Maximum Heart Rate
Heart rate (HR) is the number of times your heart beats in one minute, measured in beats per minute (bpm). Maximum heart rate (MHR) is the highest number of beats your body can reach when exercising at full effort.
Everyone’s MHR is different, and it varies depending on several factors such as:
- A person’s age — as you get older, your MHR gradually decreases.
- Fitness level — trained athletes usually have a lower resting heart rate.
- Training Level
- Body Weight
- Nutrition
- Fatigue on test day
- Calculation method — some devices and sensors are more accurate than others.
- Type of test performed
An athlete’s maximum heart rate will usually be higher, while a less trained person’s will be lower. On top of that, someone who is not very active will often struggle to even reach their true MHR.
Note: Heart rate changes over time and usually rises during periods of inactivity. The same person will not have the same resting HR if they’re training several times a week versus if they stop all activity.
Calculate your MHR
Heart rate can be seen as a direct reflection of the effort you’re putting in.
There are different tests you can use to calculate your maximum heart rate, similar to those used for… calculating your MAS. Here are two tests you can try below.
Warning: during a maximum effort test, the goal is to push yourself all the way—without putting yourself in danger. Make sure you’re healthy, have at least a basic level of fitness to do the test, and ideally, don’t do it alone.
Swimming MHR Field Test
The idea is to measure your heart rate right after a long effort.
Step 1: start with at least 20 minutes of warm-up in the water.
Step 2: swim 200 to 400 m depending on your level (200 m for recreational swimmers, 400 m for competitive swimmers), picking up the pace every 50 m and finishing the last 50 m all-out. Your heart rate at the finish is your MHR.
Half-Cooper test
The Half-Cooper test is a very effective way to calculate your MAS, and it works the same way for determining your maximum heart rate. (Check out our article on MAS for the full details of the test) The heart rate you reach at the end of an all-out effort is considered your MHR, expressed in beats per minute (bpm).
So, at the end of the Half-Cooper test, the heart rate you see on your watch is your MHR. If you don’t have a watch, you can measure it by taking your pulse.
Knowing Your Heart Rate
At Rest
- Take your pulse: place two fingers under your jaw to feel your artery. Count the beats for 10 seconds, then multiply by 6. That gives you your resting heart rate. Best done in the morning, right after waking up.
- Get a medical check-up: very common — doctors regularly measure heart rate to make sure your heart is working properly.
- Wear a fitness watch at night: most smartwatches today track heart rate. Wear yours for 3–4 nights in a row and take the average of the readings during your sleep.
During Exercise
- Take your pulse: do it immediately after stopping, since heart rate drops quickly.
- Read your smartwatch: the wrist sensor will give you a heart rate reading, but measurements in the water are less reliable.
- Use an arm-based heart rate sensor: worn on the biceps, this type of sensor is more accurate than a smartwatch.
- Use a chest-strap heart rate monitor: highly recommended for running, but less reliable in swimming since the strap tends to slip in the water. Still, it can be used if needed.
Why Calculate Your MHR?
Your maximum heart rate is a key reference point — it’s not something you should try to exceed. Knowing your MHR allows you to train hard and push yourself without overworking your heart. The goal is improvement, not risk.
For swimmers aiming to progress, two numbers matter most: MHR and MAS (Maximal Aerobic Speed). These values are closely connected and work together.
Dans de nombreux entraînements, l'intensité est exprimée en % de fréquence cardiaque et la vitesse en % de VMA. Ainsi, se connaitre permet au nageur de suivre un entrainement précis, de calculer ses intensités et allures, selon les objectifs et le travail recherché.
This article is designed to simplify and explain — it’s not a scientific paper. It covers general, basic cases and is not meant to provide individualized prescriptions. Remember: variations between people are influenced by many factors, so some details may not apply to you personally.