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How do I calculate my Maximum Heart Rate (MHR)?


Heart Rate: what you need to know

Heart Rate (HR): the number of times your heart beats in 1 minute

HRmax (maximum) is the maximum number of times your heart can beat in 1 minute

- HRmax is not greatly impacted by training

- HRmax decreases progressively with age (we lose about 1 beat per year)

Resting HR changes based upon your physical condition: the more fit you are, the lower your resting HR

Heart rate monitors are made of a transmitter attached to a belt around your chest and a receiver around your wrist. The heart rate monitor is for your body what the rev counter is for your car. Runners' heart rate monitors measure the number of heartbeats at each moment and allow them to avoid over-training.


How do I determine my HRmax?

There are two solutions:

1/ Either the Astrand method, which involves applying the following formula:

For women: 226-your age; (Example for a 40-year-old woman; 226-40 = 186 bpm)

For men: 220-your age; (Example for a 40-year-old man; 220-40 = 180 bpm)

This is a simple method that you can apply immediately, but which remains theoretical and based upon averages, and therefore is unreliable for a part of the population (which you may belong to).

2/ Or you perform a field test; there, you are certain to have YOUR HRmax.

To do so, after a twenty-minute warm-up, you speed up until you reach your maximum output (you have to really "give it your all") over 1000m or 4 minutes, and by intervals of 100m or 30 seconds. Once you are there, you read the number displayed on your heart rate monitor, and there you'll have YOUR HRmax.


How do I determine the % of my HR to use?

Here again, there are 2 techniques:

1/ The easiest is to apply the desired % directly to your HRmax. For example: HRmax 185x85%=157 bpm, so when you want to train at 85%, you will work in the zone around 157 (between 155 and 159). Once you have determined your HRmax, you will be able to work within HR zones.

At around 70% HR, but not exceeding 75%, this will be your endurance training zone (jogging)

Between 85 and 90% will be your anaerobic threshold (pace you are able to sustain for around 1 hour)

Between 95 and 100% will be your Maximum Aerobic Capacity zone (VO2 max)

Of course, these are work zones, and you shouldn't spend the whole time staring at your heart rate monitor. You should simply check it from time to time in order to keep from straying into another zone (with a bit of practice, without even looking at your monitor, you will know where you are).

2/ The highest performing

Now here is another way which is much more "pro", is more grounded in reality, and performs better for optimising your potential, which is what everyone wants.

To do this, you need to know both your HRmax, and also your resting HR - that is to say, the heart rate you should take when waking up in the morning (it is this number which should improve with good training). You should take this measurement once a week if possible, and especially under the same conditions.

Once you know your HRmax and your resting HR, by SUBTRACTING the two, you will get what is called the heart rate reserve. This is the number you should use when applying the % heart rate that you would like.


To understand this, here are some examples:

For runner No.1, HRmax=185; resting HR=68, the HR reserve will be 185-68=117

Then, if you would like to train your endurance at 70%, you will do: 117 x 70/100 = 82

To this number, you add your resting HR: 82+68 = 150 bpm, so for endurance, you should run at around 150 bpm.

For runner No.2, HRmax=185; resting HR 50, the HR reserve will be 185-50=135. If you still want to train at 70%, this will be 135 x 70/100= 94.

To this number, you add your resting HR 94+50 = 144 bpm, so you should run at around 144 bpm.

These two examples show the importance of accounting for your HR reserve, since by applying the same % to our 2 individuals, who have an identical HR max, and who wish to make an equal effort, they will not train at the same heart rate range.


This second method of calculation is certainly a bit more limiting, but aren't you capable of taking that step to optimise your training?