Fasted vs non-fasted Exercise… 🏃🏼♂️
There’s a fair amount of confusion out there about whether you’re better off exercising fasted (on an empty stomach) or after you’ve eaten something (non-fasted) and whether one is better or worse for fat loss.
The confusion arises because people often talk about how exercising on an empty stomach increases fat oxidation. This then gets conflated with fat loss. Fat oxidation is the process of using fat for energy in the body. When you eat something the body secretes insulin to aid in the processing and metabolism of the food for energy and storage. Insulin reduces fat oxidation, so less fat is used for energy. So the argument is that if you haven’t eaten anything yet that day then you won’t have secreted any insulin and therefore fat will be oxidised and used for energy.
Whilst this is true – you will have more fat oxidation, it doesn’t actually mean more fat loss. Fat loss is dependant on overall calories consumed, on average, over the day/week/month etc. Even if you exercise before eating, you still need to have a calorie deficit for that day otherwise any excess calories will still be stored as fat. So It makes NO difference to fat loss whether you choose to eat before or after exercise.
For some people they prefer to exercise on an empty stomach, but for others they need some food in their system to workout. From a workout perspective if you haven’t eaten yet then you may find you fatigue faster and aren’t able to work as hard, so you may end up burning fewer calories. So it’s very much personal preference!