Welcome back to Let's Chat, Myths! In this episode, we explore whether training/exercising on an empty stomach/fasted state is a good or bad thing. It's not as simple as it sounds and we find it's very individualised/complicated!

 

We begin by going into the realms of "The Diets" by discussing intermittent fasting. Tom has done this previously so he tells us of his experiences and how he felt from not a training standpoint but losing weight and the convenience factors. 

 

This took us onto a claim that those training while fasted/empty stomach like to make. Because we are training with low glycogen stores our body is forced to tap into our fat stores for energy. So while this is true yes, as long as you're in a consistent calorie deficit you will lose fat regardless of training fasted or not. Not only that but from a performance standpoint, you will most likely perform worse than if you had eaten before. 

 

However what if you can't exercise after eating for at least 2 hours because it makes you feel sick etc and you simply don't have the time to wait? Then unless you have been allowing the body to adjust to increasing intensity over time then we'd recommend you keep it light. As we mention we wouldn't personally do anything too intense without eating prior but this is why this topic is so individualised as some may find it ok to do intense training on an empty stomach. Evidence does suggest that eating prior will improve performance, however.

 

We also discuss EPOC (afterburn effect) and why it may be overexaggerated. This is something that happens after you exercise. So the continuation of extra calories being burned. There was a study which claimed this afterburn effect is heightened by eating before exercise over not eating. This is linked down below. Although this may be true it was hard to tell by what extent and from what we know it's most likely not a significant amount. Perhaps the reason this "afterburn" effect is heightened due to eating before is actually improving performance output so working harder, therefore, burning more calories. Once again this is all very personal to individuals. 

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Studies mentioned:

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Effects of fasted vs fed-state on exercise on performance

Eating before Increases EPOC

EPOC after cardio

EPOC resistance training

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