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Categories > Exercise and Fitness > Cardio/aerobic exercise

Is your workout working?

If the sweat pouring off you is any indication, you’re getting a good workout. But how do you know for sure that you’re getting the most out of your routine—or if you’re overdoing it? That’s where a heart rate monitor can help.

A heart rate monitor gauges your exercise intensity by measuring how fast your heart beats during activity. It consists of a transmitter, which is worn against your chest, and a wristwatch, which receives information about your heart rate from the transmitter. Monitors may have extra features such as calories burned and target training zone. You can get one for as little as $40, or you can spend more than $100.

Getting the most out of your monitor

To effectively use a heart rate monitor, you first need to figure out your maximum heart rate, which is based on age (your heart rate slows down as you get older). Don’t overdo it, as exercising above your maximum won’t provide any additional benefit and could increase your risk for injury. To find your maximum heart rate, subtract your age from 220 (your monitor may calculate this for you).

Next, you need to know your target training zone to help you find the right intensity. Again, your monitor may do this for you. The zone is expressed as a range based on a percentage of your maximum heart rate:

  • 60-70 percent = low-intensity exercise (leisurely walking)
  • 70-80 percen t = medium-intensity exercise (dancing)
  • 80 percent and higher = high-intensity exercise (playing singles tennis)

For example, if you’re 50 years old, your maximum heart rate is 170 (220-50). In order to get a high-intensity workout, you’ll need to keep your heart rate at 136 beats per minute or higher (170 x .8).

If you’ve had a heart attack or have a health condition like diabetes or heart disease, or if you take medications such as beta blockers, consult with your healthcare provider before starting any exercise program. He or she will likely want you to undergo testing to determine a safe level of exercise for you, and may recommend cardiac rehabilitation, which includes supervised exercise.