How to Critically Consider Metabolism Myths – Part 5


We’ve covered four metabolism myths thus far and our journey is far from over. We’re destroying those fitness lies that are keeping you from achieving your fitness goals.

Metabolism is a topic that tends to trip up the majority of people new to the fitness world and even a good few that have been training for years. We hear the falsehoods repeated so many times that we all start believing them.

Thankfully, an increased in published research is allowing us all to check the facts for ourselves.

Here’s another metabolism misnomer and some research that proves all is not what it seems.

Myth 5: Keeping Your Heart Rate in the “Fat Burning Zone” Will Boost Metabolism

This metabolic myth stems from an incorrect assumption that cardio boosts metabolism and by keeping your heart rate in the mythical “fat burning zone”, you’ll burn all the more calories.

Like the myth we discussed yesterday, there is some truth to this assertion and it’s the misunderstanding of how this works that causes the confusion.

The fat burning zone is said to be 55 to 65% of your maximum heart rate. By keeping your heart rate at this constant, while engaged in cardiovascular exercise, you’ll alledgedly burn the most body fat.

It’s also an appealing option to many because it means you don’t have to work as hard for increased body fat burning.

Total Calories Matter Most

Fat on fireUnfortunately (and we say that because we understand the appeal of working less hard to achieve more), fat loss is all about total calories and while a greater percentage of fat calories are burned in the fat burning zone, you’ll burn far more overall calories while engaged in more physically demanding workouts – and more fat as a result.

Research has proven that maximum fat oxidation occurs between 60 and 80% of your maximum heart rate. The research also recognizes an overlap of increased fat burning that occurs when you train harder.

When your heart rate is at 50%, nearly 60% of the calories burned are from fat. If you increase intensity to 75%, your fat burning decreases. You’ll see a small decrease in the percentage but by burning more total calories, you’re still burning more body fat.

Let’s look at an example:

A 30 minute low-intensity workout of fast walking might burn 300 calories. That means you could potentially burn 180 calories from fat.

If you alternate that same level of walking with a “hard minute” effort of about 80% every five minutes, you’ll burn quite a few more calories and easily be at 450 – 500 calories burned in the same amount of time. 40% of 500 is 200 calories burned from fat.

You’ve burned more total calories, more fat and though EPOC is minimal, it does exist and you’ll still burn a few more calories after the workout – by working more intensely.

Don’t get caught up in “going easy” while working out if it’s solely for fat burning purposes and you have the ability to go a little harder. Your hormones will respond to more calories and harder work every time.

The fat burning zone is a fat myth.

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