The “fat burning zone” can be very misleading and I find a lot of clients have the wrong idea, therefore their training suffers because of it. Well no more!
The diagram above is the older version we all see on cardio equipment. I find it very misleading compared to the diagram below (diagram 2). As you can see the “fat burn zone” on diagram 1 is compared to as very easy to easy intensity on the diagram below, which it is. That doesn’t mean its easy to burn fat, it means your workout level is easy or very easy. Now we all know we aren’t going to get leaner and fitter if our workouts are too easy. Hopefully we all know that?? If not, you do now ha.
The maths and science of it all
The diagram is saying you will burn more fat if you work at an easy intensity (50-65%MHR), compared to working hard at 80-90%MHR.
At the low intensity fat burning percentage is more than carbohydrates. This is where it is misleading.
At 50%MHR you burn 60%fat and 40% carbohydrates
At 75% MHR you burn 35% fat and 65% carbohydrates
Now the harder you work though the more calories you burn, and we all know that we need to burn more calories than we consume in order to lose weight. This is to do with the energy scales.
So if we were to do the same 30minutes cardio the ratios would look like this:
|Intensity||Fat calories||Carb calories||Total calories|
So you can see you burn more calories working harder, and more fat calories at a higher intensity than at a lower intensity.
You will also increase in your fitness levels working at a higher intensity as you put more stress on your body.
The benefits also happen after working out at a harder intensity, because of the after burn effects of exercise (EPOC). So when you work harder your body takes longer to return to its normal rhythm. Therefore you can be burning more calories for an hour or two after an intense session. After an easy session though the body returns to normal pretty much straight away, with no after burning effects.
So next time you see the chart or press the “fat burn” programme button….. Think again!!
As always feel free to contact me for any help and support or to book your first training session.