Maximum Heart Rate, HRmax
Heart rate is the measurement of the work your heart does. Heart rate can be expressed as the number of beats per minute or as percentage of your maximum heart rate. Heart rate can also be expressed as a percentage of your heart rate reserve, meaning the difference between your resting heart rate and maximum heart rate (HRR = HRmax - HRrest). In Polar software or during strength training, heart rate can be displayed as a graphical trend. (HRmax) is the highest number of beats per minute (bpm) your heart can reach during maximum physical exertion. It is individual and depends on hereditary factors and your age.
If you wish to reliably measure the intensity of your training, it's important to know how hard your heart can work when it's pumping at its maximum capacity. The more accurately you know your HRmax the more accurately you can define the heart rate limits or sport zones you need to use to get the optimal training benefit. If you overestimate your HRmax, the heart rate limits within which you train will be higher than they should be. If you underestimate your HRmax, then you will be training at too low intensities.
Most Polar models allow direct entry of a HRmax value. If you don't know your HRmax, most models use the age-based formula (220 - age = HRmax).
It’s important to differentiate between measuring HRmax and estimating HRmax.
1. Laboratory test
Measuring heart rate during maximal physical effort in a laboratory test is the most reliable and accurate way to determine HRmax. The test is usually done by running on a treadmill or taking a bicycle test and it’s supervised, often by a cardiologist or exercise physiologist.
2. Field test
You can do a field test together with a training partner. If you have some hard training under your belt from recent weeks, and know that you can hit a high HR without unusual discomfort, you can determine the HRmax yourself. Use your training computer to see how high a heart rate you can reach. If you see your heart rate go above the value suggested by the age formula, take this value as your HRmax. If later you go above it, update the HRmax value.
Note! For safety reasons we recommend you do the test with someone else present, be it a friend or your personal trainer. If you are unsure, consult your physician before undertaking the test.
Field test example
1. Warm up for 15 minutes on a flat surface. Build up to your usual training pace.
2. Choose e.g. a hill that will take more than 2 minutes to climb. Run up the hill/steps once building to as hard a pace as you can hold for 20 minutes.. Return to the base of the hill.
3. Run up the hill again. Get your heart going as hard as you can to be able to just about hold it there for 3 kilometers. Observe your highest heart rate on the display.
Note! Your HRmax is approximately 10 beats higher than the now-noted value.
4. Run back down the hill. Allow your heart rate to drop 30-40 beats per minute from where it was.
5. Run up the hill once again at a pace that you can only hold for 1 minute. Try to run halfway up the hills. Observe your highest heart rate. This brings you close to your maximum heart rate. You can use this value as your HRmax to set sport zones.
6. Make sure you cool-down for a minimum of 10 minutes.
You can use different methods to estimate your true HRmax:
1. Age-based formulas
Age is often used as a predictive variable to estimate HRmax. It has been observed to be one single variable to most clearly affect HRmax value. It is also a variable that is easily available. Most formulas used to estimate HRmax have been deduced by comparing individual HRmax values in different age groups, so too the age-based (220 - age = HRmax) formula. In most cases formulas give a sufficient accuracy for determining training intensity.
Most Polar models have the age-based formula available in case you do not know your HRmax. If yours doesn’t have it, you can estimate it yourself: 220 – your age = HRmax. Even with a margin of error, always related to estimations, the formula allows applicable determination of exercise intensity. You can update your HRmax value in every Polar product if you decide to get your HRmax measured or notice that you can go above the age estimate.
If your HRmax has not been reliably tested and if your Polar training computer has the HRmax-p (predicted HRmax) feature, you can do Polar Fitness Test and use the given HRmax-p score as your HRmax estimation. See your product manual to know if your training computer has this feature.
Your HRmax is highly individual. It’s largely determined by genetic factors.
Both cross-sectional and longitudinal studies show that age affects HRmax, the premise being that with age your HRmax goes down. Most formulas used to estimate HRmax have been deduced by comparing individual HRmax values in different age groups.
Endurance training may reduce your HRmax to a degree. More often than not, however, it has no impact on your true HRmax value.