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Heart rate zones can be used to help runners train more effectively. A heart rate zone is simply a range of heart rates. Knowing your zones and working within them will help ensure you're getting the desired training effect.

We identify four main zones that are set according to either a percentage of maximum heart rate or a percentage of heart rate reserve. Running at any heart rate within a zone will, broadly speaking, have a training effect that is similar to running at other heart rates within the same zone.

The Zones

The table below gives a description of the zones and the range of percentages of either maximum heart rate (MHR) or heart rate reserve (HRR) that correspond to each zone.

  MHR Range HRR Range Description
Zone 1/Recovery
65 - 75% 60 - 70%
Zone 1/Recovery
65 - 75% MHR
60 - 70% HRR
This zone is good for general aerobic conditioning and improving endurance. It's sometimes called the "fat burning" zone since you will burn fat most efficiently when running within this range of intensities. Short runs within this zone are perfect for recovery, and it's also ideal for longer runs, warm ups and cool downs.
Zone 2/Aerobic
75 - 85% 70 - 80%
Zone 2/Aerobic
75 - 85% MHR
70 - 80% HRR
This zone is where the majority of the distance runner's training should take place. Training within this zone will improve and strengthen the cardiovascular and peripheral systems, promote increased vascularisation (meaning a greater blood and oxygen supply to muscles), and build resistance to injury.
Zone 3/Anaerobic
85 - 95% 80 - 90%
Zone 3/Anaerobic
85 - 95% MHR
80 - 90% HRR
This zone covers intensities from just below to just above your anaerobic threshold (the middle of this zone is roughly the intensity you could maintain for an hour in a race situation). Training in this zone can help raise your anaerobic threshold meaning you can run harder and faster at both this and other intensities.
Zone 4/Red Line
95 - 100% 90 - 100%
Zone 4/Red Line
95 - 100% MHR
90 - 100% HRR
This is the zone that is used for interval training. Training in this zone will help train your fast twitch muscle fibres and raise your VO2 Max. This type of training should be limited.

Zone 0?

Intensities below 65% MHR or 60% HRR can still be useful, although some coaches would argue they fall into the category of "junk miles". I.e. those miles which are run at a pace too slow to elicit benefits.

Debates about junk miles have raged for ages and despite the extreme view of some coaches, training at low aerobic intensities can still bring about improvements in fitness. It depends on a variety of factors. For example, running at 60% MHR or 55% HRR is better than doing nothing. On the other hand doing all your mileage at this intensity is unlikely to bring about the same improvements as a good mix of training in traditional zones.

We suggest that zone 0 can be a useful alternative to zone 1 if you feel like taking things a little easier.

Using your personal zones

The zone margins have been chosen primarily because they will closely reflect the correct training zones for a majority of runners, but also so that the percentages are conveniently multiples of 5 or 10, which can make the mental arithmetic a little easier if you're out in the field.

Your personal zones are very likely to be a little different from what is listed here. However, since there is overlap in the training effects for each zone, and there is also a wide range to play with, this shouldn't cause too many problems. If you're concerned about hitting the correct intensities then you can concentrate on doing most of your running in the middle of any particular zone. What is probably most beneficial in practice is to run at a wide range of intensities within and across the different zones.

If you plan to make use of heart rate zones then it's really important you have a good idea of your true maximum heart rate. Maximum heart rate calculators can be useful for getting an idea, but individuals will vary wildly, so we strongly recommend performing a proper maximum heart rate test as detailed in our heart rate training guide. Our guide also gives advice on how to determine your resting heart rate.

Many GPS watches and heart rate monitors include a facility that allows you to set your personal heart rate zones and to then monitor your zone during training.

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How It Works

There are two ways to calculate your heart rate training zones.

Maximum Heart Rate

The first method uses your maximum heart rate to determine the zones. You can estimate your maximum heart rate using our calculator, or you can carry out a maximum heart rate test.

Heart Rate Reserve

The second method uses your heart rate reserve to determine the zones.

Heart rate reserve, sometimes known as working heart rate, is simply your maximum heart rate minus your resting heart rate. See our article on training by heart rate for details of how to calculate your resting and maximum heart rates.

The heart rate reserve method is likely to provide slightly more accurate results.

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