05/09/2026
“Fasted cardio burns more fat” is one of the most repeated pieces of fitness advice… and one of the least true.
Here’s what’s actually going on: when you train fasted, your body still has plenty of fuel to draw on (stored glycogen, body fat), so it’s not like it “runs out” and switches to pure fat-burning mode the way people imagine. What the research actually shows is that fat loss over weeks and months comes down to your total energy balance (calories in vs calories out) not whether you had breakfast before your 7am run.
What fasted training often does do is make the session feel harder, because you’re low on immediately available energy. That can mean you move slower, lift less, or cut the session short, all of which work against the progress you’re trying to make.
We’ve also all been aware of people fainting at the gym - often out of nowhere it seems. Here’s what happens: physical activity burns glucose rapidly, causing exercise-induced hypoglycemia (low blood sugar). When your body lacks food before a workout, your blood sugar can drop below normal levels. Your brain and cells lose their main source of energy, leading to sudden dizziness or a loss of consciousness.
So, we’d absolutely prefer that you eat before you come in.
If you’ve been skipping food before training because you thought it would speed things up, try the opposite for a week: a small carb-based snack 30-60 minutes beforehand, and see how your energy and performance change. You might be pleasantly surprised. 🥰