Heart Rate Monitors and Heart Rate Training
By Kelly Olsen
Heart Rate Monitors (HRMs) have been around for a while, but it is relatively recently that the training techniques and thinking have dovetailed with the technology. This now means that experts advocate training within your heart rate zones as the best way to get the most out of your time spent training. It is important not to be put off by the thought that you need to measure your heart rate as it is relatively straightforward and applies as much to someone who has started walking to improve their general fitness or lose weight right up to those who are training for a longer-term goal such as a triathlon or a marathon. Heart Rate Monitors are not just for ‘serious’ athletes and runners - they are a simple and effective way to ensure that you are either maximizing your exercise to lose weight, build your endurance or fitness.
I recently wrote an article on walking and certainly the best way to ensure that your walking regime gives you the most benefit is to use a heart rate monitor. Certainly I have managed to increase my fitness levels and weight loss by knowing which heart rate zone I am exercising within.
Why Use a Heart Rate Monitor?
An HRM is a device that you wear during any kind of exercise and is there to accurately record your heart rate. This gives you immediate feedback about your ‘work rate’ which is a measure of how hard your heart is working.
The fitness of your heart is the key to aerobic fitness, which is exactly what you want if you are trying to lose or maintain weight or build your general fitness levels. According to the advice on the London Marathon Guide using a Heart Rate Monitor is one of the most effective aids for tracking and developing your progress on the path to increased aerobic endurance. If you are definitely not up for the Marathon then the Rambler’s Association and the Nordic Walking Association also recommend the use of an HRM to track progress.
Makes Monitoring Easy
Stopping to take your pulse during a workout is not exactly ideal. Not only will your heart rate reduce as you’ve stopped, it is not a complete and accurate measure, HRMs constantly measure your heart rate through the whole workout. Most HRMs have both a graphical display, audible alerts and are programmable to suit your goals.
Measure to Manage
Ensuring that your heart rate stays within a given zone for your age and fitness goals will significantly increase the benefits of your activity. It is also motivating as you will be able to see improvements in your heart rate as it should reduce as you get fitter. You could use other methods such as ‘How out of breath am I?’ or ‘How tired am I?’ but these are very subjective measures. Using an HRM will ensure that you work as hard as you need to and stay there and prevent so-called under training – so no slacking!
Most HRMs show you the number of calories burned during your workout. Actually seeing the amount calories burned and progress in your overall fitness is really motivating. It also means that if you are trying to lose weight and you are keeping a food and exercise diary, accurately measuring the number of calories expended through exercise is essential. Whilst we are on that subject, all the experts say that safe, maintainable weight loss is more likely to be achieved when you keep a food diary and increase your activity levels.
It Ain’t Rocket Science…
Using an HRM does not require a degree in mechanical engineering, but is does require you to add some details, such as age. Often there are other excellent functions, such as the features on the Polar range. Polar’s OwnZone™ determines your specific heart rates limits for a given session and Polar’s OwnIndex™ which is a 5 minute fitness test to measure where you are right now. It is worth understanding that you do need to record some details so that your optimum heart rate training zone is accurate, the good thing is that you do not have to program in your work-rate zones for the heart, although you can tailor it, remember that an HRM will work it out for you. As usual with all gadgets there’s the simple functionality that you can use to get started then there are extended features for those of us who love to play!
So, if you do want to know a bit more about the science behind it here’s the details…
You need to know two numbers, your maximum heart rate (MHR) – the fastest rate your heart is able to beat per minute and your resting heart rate (RHR) – the rate at which your heart beats when you are completely inactive and have no external stimuli such as music, stress or general background noise. From these you can accurately calculate your training zones.
Establishing Maximum Heart Rate (MHR)
There are several ways to do this based on age as follows:
If you have been fairly sedentary up until now subtract your current age from 226 for women and 220 for men – this is your MHR.
For example a 36 year old man’s MHR would be 220 – 35 = 185 beats per minute.
If you are already fairly active and whether you are a man or woman subtract your age from 205.
For example, a 35 year old man or woman’s MHR would be 205 – 35 = 170 beats per minute.
If you are very active then you may wish to use the percentage formula where as a man you subtract 80% of your age from 214 and a woman should subtract 70% of their age from 209. For example, a 35 year woman’s MHR would be 35 x 0.7 = 24.5 then 209 – 24.5 = 184.5 beats per minute.
These formulas are based on the standard curves and they represent the ‘normal’ MHRs for a specific age, they are pretty close to your own MHR
Want to Be Exact in Your Heart Rate Measurement?
Measure Your MHR
The only way to do this is to do a ‘fitness test’ where you exert yourself for several minutes, whilst wearing your HRM watch and strap. Most good HRMs have a fitness test option. You could of course ‘do it yourself’ and the recommended way is to undergo some interval training. That is where you exert yourself vigorously for a given distance or time and then take it a bit easier for a specific distance or time.
Two ways you can do this are:
Sprint, preferably up a hill for 300 – 500m metres, and then jog back down. If you do this several times – say 5 or 6 you are very likely to reach your maximum heart rate. This figure can then be used to program manually into your Heart Rate Monitor Watch.
Gym or Machine Test
Use a treadmill and do basically the same as above, choose a distance or time to really sprint and then the same amount of time or distance to jog, wearing your HRM of course!
Measure Your RHR
Fit individuals have low resting heart rates and as you get fitter yours should decrease. If you are very sedentary and unfit your RHR could be 90 beats per minute (bpm) or above, whereas a fit individual could be around the 60 bpm mark. Why is this? Each heartbeat of an athletic person such as an elite runner pumps more than twice as much blood as that of someone who does not undergo much activity. This means that the heart beats less whilst still providing enough oxygen/blood flow to the body. This kind of strong and large heart is indicative of a high level of aerobic fitness.
Actually measuring your RHR is quite difficult and the best time to do it is before you get out of bed. You are less likely to be stressed nor have you had your injection of caffeine! Lay still and calm for 2 or 3 minutes and let the HRM record your heart rate.
Calculating Your Training Zones
If you have used the HRM in automatic setting then your heart rate zones will be calculated for you. This is important as training without knowing what you heart rate zones are eliminates all the benefits of using a heart rate monitor. Again, it is the most accurate way to measure calories burned and for people who are following a weight loss or weight maintenance plan this is very important.
Here’s a guide to the training zones…
60% to 70% of your MHR (or energy efficient for weight loss). If you are exercising in this zone you are mostly burning fat. A mistake that lots of people make when their goal is weight loss is to go hell for leather when they are training - more pain does not necessarily mean more gain. In addition, this recovery zone allows your body to regain glycogen which you may have expended doing a faster paced workout.
Aerobic Zone – 70% to 80% of your MHR
Means literally "with oxygen". Used to describe exercise at an intensity which allows muscles to use oxygen to convert glucose and fat into energy. Aerobic exercise is done at a comfortable pace so that the muscles have sufficient oxygen available.
If you are training in this heart rate zone you are developing your cardiovascular system. Training in this zone will, over a period of time give you fat burning benefits and a greater capacity for aerobic activity, that is you won’t feel so out of breath. Often when spinning this is used and it helps build muscle strength.
Anaerobic Zone – 80% to 90% of Your MHR
Means literally "without oxygen". Usually through high intensity exercise where the muscles lack sufficient oxygen to successfully burn fuel. This results in the body producing lactic acid. Anaerobic exercise is very intense and can only be sustained for short periods of time.
For professional athletes loads of benefit can be gained from this type of exercise, the body uses very little fat and uses glycogen instead BUT what tends to happen is that the body then produces large amounts of lactic acid and usually your heart rate increases but your ability to exercise (your pace) reduces.
Mostly this is used for very short bursts such as a sprint by athletes, for most of us though it probably means you won’t be able to complete your workout.
Maximum Zone – 90% to 100%
Exercising in this zone allows you to develop speed, using spinning as an example, ‘sprinting’ on the bike to 100% of your heart rate for short periods is good for you. Just remember though any exercise done at this level needs to be carefully monitored.
The formula for manually calculating all these zones is: ((MHR-RHR) x Percentage Level) + RHR
For example to train in the middle of the aerobic zone:
If my MHR was 180 and my RHR 70 the calculation would be…
((180 – 70) x 0.75 ) + 70 = 152.5 beats per minute
So when exercising I would aim to keep my heart rate at 152 beats per minute to get the best out of my workout. Remember though it is worth revisiting these and recalculating your zones as you get fitter as your RHR should reduce. If you are using the automatic settings on your HRM, then re-do your fitness test.
Seeing Results and Reaching Your Goals
If you exercise regularly, use an HRM and train within the zone that suits you then you will see good results – ultimately that means a lower heart rate, increased fitness or weight loss. Not only will your heart rate be lower, but you will be able to run, walk, do a step class, jog or cycle the same distance or time but feel as if you are not working so hard – less out of breath, lower heart rate, less sweat! This means, of course, that you need to up your intensity to get to the next level.
Which Heart Rate Monitor Should I Buy?
I think the old adage of buying the best one you can afford is a good rule of thumb. The most popular and accurate are ones that come with a chest strap which contains the heart rate sensor and transmits this to a watch worn on your wrist. Polar have a great range such as the Polar F11 which is intermediate or the Polar F6 or Oregon Scientific Vibra Trainer both of which are good all round HRM watches.
If you are going to buy one, then there should be some basic features as follows…
Ability to measure your heart rate and show it graphically
Should have basic watch functions
Ability to automatically enter data such as your age so your heart rate zones/limits are worked out and used to calculate your exercise intensity and calories burned
Calories burned – some might disagree, but I think this is essential for any HRM purchase.
Some of the more advanced features could be useful, it really depends on what level you intend to go to. Advanced features (which generally come with a higher price tag) include:
Analysis of data collected – giving averages, time spent in different zones
Connectivity to your computer – Polar, for example have the ability for you to upload your training data and track progress
Recording of more than one workout so you can analyse it later.
Accessories to measure distance for runners
A basic heart monitor can cost less than £50 and they go up to a few hundred pounds. Best thing to do is decide on what basic features you must have and use that as a starting point. The good thing is that they are pretty stylish these days and many people wear them as a watch all the time.