The Fasted Cardio Debate

As You probably know, I’ve worked most of my life, or at least 28+ years professionally within the Health-, Fitness-, Gym-, Body Composition-, Sports-, Media- and Professional Athlete Industry, and one of the few websites I still randomly visit is T-Nation, and mostly because my old colleague from the 90’s, Christian Thibadeau, still writes for them on a regular basis.

A few days ago, their ‘Chief Content Officer,’ Chris Shugart, published the article “The Thinking Person’s Guide to Fasted Cardio.” As I’m currently 69 hours into my dry fasting of a total of 89 hours currently in a fasted state, with another 45 hours to go, I thought it appropriate to write about this subject, as every long dog walk I currently undertake three times a day, would be considered “fasted cardio.”
Now, including the word ‘thinking’ in that title is a bold move, let’s see if he lives up to it.

The big question within the “fitness industry” and among the gymrats and muscleheads concerning ‘cardio,’ as in ‘cardiovascular-dependent exercise,’ has always been if this type of exercise is best done in a fasted state for achieving fat loss, as in in the morning after sleeping, or later in the day after having a meal or two.
Some of you might remember my article from 2006, where I totally destroyed every argument for doing “cardio” all together, as I never used it with my own clients. However, the indoctrination and the bro-science mentality is quite strong within this industry, and most athletes just seem to love wasting their time with such nonsense. With that said, there’s nothing wrong with enjoying walks or even bike-rides in nature and at the same time expending some energy from your fat stores, however, scheduling it or using equipment at the gym for 30 to 60 minutes instead of being outside, when you actually would rather do something else, only because you believe it will get you in “shape” a little bit quicker, is really sad and foolish.

Anyway, let’s see what Mr. Shugart has to offer on the topic.
He begins with explaining that there are pro and cons for both scenarios, and that one could easily use “science” to convince any athlete to either side.
And yes, that is true. However, most science is complete bollocks, and we’ll get to that.

As for fasted cardio, Shugart continues with stating that, “When you wake up in the morning from an overnight fast, you’re primed to expel body fat to fuel a cardio workout. Metabolically, your body is optimized for lipolysis (breakdown of stored fat) and oxidation (the “burning” of that fat).”
This is also true, but very much depending on how you actually would define an “overnight fast.” Most people only sleep for 7 hours or less, and many have a late meal or snack, only an hour or two or so before bedtime. An average meal will take at least 5 hours to digest, and a snack close to 3 hours. So, if you count the hours from your last meal before bedtime and until you wake up and do your cardio, you’ll have to subtract the hours of digestion depending on the size of your meal. Those into fitness are usually brainwashed to eat right before bedtime, as they are afraid of “catabolizing” muscle mass during the sleep. Some idiot-bodybuilders even get up at night to have a protein shake or snack, which is incredible stupid as sleep and achieving a fasted state is crucial for your body to be able to recover, repair and detoxify.

So, with this in mind, I would say that at least 90% of all people never really reach what would be defined as a real ‘fasted state’ after waking up, as that would actually require 8 to 10 hours (or more, if your digestion system is compromised) without food after digestion from the last meal has been finished – which means waiting 11 to 15 hours from your last meal. If you get up at 6 AM and do your cardio, in order to actually be in a fasted state, your last meal have had to been at least no later than 5 PM the previous day. Personally, I do not know of any indoctrinated gym-goers being without food for that long, except for my own clients of course.
And this is why most studies on this subject is completely useless, and so are most anecdotal stories.

Anyway, Shugart cites some studies and the bottom-line is that those allegedly doing ‘fasted cardio’ lost on average 1% more body fat than the group doing the same cardio in a ‘fed state.’ Again, I bet that most people in that “fasted” group where not really fasted, as in going at least 13 hours without food.

He then ventured into the ‘con side’ of doing fasted cardio, as in the risk of losing muscle mass due to increased levels of cortisol. Remember, cortisol is naturally released in the morning to wake you up and to metabolize energy so you can get food and fuel your body with nutrients. Now, being in a true fasted state actually protects you from cortisol as growth hormone increases, and so does testosterone a tiny bit if you’re healthy. However, if you’re not in a real fasted state yet, and exercise when cortisol in naturally high, it might indeed increase the risk of muscle tissue being broken down, as in ‘catabolism.’

Also, all kind of exercise is stress on the body. When you eat something, the concentration of amino acids in the blood will increase, and this will keep you in a ‘fed state’ protecting you. Once the meal has been fully digested, after 5 to 6 hours or so, levels will start to decline and after a few more hours you are no longer ‘protected,’ not until your body is in a true fasted state and upregulates the use of body fat and tap into autophagy, the recycling of damaged cells which provide the body with an abundance of amino acids.

Shugart actually quotes Chris Thibadeau on this, where he points out the risks with doing “fasted cardio” in the mornings. And yes, unless you truly are in a fasted state, it will be an unnecessary stressor and you might end up using some muscle tissue as extra fuel. Unfortunately, Shugart does not explain this, most likely because he does not have the knowledge or understanding of our physiology and fasting.

Also, if you fast and still consume water, or any liquid, your body will interpret that as being fed, as your stomach and digestive system is activated to handle that liquid – and during that time, fat metabolism is halted and you are not as protected if you exercise as it forces the body to use gluconeogenesis to make glucose from muscle protein. This is why dry fasting is vastly superior, and why it’s almost impossible to lose muscle mass while dry fasting, while it will likely happen while doing prolonged water fasting. This also means that if you do morning ‘fasted cardio’ and drink something before or during, you set yourself up for even more problems as you increase the risk of muscle loss even further.

So, there you have it. Shugart was on the right track, even though he did not really understand the physiology behind it. To conclude, if you’re a muscle head and actually understand what a real ‘fasted state’ is, and apply it by not eating anything late in the day and then do morning exercise before having your first meal, make sure you do not drink anything until finishing your ‘cardio’ or whatever.

And if you’re a ‘thinking’ man or woman, do not do any kind of cardio if you need to lose a bit of fat weight. Instead, make sure you consume a highly nutritious diet of animal-based foods, and then do strategic dry fasting to quickly “burn” that fat all while reaping amazing health benefits and bodily repair. Read more about that here:

And more about dry fasting here:
And here:

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