When we exercise, our muscles start to work harder and require more oxygen and nutrients to function. For this process to happen, blood containing oxygen, fluids and nutrients needs to be pumped around the body. This blood flow will also drain the metabolic waste products away. The heart is the muscles which facilitates this process. When we start to exercise more, the heart starts to pump more blood per stroke, delivering more oxygen to the exercising muscles.
When you run quicker and quicker, your heart rate will increase. Eventually, you will have to stop as your heart will not be able to pump any faster. This number is unique to each individual. It is known as your Maximum Heart Rate, and it will fall over time.
There are physical differences between men and women's hearts. In general, a man's heart is as much as 25% larger than a woman's. A man's heart has the capacity to pump blood easier than a woman's.
When we exercise, it is possible to monitor your heart rate, and then you can train in various heart rate zones. Broadly speaking there are three heart rate zones; Fitness and Weight Control, Endurance and High Performance
•Fitness and Weight Control - This will be between 60 and 70% of your maximum heart rate. Your body will get around 85% of its energy from fat, making it excellent for loosing weight. Just because this is the 'fat burning' zone, doesn't mean it is the most appropriate for loosing weight. When you work out at a higher intensity you will burn more calories overall, and then more fat calories.
•Endurance - This is between 70 and 80% of your maximum heart rate. This level of intensity increases your stamina and cardiovascular fitness.
•High Performance - This is when you push your body above 80% of your heart rate level. At this level, your level of effort begins to outpace your body's ability to absorb oxygen. This is a level appropriate for further approving stamina and cardiovascular fitness.
It is possible to get these zones down narrowed down even more, using ideas such as Threshold, 10K and even 5K effort intensity.
If you were to run at a constant speed a few times a week, and monitor your heart rate, it will start to drop over time. You are becoming more efficient at running at that speed, you are becoming fitter. The fitness of the heart and overall cardiovascular health is the single most important factor in developing your potential as a runner. Due to this fact, you would think that more runners would invest in a heart rate monitor, but also use it correctly, and this rarely happens.
Why would you train using heart rate?
Lets follow our hypothetical runner George. George wants to run a 4 hour marathon. This would be 9 minutes 10 seconds a mile for the duration of a marathon. So, using pace formulas, roughly speaking, George's Long Run would be at 10minutes a mile and his threshold pace around 8minutes 15 seconds a mile. Each session George runs for the next 16 weeks will be run at roughly these set paces or a bit faster as George gets fitter. Come rain or shine, George will run at those paces and then run a four hour marathon. It is as simple as that.
There is one huge flaw with George's plan. His pace and performance on any given day will be affected by so many factors, some within and some out of his control. Here are a few; terrain, hills, hydration levels, sleep, weather, altitude, energy levels and fatigue from training. All of these factors and other can affect your pace, and if George is particularly unlucky all those factors will affect him at the same time.
Just taking hills as an example, running downhill is a lot easier than going uphill. On a 4 mile run, George wants to run at his 'marathon pace'; however the loop he is running has a 2 mile hill in it. To maintain the 9 minutes 10 seconds a mile, George will have to work a lot harder going up the hill than he will on the flat ground. The run should be an easy run, however because of the hill George will be running at a much harder intensity that he needs to. If this process keeps continuing over the training, George will be running much harder than he needs to during various sessions, he will get fatigued and most probably won't run his four hour marathon.
I am not saying that running at a set pace is a waste of time at all, it is important, especially when you get to the sharper end of races, but the intensity of your training workouts is much more important.
Setting a designated Heart Rate value, or Heart Rate band for each session allows for a coach and you to control the session a lot more than pace does, it gives the session a lot more purpose and you will then begin to train at appropriate levels and become a better athlete.
Even if you pace is down on a given session, your intensity will be correct for what you are trying to achieve. For example, during a threshold session, you want to be getting close to your lactate threshold but not crossing it. By training to a specific heart rate value, you can do that every session and not work too hard on any give day trying to crack a pace which just isn't coming for one of many reasons.
What Heart Rate?
I have stressed the importance of running at a give heart rate, but now you need to know what levels to actually run at.
At Full Potential, we use the following Heart Rate zones:
•Easy Run 60 - 70%
•Long Run - 65 - 75%
•Marathon Pace - 78%
•Threshold/Kenyan Hills - 80 - 85%
•10k Pace - 90%
•5k and above - 95%
The above levels are all percentages of maximum heart rate, so in order to correctly work out your zones, you need accurate maximum heart rate details. This is where so many people fail. They spend a lot of money on these expensive bits of kit and use them completely incorrectly.
Ask almost anyone how to get your maximum heart rate and they will likely tell you that you use the simple formula of 220 - age, or something similar. Once you have this value, you have your heart rate zones. However, life really is NOT that simple!
A paper by Robert A. Robergs and Roberto Landwehr in the Official Journal of The American Society if Exercise Physiologists from May 2002, conclude that 220 - Age - "has no scientific merit for use in exercise physiology and related fields". That is fairly conclusive stuff.
If you look at the graph below, it provides maximum heart rate information for a number of participants in a study, and the blue line is the line of 220 - age. There is no way that the blue line is the line of best fit, and if by some miracle it is, the use of best has become very liberal. The real conclusion from that data is that your maximum heart rate is a very personal piece of data, and if you were to use 220 - age to calculate your maximum heart rate, you would most likely be training at the wrong level.
Hopefully the thought of using 220 - age to calculate your max heart rate has been completely dismissed from your mind, the question then becomes how to work out your maximum heart rate.
There are a few options;
The least expensive and most effective way is to do interval training, either on a slight hill over approximately 200 metres, or around a track. Sprint the distance as fast as you can, take a 20 - 30 seconds to recover and repeat this 5 times. This process should allow you to get as close as possible to your maximum heart rate. To do this test, you will need a heart rate monitor!
Going to a Laboratory, you carry out a test which involves you exercising on a fixed device (such as a treadmill, or bike) and your heart rate is monitored by a professional. These tests may also involve blood being taken to determine blood lactate levels. These test can be quite expensive, coming in around £150 - £200 but will provide you with the most accurate information.
For more information on Laboratory Tests and booking one, check out our Lactate Threshold Testing article.
Heart Rate history
Once you have done enough running, you may want to record your heart rate at various training intensities over a few weeks. By recording your heart rates and taking averages at various levels, you can build up a history of your correct heart rate zones. We are currently working with Full Potential on a process, because it can cause a few problems if not done correctly!
How to measure Heart Rate
To measure your heart rate, you can do this either with a heart rate monitor, which will be soft strap, worn around your chest with electrodes to take your heart rate, and the strap will wirelessly communicate to a watch to give you heart rate data. There are watches which read your heart rate on your wrist, but this can be a little bit less accurate, and require a bulky watch. The other way to measure your heart rate is manually count beats per minute over a set period of time. This method is close to impossible whilst you are running but can be used when you have stopped running.
To see what a heart rate monitor looks like, take a look at our Watches section to see reviews on a number of timepieces which include heart rate monitors. With some of these watches, you can set up your zones, and the watch will start to beep at you if you are running too fast or too slow during a given session.
Resting Herat Rate
A lot of runners will monitor their resting heart rate, usually in the morning when they wake up. It is a strong predictor of cardiovascular health and fitness levels.
Depending on how you wake up will depend on when you should take your heart rate. If you have a loud alarm which really startles you in the morning, then wait a few minutes before taking your resting heart rate, otherwise it will be rather high! If you have naturally woken up, you are good to take it almost immediately. What is important is to take it the same way each day.
So, after a few minutes of sitting quietly, monitor your heart rate. Either count the beats over a 60 second period, or count them over 10 seconds and multiply that number by 6. Take your resting heart rate over a few days to get a good average.
One great feature of monitoring resting heart rate is that you can see if you are over training, or possibly coming down with a cold. For example, your heart rate may be one or two beats high, and you feel a bit of a tickle in your throat. This is a sign that something is possibly coming on and you can back off your training a little bit. On the same token, if your heart rate is abnormally low, that can be a sign of fatigue.
Your resting heart rate should decrease over time, as you get fitter.
Recovery Heart Rate
Recovery Heart Rate is your heart's ability to return to a normal rate after an activity within a specific amount of time. In general, a faster heart rate recovery from an activity is an indication of an improved fitness level. Some Garmin running devices (610 and 910XT), and the Timex Run Trainer, will automatically work this out using features inbuilt into the watch.
To race or not to race
Personally, I do not race with a heart rate monitor on. I expect my heart rate to be a bit high on race day and I think that it would stress me out to know what it is at. It is also important to learn to race to how your body is feeling. However, as a beginner there is certainly an argument to be had to wear it for a few times, to get to know your heart rate a bit better and see actually how high you can get your heart rate!
As you get fitter, you can start to monitor your pace at various heart rate levels and you should start to see your heart rate start to drop at paces you used to run. You start to become more efficient at running at a steady pace.
Hopefully this has given you an introduction into heart rate, why it is excellent to train using heart rate and also why 220 - age is not a good indicator of your maximum heart rate.
Get these areas right, and you will be training like some of the best athletes around and will make huge gains over your friends and running colleagues.