USA Physique
The Coaching Authority

Calories Burned

Calculate the Calories Burned By Heart Rate

Burning more calories become easier with a better knowledge of the connection between the heart rate and the metabolism process.

Metric Imperial
Calories Burned
These calculations are based on averages.

The Fat Burning Zone

The fat burning zone theory seeks to help adherents lose weight by tapping on the body’s fat storage rather than glycogen. They argue that the body burns a greater percentage of fat with lower-intensity exercises than at higher intensities because the body does not require ‘fast energy’ from glycogen. As such, this theory promotes longer and lower-intensity cardio workouts that maintain your heart rate within the ‘fat burning zone’.

However, that is a bit of a misconception. While it is true that the body burns fat during low-intensity workouts, the fat burning rate remains low and you have to exercise longer to burn the same amount of calories you would at higher intensities.

In a high-intensity workout, although your body uses your glycogen stores first for ‘fast energy’, it depletes the glycogen stores rapidly enough to force your body to tap on the fat storage. This means that high-intensity workouts are more efficient in burning way more total calories – both glycogen and fat calories. Ultimately, the total number of calories you burn leads to the most weight (and fat) loss.

30 Minutes of
Fat Calories
Glycogen Calories
Total Calories
Low Intensity Group (50%) 120 80 200
Hight Intensity Group (75%) 140 260 400

Zone One

The first zone is about 50 to 60 percent of your max heart rate. That’s the least intense zone of cardio and is relatively easy. If you’re new to exercise you should start your workouts in this zone. You’ll burn some calories and build up your cardiovascular system to prepare yourself for harder workouts.

Zone Two

Exercise at 60 to 70 percent of your max heart rate and you’re still in a relatively low-intensity zone. Some people will be in this zone when they jog slowly. It’s slightly more intense than a brisk walk. If you stay in this zone during your workout you won’t be exhausted after your workout. You might even feel refreshed afterwards.

Zone Three

Between 70 and 80 percent of your max heart rate constitutes zone 3 — the perfect zone to train for endurance activities. When you run distances or participate in other events such as a triathlon, you’ll spend a lot of time in this heart rate zone. It’s low-intensity enough that you can maintain it for quite a while, as long as you’re trained.

Zone Four

Zone 4, or 80 to 90 percent of your heart rate max, is too intense to sustain for a long time. You reach this zone when going at a quick running speed, just below an all-out sprint. This is a heart rate you would hit during a circuit training workout or while doing interval training, where you work for a short 30- to 90-second burst and then rest.

Zone Five

The final zone, which is 90 to 100 percent of your max, is the most intense. It’s incredibly hard to sustain your workout at this heart rate. Most likely this will be the heart rate zone that you hit at the end of an incredibly hard sprint. Your body will quickly hit a wall where you can’t push any hard and start to slow down.