Many people are confused by the difference between a peak (maximum), cardio, and fat burning heart rate. I’m not one to judge. The names can be very misleading and seeing them on gym equipment or fitness tracker apps can make us think our goals are different from what they really are. I’m hoping to clear up this misunderstanding to help you to know your workouts are what you expect them to be.
Your Fat Burning Heart Rate Doesn’t Torch the Most Calories
Here’s where things feel frustrating when it comes to reading your cardio and fat burning heart rate. So, you head out for a walk wearing your trusty Fitbit, or hop onto the elliptical at the gym, and check out the graphic on the heart rate monitor. You’re barely above a stroll but look at that! It says you’re right in the fat burn zone! Awesome! Since weight loss happens to be your goal, why would you ever try to increase your intensity? You’re just where you want to be, right?
This makes so much sense, but it also makes me feel like my head is going to explode. It would be great if the names of these zones were just slightly less misleading.
Your fat burn zone is usually achieved in a low-intensity workout. It’s just slightly above your resting heart rate, at 55% to 65% of your peak/maximum. The cardio zone, on the other hand, is about 75% to 85% of your maximum.
What’s in a Name?
There are many kinds of benefits that you can achieve from exercising. Mental health advantages, balance, musculoskeletal, and so on. That said, if cardiovascular or weight management targets are anywhere on your spectrum, you’ll need to achieve a certain calorie burn. You’ll need to get your heart pumping and your respiration increasing.
Here’s where things can feel a bit bumpy at first. The truth is, your body does increase its use of stored body fats as a main energy source when you’re in the fat burning heart rate zone. That said, this is only compared to your resting heart rate. So, in essence, this zone marks where anything really starts happening at all. Unfortunately, it represents a very low calorie burn. If you’re hoping to get fit and torch some unwanted body weight, you’ll need to work harder!
Cardio is the next level up. You’ll burn more calories, your heart will beat faster, and you’ll breathe more quickly. If your workout is intense enough, you’ll even achieve an “afterburn” effect, which lets your body continue chomping through those calories for a while even after you’re done your workout.
Getting the Most Out of a Fat Burning Heart Rate and Cardio
A good body of research has found that an efficient way to use both your fat burning heart rate and the cardio zone to your best advantage is to continually swap from one to the other. For most of my clients, this means high intensity interval training (HIIT) or an alternative version of it like Tabata.
These types of workout alternate higher intensity activity with lower intensity activities (or even brief rests). This causes your body to alternate among your fat burning heart rate and cardio, even adding moments approaching or reaching a peak/maximum. This allows your body to burn calories the most efficiently while still telling it to use stored body fat as a top fuel source.