Heart Rate Monitors

Heart rate monitors (HRMs) are becoming more and more popular with runners. They’re getting cheaper in price and the technology keeps evolving, but do you need one? Read on to find out more about heart rate monitors and how they can be used as part of your training for the Virgin Money London Marathon.

What do heart rate monitors do?

When you’re doing cardiovascular exercise like running or cycling, it’s your heart rate that determines how hard you’re working and whether the training session is high or low intensity. Heart rate monitors are a simple and effective way to tell you your heart rate, allowing you to monitor your performance and decide whether you need to maintain, ease, or up your pace.

How do they work?

Heart rate monitors usually come in two parts. There’s an elasticated chest strap with sensors that detect your heart rate, and transmit it to a receiver you wear on your wrist. The receiver displays your heart rate in real time and may have other features too, like a stopwatch or calorie counter.

Do I need one?

Heart rate monitors can be a great tool. They can prevent prevent overtraining and give variety to your training programme.

However, they shouldn’t take over as the focus of your workout. Analysing your workouts can be fun but it’s not necessary to monitor every session – using a heart rate monitor shouldn’t start to feel like a chore.

And although heart rate monitors give an accurate indication of how hard you’re working, they shouldn’t be the only method you use to monitor your progress. Remember weather conditions, tiredness and state of mind can all affect your workout.

Which extra features are useful?

Heart rate monitors often have lots of different features and it can be difficult to know what they do and if they’re going to be useful. If you’re thinking of buying a heart rate monitor, we’ve put together a guide to some of the common features below.

Useful features for all runners:

Feature What does it do? How useful is it?
Stopwatch A normal stopwatch to time your workouts is built into the HRM. This often includes a lap timer, clock and calendar too. A stopwatch is an essential bit of kit for most runners, so having one built into your HRM means there’s one less gadget carry around while you’re training.
Backlight A light to illuminate the face of the HRM. This could be an automatic light or one you turn on by pressing a button. A backlight is essential if you want to use your HRM in the dark.
Training zones and alarms You can set limits for the minimum and maximum heart rate you want to maintain during your workout. If your heart rate falls above or below the limits you’ve set, an alarm will go off to let you know. This is useful for keeping an even level of intensity throughout your training session. 
Training zones calculator You can put your details into the HRM, such as your age and weight, and it will automatically calculate your high and low intensity training zones. This is helpful if you’re unsure what your heart rate should be for high or low intensity workouts, or you find the training zones feature difficult to use.
Average or maximum heart rate reading After your workout the HRM tells you the highest heart rate you reached, or gives an average heart rate for the session. Useful to give you a quick overall summary of your performance.

Specialist features which are useful to some runners but not everyone:

Feature What does it do? How useful is it?
Countdown timer You can set the amount of time you want to train for or the target heart rate you want to reach. When you meet your target an alarm will go off to let you know. This is useful if you enjoy mixing high and low intensity exercise in the same workout – for example by doing Fartlek training.
Coded transmission Sometimes other signals being transmitted around you can affect your HRM, giving an inaccurate reading. This feature sends the information from the chest strap to the receiver as a coded message to cut out interference. This is useful if you train in a group or enter races where lots of other runners are using HRMs and signals can get confused. It’s also useful if you train in built-up areas with lots of overhead and underground cables.
PC interface You can download training data from your HRM to your computer. If you keep detailed records of your training to monitor your performance, this is a handy tool to have.
User operated or automatic memory The HRM records your reading when you press a button, or if it’s automatic, stores a reading at set time intervals. This is useful if you enjoy breaking your training sessions down into detail and analysing your performance. However, the user operated memory can often be difficult to use.

Extra features which aren’t always necessary:

Feature What does it do? How useful is it?
Calorie counter The HRM tells you how many calories you’ve burnt during your workout. It can be interesting to know how many calories you’ve burnt but it’s not valuable information - the intensity of your workout should be measured by your heart rate and how you feel.
Fitness tester The HRM rates your level of fitness based on your heart rate readings. Like the calorie counter, this isn’t an essential feature and shouldn’t be relied upon to monitor your progress.
Dual settings Allows two different users to input and store information on the HRM. If you’re the only person using the HRM, this feature isn’t necessary. If you’re not using your HRM to store your training results, more than one person could use the HRM without this feature.