessions.


Shorter Delay in HR During High-Intensity Exercise

Heart rate is a reflection of how much your body is working at any given moment. However, the body has to follow a strict chain of reactions before you can actually see a difference in your heart rate. If you suddenly start a 400m sprint, your muscles will send a signal to your brain requiring more oxygen, which will then send a signal back to the heart to increase pumping and bring hemoglobin (transporter of oxygen) to the working muscles. This whole process takes about 20-30sec to notice at the heart level. If you take a measurement at the wrist, far away from the heart, this delay is even longer as you are waiting for the blood flow spike to reach this point.

As the COROS HR Monitor is worn at the biceps (much closer to the heart), it significantly reduces this delay during high-intensity interval sessions more specifically.

Sprint intervals completed (without the HR Monitor), but HR never reaching above the Threshold zone due to the delay from heart to wrist.


No More Cadence Lock

Cadence lock is an unfortunate event that occurs when the optical sensors in the watch capture your cadence instead of your heart rate. This incident is often due to the noise created by external factors (e.g., your cadence) as well as the low blood volume at your wrist. When wearing the COROS HR Monitor around your biceps, you reduce the noise and increase the blood volume, therefore limiting chances of creating cadence lock in your data!

Cadence lock happening from 25 minutes to the end of the run.


You Will Forget You Are Even Wearing It

Although chest straps use a more sophisticated way (ECG) to capture HR, they remain highly uncomfortable to wear regardless of the activity. With the Heart Rate Monitor's soft fabric band, you will forget you are even wearing it and therefore focus on what is truly important- your training.

COROS Heart Rate Monitor worn on the biceps during cycling activities.


TIME Best Inventions of 2023

COROS Heart Rate Monitor has been recognized as TIME Best Inventions for 2023. This recognition from TIME highlights COROS’ significant impact on the fitness industry, setting a new standard for precision and user-friendly design and reaffirming the brand’s commitment to innovation and excellence.

Get your own Heart Rate Monitor now and let COROS join you on your journey to explore perfection!


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