Weight loss myths: exercising on an empty stomach burns more fat

Eat or don't eat before training - what is more effective for maximising fat burning during exercise, or does it even matter? We've all heard it before, "exercise burns more fat if you do it on an empty stomach". Is there any truth to this or is it just another weight loss myth?


The Myth
Exercising on an empty stomach may (?) result in a greater proportion of fat stores than carbohydrate used to provide energy, however this does not translate to an over all greater weight loss. Most people looking to lose weight have tried this hoping for a quick weight loss fix but they soon realise that it doesn't magically result in greater 'fat burn' but instead an uncomfortable less effective training session. This drop in training performance as a result of exercising on empty could actually be detrimental to your weight loss goals.

The Facts
The timing of energy intake (food eaten) and energy output (exercise) is of little significance for weight loss - the total difference between energy in and energy out determines the extent to which fat is burned. Even if you were to burn a greater proportion of fat stores exercising on an empty stomach the energy consumed following will replenish whatever fat stores were burned if your energy intake is greater then expenditure. More carbohydrate burned during exercise results in less available to then be stored as fat but if energy intake exceeds expenditure there will still be excess energy to be stored. Get it?  The balance of energy intake and energy expenditure determines weight loss or gain regardless of meal timing or the energy source used during exercise. 


For the most effective fat burning results diet should focus on reducing total energy intake and exercise should aim to achieve maximum energy expenditure. The goal of meal timing should be switched from emptying the tank before exercise to optimising energy levels for the most effective training session. More energy to train hard means a greater energy expenditure during exercise and greater fitness results. Not only does exercising on an empty stomach reduce your training performance it also results in longer breaks between meals, slowing your metabolism and further slowing your weight loss.

So what to do from here:

• Eat 1-2 hours before exercise to ensure  you have adequate energy to get the most out of your training session and burn the most energy.
• Focus on controlling total energy intake across the day to ensure energy expenditure exceeds intake. 
• Eat small frequent meals every 3-4 hours spread as evenly as possible across the day. This includes before and after training.