Fasted cardio: a necessary evil or pointless badge of honor?
Many moons ago fasted cardio was a popular tool used by bodybuilders, with the purpose of gaining that extra edge for fat loss.
For those who are not sure what fasted cardio is, it is simply getting up and doing some cardiovascular training (often walking, cycling, running…you get the idea – before having any breakfast.)
Skip forward a few years thanks to the internet and social media fasted cardio has grown in popularity and is a mainstream fat loss protocol.
So how does it work and do we need to do it?
I mean we all know you need to suffer to lose weight and the harder it is the better it must be right?
The premise of fasted cardio is sound. When you do not eat anything for a few hours (especially after an overnight fast) the body predominantly burns fat for fuel at low intensity and stored carbohydrates at a higher intensity.
So the people who argue the benefits of fasted cardio are not technically wrong, you are burning more fat when you are exercising.
But unfortunately, this is as far as it goes. Burning more fat as fuel is not the same thing as body fat loss. Not to get too technical, the term is called fat oxidation. And whilst there might be some certain people who might benefit slightly from fasted cardio for other reasons (those with PCOS or the metabolically inflexible) fasted cardio doesn’t seem to live up to the hype.
Whilst it is true you might burn more fat at the time we often see a greater suppression of fat oxidation at a later time in the day when food is eaten (more food is stored as a counterbalance.)
The only way to lose body fat is via calorie deficit. Just in case I will repeat that – you need a calorie deficit to lose body fat, no matter how you wish to measure it.
If you eat food before you train you will burn more of that food during the session and store less later. If you train fasted you will burn more fat but store more of the food when you eat it later, providing the mounts are the same. The body is pretty clever and adaptable like that and for the most of it, it tries to balance out.
So do you need to do fasted cardio for better fat loss results?
Not at all. If you prefer to rather sleep in (like I do) and do it a later time, then do that.
But maybe it is only time you can get it done, or you don’t enjoy training on a full stomach that early in the morning.
Just remember it doesn’t make you hard-core or better off by doing it, it just gives you something to post on your IG page.