Heart Rate to Burn Fat and Calories

For many people, working out is about burning fat and calories to lose weight and tone muscles. An effective workout, especially if weight loss is your goal, should increase your heart rate to your target heart rate zone so that you burn fat and calories efficiently.

Your target heart rate zone is the range of beats per minute to strive for during exercise. To find your target heart rate zone, first determine your maximum heart rate, estimated as 220 minus your age. Brigham and Women's Hospital recommends a target heart rate zone between 50 and 75 percent of your maximum heart rate. For example, a 20-year-old would have an approximate maximum heart rate of 200 beats per minute and a target zone of 100 to 150 beats per minute.

Discovery Health strongly cautions against exceeding your maximum heart rate during exercise. This number is the upper limit of what your body can handle during vigorous physical activity, increasing the risk of strain or injury, and exceeding the target zone provides little additional benefit. Aim for the target heart rate zone to work out efficiently.

In the late 80s and early 90s, the idea of the "fat-burning zone" took off. The idea was that a lower-intensity workout, one that maintained the heart rate at around 50 percent of the maximum heart rate, was the most efficient way to burn fat. This is because exercise at a lower intensity encourages the body to use fat rather than carbohydrates as a source of fuel, so a higher percentage of the calories burned during this type of workout come from fat. Naturally, many people assumed that exercising within the fat-burning zone was the best way to lose body fat.

According to Prevention Magazine, this assumption was a false one. In the intervening years, the idea of the fat-burning zone has been debunked time and again. While lower-intensity exercise does encourage the body to burn fat, exercising at a higher intensity of around 70 percent of the maximum heart rate is more effective overall. High-intensity exercise burns just as much fat and significantly more calories than lower-intensity exercises. No matter what the body uses to fuel the workout, burning more calories is the most effective way to lose weight and body fat.

You have several options when it comes to monitoring your heart rate as you exercise. It all depends on how much you want to invest in your workout and how much time you want to take to monitor your heart rate.

The simplest and cheapest option is to check your pulse manually during the course of your workout. Stop and take your pulse during a rest period. Brigham and Women's advises doing so within the first five seconds of rest, before your heart rate begins to drop back down. Hold two fingers against your wrist, count your heartbeats for 10 seconds, and multiply that number by six to find the number of beats per minute.

Have a gym membership? Many cardio machines at the gym are equipped with heart rate monitors as well as pre-programmed workouts designed to raise your heart rate to your target zone based on your age and other factors.

If you can afford to invest more into your workout, consider buying a heart rate monitor to calculate your heart rate automatically. No gym membership is required, and a monitor will be more accurate than a manual reading.

The two main types of heart rate monitors are chest-strap models and finger-sensor models. According to REI, chest-strap models tend to be more accurate than finger-sensor models, but they're also more expensive.

Finger sensor models require you to touch a sensor on the monitor to read your heart rate. These models are simpler, more comfortable, and less expensive than a chest strap, but they are less accurate (at about 95 percent accuracy, according to REI), and they require you to pause during exercise to measure your heart rate.

Any high-intensity cardiovascular exercise that elevates your heart rate to the higher end of your target heart rate zone will help you burn fat and lose weight. Monitoring your heart rate during cardiovascular activity such as running or biking is one way to form an effective workout program.

If you prefer a more structured regimen, plenty of trainers and experts have designed workouts to help you reach your target zone. Fitness magazines such as Men's Health, Women's Health, Prevention, and many others offer specific workouts designed for fat loss. Typically these include a combination of cardio and strength training in a fast-paced interval or circuit-training program to get your heart pumping.

Whatever exercise program you follow, the key is in the numbers. Your heart rate must stay in the target zone, close to 70 percent of your maximum heart rate, to see the fastest results.