Checklist

If you're thinking about buying a heart-rate monitor, here's what to consider.

Wrist receiver and chest strap

How they work

The models we tested come in two parts: electrodes in a chest strap pick up your heartbeat and send a signal by radio pulse to a wrist receiver which also acts as a watch and stopwatch. The receiver displays your heart rate – heartbeats per minute – while you exercise.

All of the models we tested can be used as a watch or a stopwatch and had programmable heart rate zones and zone alarms. Some can record laps and display the calories you burn (and other data) for post-exercise analysis.

If you’re exercising to maintain general fitness rather than to compete, you’re unlikely to use many of the features offered by the more expensive monitors. And even though a monitor can be an excellent way to judge the intensity of your workout, it’s still important to pay attention to how your body feels. You shouldn’t rely on a heart rate monitor to judge the state of your health.
 

Features to consider

• Maximum heart rate allows you to set boundaries in training. Most monitors can calculate your maximum heart rate from information about your body (such as age, sex, weight, height). For a rough estimate try this formula: 220 minus your age (for a 40-year-old that would be 220 - 40 = 180 beats per minute).
  
  To get the best from your exercise, aim to work within boundaries based on your maximum heart rate. A good target zone is between 85 percent and 60 percent of your maximum. Around 85 percent is high intensity; 60 to 75 percent is a moderate workout.
• Programmable heart-rate zone means you can enter information to calculate your target training zone.
• Zone alarm lets you know when your heart rate is outside your target zone (you’re exercising too intensely or taking it too easy).
• Heart touch lets you display data by bringing the wrist receiver close to the transmitter on the chest belt. It’s useful when gloves make pressing the buttons difficult.
• Recovery mode shows how quickly you recover from a workout (the faster you recover the fitter you are).
• Average heart rate and calories burnt gives you info for post-training analysis – and bragging rights.
• A setting to record laps is essential for sports training.
• Countdown mode can be used for time trials or personal competition-simulations.
• A backlight makes it easier to read the display in low light.
   

Go for comfort

Fancy features aren’t everything. When you’re buying a monitor, focus on the basics:

• a comfortable chest belt that can be easily adjusted to your size
• an easy-to-read screen, with good contrast and large numbers and text.