What Does Your Heart Rate Need to Be to Burn Fat During Exercise?

Know the right heart rate to burn the most fat.
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Your heart beat is more than just a sign that you're alive. The speed of your heart beat can tell you what type of energy your body is using. During exercise, your body is constantly burning fat; however, the amount you burn depends on how fast your heart is beating.

How to Measure Heart Rate

Your heart rate is simply the speed your heart is beating and it is measured in beats per minute (bpm). When you work out, your heart rate goes up and down to meet the energy demands of your body. To check your heart rate, either place two fingers on your wrist or place two fingers just to the side of your throat and feel for a pulse. Count the heart beats for 10 seconds and then multiply by six to get your bpm. There are also watches and other electronics that can do the work and show your current bpm.

Fat Burning

The simplest way to find your max heart rate is to subtract your age from 220. For example, someone who is 20 years old would have a max heart rate of 200. There are problems with this calculation for those who are in excellent shape because it tends to give too low of a max heart rate. But for most people, this calculation should work fine. If you train at 60 to 70 percent of your heart rate maximum, your body will predominantly burn fat.

The Fat-Burning Zone Dilemma

Your body never burns just one fuel source; it's a changing mixture of carbohydrates and fat. Ultimately, fat loss comes from burning more calories than you consume. Anaerobic training -- training at 80 to 90 percent of max heart rate -- such as sprinting is a better method to burn body fat. Dr. Chris Mohr, registered dietitian and personal trainer, wrote a Bodybuilding.com article and said that although the fat-burning zone burns a greater percentage of calories from fat, you don't burn very many calories overall. He gives an example that walking for 60 minutes at a brisk pace in the fat-burning zone will burn about 300 calories with 60 percent -- or 180 calories -- coming from fat. Interval sprinting for 20 minutes will burn up to 600 calories with 40 percent -- or 240 calories -- coming from fat. For the best bang for your buck, train at higher heart rates to burn the most fat.


Before beginning any new exercise program consult your doctor. Drink water before and during the exercise to prevent dehydration. If your heart rate gets too high, you may feel dizzy; slow down if this happens. Check the running surface for any holes or uneven surfaces so you don't twist an ankle. If you're just beginning, start slowly so you don't strain a muscle. Afterward cool down by stretching your lower body and walking for five minutes. Work with a personal trainer to get an exercise program that's customized for your fitness level.

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