It can sometimes be difficult to judge the right pace to be running at. Are you doing that long run too fast? Should you be doing that tempo run a little faster, pushing a little harder? It's difficult sometimes to get an answer to these type of questions.

A good way to answer these questions is with hear rate training. Based on your maximum heart rate, you can work out particular 'zones' for your heart rate. You can then use that information with confidence knowing that long runs should be done in the aerobic zone, and tempo runs should be done in the threshold zone.

I find the best way to determine your maximum heart rate is to simply run. Next time you complete any kind of interval session, take your heart rate monitor with you. It should be able to give you your maximum heart rate for the session. You can be confident that this will be very close to your maximum heart rate. If the session is a longer, you may not quite hit it. With a shorter, harder session, you will get close to it.

A rough estimate of your heart rate is given by this formula,

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Maximum heart rate varies from indivdual to individual, and is more dependant on genetics than it is on general fitness. This formula will give you a good starting point, but really the best way to do is through experimentation.

The first zone is the 'red line' zone. From the range 90%-100%, you can see you are going to be very close to your maximum hear rate. This zone should only be used for high intensity interval training. In other words, you're not going to be able to stay in this zone for very long at all.

As an example, if your maximum heart rate is 190, this zone is going to be from 171 beats per minute to 190 beats per minute (bpm). Even 171 is still close to your maximum heart rate, so you're not going to be able to sustain this for long.

This second zone is the threshold zone. It's a little bit easier than the red line zone, but your heart rate is still fairly high. You should use this zone for your tempo runs, and for 10k races. It will be hard, but by training in this zone you can improve your VO2max. In simpler terms, you will improve your body's ability to effectively use Oxygen.

Again, if your maximum heart rate is 190, this zone is going to be 152-171. This is a little bit down from your maximum heart rate, but not a huge amount.

This third zone is the aerobic zone. This is a much easier zone than the red line zone and the threshold zone, you should be able to sustain it for much longer. This is where you need to be for all your long runs.

This is also the zone you need to be in for a half-marathon, but you need to be at the upper end of this of this zone. Be very careful you don't stray in to zone 2 for too long, as you will pay for it later in the race. If you've done the training you should be able to do a marathon in this zone as well, but towards the lower end of the zone.

Continuing our example, based on a maximum heart rate of 190, this zone is going to be 133-152. This is a much easier zone to be running in. If only we could complete all our runs in this zone!

There are other benefits of training and even living from time to time with a heart rate monitor. The other important figure for your heart rate you need to find is your resting heart rate. When you wake up in the morning, put on your heart rate monitor, and find your average heart rate for a minute. This is your resting heart rate.

Your resting heart is determined by general fitness, genetics, and age. By looking to see how your resting heart rate changes from day to day can tell you what state your body is.

If your body is still recovering from a hard training sessions, you will see your resting heart rate a little elevated. Is it wise to be doing another hard training session when your body is still recovering from the previous one? I doubt it.

You will also see an increase in your resting heart rate with illness. An elevated resting heart rate can sometimes warn of you an impending cold. Also, it can also tell you when your immune system has recovered from that kind of infection.