Training Myths: Fat Burning Workouts

What started out as good research has morphed into a great way to sell gym memberships. Or something along those lines.

It all started when researchers established that there are varied percentages of fuels (carbohydrate and fat) that participate in energy metabolism during exercise. With increasing intensity of exercise, there is a proportionally greater share of energy derived from carbohydrate. The reverse is also true – as the intensity level decreases, a greater percentage of energy is derived from fat.

The fat-burning workout was born. Go longer, go slower, “burn more fat”, and lose more weight.

This was followed shortly thereafter by “get a gym membership”. You can come in and do more longer, slower workouts on our cardio equipment. Oh, make sure you get a heart rate monitor so we can establish that you are in that “fat burning zone”.

What started off as good research to simply describe the relationship between fuel source and contribution to energy metabolism turned into something completely different. It gave people a “scientific” excuse to go slow, especially if their goal was to lose weight. It gave higher level athletes a “scientific” excuse to “build a base and burn fat more efficiently”.

There are a couple of forgotten elements in all of this. One is that weight loss comes down to overall caloric expenditure. With that said, more calories can be burned working at a higher intensity than a lower intensity for any given time, regardless of the fuel source. The other benefit of a higher intensity activity is that metabolism post-exercise is elevated long after the workout. At lower intensities, metabolism returns to normal levels shortly after the cessation of the exercise. So just going longer and slower and burning more fat is not the total story.

It is also important to keep in mind that tissues respond favorably to loading. They adapt to the imposed demands. If the demands are low, the responses are minimal. 

One of the primary limiters to endurance activities is the ability to maintain your blood glucose level during exercise. Using fat as a fuel is a very inefficient way to do so. Maintaining a steady supply of carbohydrate during exercise will ultimately help the athlete maintain their blood glucose, regardless of exercise intensity.

Make your training more effective and efficient by performing not only the appropriate exercise for the desired effect, but the appropriate intensity and parameters to attain an optimal effect.

Photo credits: pheezy