Target Heart Rate Calculator
Your target heart rate is a percentage of your maximum heart rate (i.e., the maximum number of times your heart can safely beat per minute during high intensity exercise). Enter your age in our Target Heart Rate Calculator to find your optimum fat burning heart rate (65% of your maximum heart rate). Then add/subtract 5% in both directions to arrive at your fat burning zone.
Your Fat Burning Zone
When you exercise at 60-70% of your maximum heart rate, you’re in the fat burning zone. In this state, your body uses stored body fat, not glucose, as its primary fuel source. More intense exercise (say at 75-85% of your maximum heart rate) burns more calories, but a smaller percentage of those calories comes from fat. Nonetheless, since you’re burning more calories overall, high intensity exercise ultimately results in greater fat loss–provided you are able to sustain the pace long enough.
Measuring Your Heart Rate
The easiest and most accurate way to measure your heart rate during exercise is to wear a heart rate monitor. Chest strap models that emit an audible alert when your intensity level drops below (or exceeds) your chosen training zone are the most convenient. If you don’t have a heart rate monitor, you’ll need to stop exercising to take your pulse. Place your fingers on the inside of your wrist or on your neck just below the jaw line and count the number of time your heart beats in six seconds. Use a stopwatch for more accurate results. Then simply add a zero to your total (i.e., multiply by ten) to arrive at your heart rate. Alternatively, you can count your heartbeats for ten seconds and then multiply the total by six.
Limitations
The maximum heart rate (MHR) that is used to calculate your target heart rate is merely an estimate. Our calculator uses the most popular formula (220 – age) to determine your maximum heart rate, but your actual MHR depends on factors besides age. Genetics and fitness also play a role, and your actual MHR could be as much as 15 beats per minute higher or lower than the number suggested by the formula. The most accurate way to determine your MHR is a max stress test during which you are hooked up to an electrocardiogram while running on a treadmill or performing other high intensity exercise.