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Fasting cardio eats muscles

Cardio im Fastenzustand frisst Muskeln

Here is a brief summary:

  1. Most people trying to lose fat will use diet and exercise strategies that make it impossible to maintain existing muscle mass.
  2. Fasting cardio works - but only if you use performance-enhancing supplements to protect your muscles. For the natural exerciser, however, it is counterproductive.
  3. If you decide to include cardio in your program, use low-intensity cardio for 45 to 60 minutes or high-intensity cardio for 15 minutes or less.
  4. Forgoing training nutrition is counterproductive when it comes to energy expenditure and maintaining muscle mass.

More muscle = higher metabolic rate

Whenever people decide to lose body fat, they make the same stupid mistake: they adopt strategies that make it impossible to maintain their existing muscle mass.

Of course they lose weight, but often they lose just as much lean muscle mass as body fat. They simply become thinner versions of their unattractive selves. Sure, they'll take up less space and the scale will tell them they weigh less and their doctor may even congratulate them on being closer to their healthy weight, but in reality they don't look any better than before, which defeats the purpose of weight loss.

The top priority when trying to lose fat should be to maintain existing muscle mass. Losing muscle mass should be completely unacceptable. If you lose muscle mass, it will be harder to continue to lose fat consistently, as muscle tissue is metabolically active tissue, which from a metabolic perspective is responsible for most of the fat you lose.

5 kilos of muscle burn 50 kcal every day at rest. So if you lose 5 kilos of muscle, you will burn 50 kcal less every day, which adds up to 350 kcal per week. Although this may not look like it at first glance, it will make a significant difference in the long run.

And then there's the issue of insulin sensitivity. If you have more muscle tissue, then your insulin sensitivity will lean more towards building more muscle mass. A larger muscle has more insulin receptors, which makes the muscle more insulin sensitive.

This means that you will tend to store more of what you eat in muscle instead of fat tissue. Lastly, if you have more muscle mass, you will be able to move more weight and train harder, which will increase the amount of calories you burn during a training session.

As you can see, it's not just important to maintain existing muscle mass while dieting - it's crucial. Here are the biggest mistakes people make when trying to lose weight:

1. cardio training while fasting

Fasting cardio, usually done first thing in the morning, has been a popular approach in the bodybuilding world for many years...and it works - if you're using performance enhancing substances to protect your muscle mass. For a natural trainee, however, cardio training in a fasted state is a very good way to lose your hard-earned muscle mass.

First of all, cortisol levels are highest in the morning (this is due to the cortisol surge that allows you to have energy after waking up). If you don't eat, your cortisol levels will remain elevated and even continue to rise.

And if you combine this with cardio training, which also tends to increase cortisol levels, then you'll end up with extremely high cortisol levels, which is the best way to lose muscle.

But not only that - if cortisol levels rise high enough, you'll have a hard time bringing them back down during the day. In other words, you'll spend the entire day in a muscle-depleting state!

I am neither pro- nor anti-cardio training. Some people need it to get super lean, while others don't. However, I think people use it too early in a fat loss phase. And if you do decide to use cardio to get leaner, it's a bad idea to do it in a fasting state.

The absolute best way to achieve the greatest calorie burn from cardio training throughout the day is to do it in a post-absorptive state. This means neither in a fasted state, nor in a state where you are still digesting food.

The post-absorptive state is the period of time during which nutrients are still present in the bloodstream while fat oxidation and calorie expenditure are at their highest.

When you perform cardio training in a fasted state, total fat oxidation is significantly lower over a 24-hour period, which is probably related to the fact that the metabolic rate does not increase or remain elevated, but probably also has something to do with the fact that this form of training causes more fatigue.

You therefore instinctively end up reducing your activity levels during the rest of the day. And then, of course, there's the problem that cardio training in a fasted state is potentially catabolic for your existing muscle mass.

However, doing cardio after eating is no better. It will lead to less fat oxidation and more glucose oxidation - not to mention that most people will find it harder to exercise intensely while they are still busy digesting a meal.

The best option is to perform a cardio workout when your body has fully absorbed nutrients before the activity. Unfortunately, it's really hard to achieve this with solid foods. It's almost impossible to know how quickly solid food is digested. This will vary from person to person and for the same person even depending on the time of day.

I therefore use a whey protein shake or an EAA drink, which is absorbed quickly so that I can do a cardio workout quite soon afterwards and reap all the benefits of the post-absorptive phase. This increases the metabolic rate and helps me get lean faster.

To summarize, if you are trying to lose fat and are not using anabolic steroids, you should avoid cardio training while fasting. Do your cardio training during the post-absorptive phase and it will have the biggest impact on your fat loss over 24 hours.

2. lighter weights and higher repetitions

Maintaining strength or even building strength is the absolute best way to ensure you don't lose muscle mass. If you continue to move heavy weights while dieting, this will force your body to maintain its muscles as it will see that it desperately needs them to survive.

If you reduce the amount of weight you move, your body will assume that you don't need as much strength as before and that it's okay to lose some muscle mass. Why? Because muscles consume tons of calories every day and your body will therefore see them as expendable.

And then there's the second part of the mistake: increasing the number of repetitions. This is often done to define the muscle - too bad it's not possible. You can't make a muscle more defined - you can only make it bigger or smaller. To get more defined, you need to get rid of the fat covering the muscle while keeping the muscle big and full.

Some people aren't stupid enough to believe that moving lighter weights with more reps works, but they still do more reps simply because they think it will help them burn more calories and speed up fat loss.

That's fine as long as you've already done your heavy training. However, if you overdo it with the repetitions, this can indirectly reduce your muscle mass by impairing your recovery.

If you reduce your calorie intake, then inevitably your ability to recover after training will also decrease, so an additional load by increasing volume can lead to a regression in both performance and muscle mass.

And the moral of the story? Do everything in your power to at least maintain your strength while dieting - and this won't happen if you stop training heavy to focus more on pump training.

3. cardio training with consistent moderate intensity

If you choose to add cardio to your fat loss program, you have two options and they are at opposite ends of the spectrum: low intensity like walking or high intensity like sprints and HIIT

It's a hormonal thing. Moderate, steady intensity cardio - the type of cardio most people use to lose fat - will increase cortisol levels the most. This type of activity is just intense enough to increase the release of cortisol and also lasts long enough to increase it significantly.

Low-intensity cardio exercise, such as a one-hour walk in the park or something similar, will not be intense enough to stimulate significant cortisol release. It might even lower cortisol levels as it has a relaxing effect.

High-intensity exercise, on the other hand, can cause a strong cortisol release, but the duration of the activity is usually not long enough to lead to a truly significant cortisol release.

Use longer duration low intensity cardio (at a relaxed pace that allows you to maintain a conversation) for 45 to 60 minutes or high intensity exercise that lasts 15 minutes or less.

This is the reason I like Loaded Carries like walking with two heavy dumbbells in my hands. Three to five minutes is all you need to get an amazing fat-burning effect, while at the same time this workout has no negative effects on your muscle mass - it might even help you build some muscle!

4. reducing your food intake too quickly too soon

Losing fat and changing your body is an emotional issue - we want that dream body and we want it now - now - now! This attitude leads to the fourth mistake on our list: starting fat loss efforts too abruptly.

I've seen people start their diet with less than 50 grams of carbs and fat and only 1200 kcal per day. Add that to 90 minutes of cardio a day (sometimes 120 minutes a day split between two workouts), some circuit training and the use of a powerful fat burner formula.

Great - but how long can you keep this up? More importantly, how quickly will the body adapt to something like this...?

The body will get used to this level of deprivation and activity within 4 to 6 weeks and fat loss will slow or stop...and that's if you last the 4 to 6 weeks at all. You will feel depressed, suffer from unbearable hunger, have no energy and basically stop enjoying your life. And then there's the massive muscle loss that such an excessive approach will cause.

What happens when fat loss comes to a halt with such an approach? What can you do to get it going again? You have nothing left to remove from your diet and as long as you can't devote all your time to training, you won't be able to ramp up your activity levels (not to mention you won't have the energy).

You will be doomed. You will continue to lose fat, but your progress will be so slow that it will be very unlikely, if not impossible, that you will last long enough to reach your goals.

Avoid being excessive right from the start. Use the diet and cardio strategies that allow you to lose fat at an acceptable rate and train to maintain or increase your strength.

The more conservative you are while still achieving good fat loss results, the more options you will have when your fat loss eventually slows down.

5. increase the training volume

When someone wants to become more defined, they usually tend to add extra training to their program. He does this because he believes that this will help him shape the muscle by working it from every angle. Well, unfortunately, it is not possible to specifically shape or define a muscle. You can only make a muscle bigger or smaller.

Excessive amounts of training will not help you with this.

Can you make a muscle bigger by training more? Sure, if you are in a state of caloric surplus, but if you are in a caloric deficit, as is the case during a diet, your body will have a hard enough time maintaining the muscle mass it has.

Building a significant amount of muscle will be very difficult if you are a natural exerciser. Since you're not in a physical state conducive to building new muscle mass, performing additional exercises will only make you expend more energy - which in turn can make it harder for you to recover after a workout - and that's not exactly what we want when we're trying to maintain our existing muscle mass.

Some people will swear that doing extra exercises makes their muscles bigger. However, this is probably more due to inflammation of the muscle tissue (which naturally tends to increase during a diet as the body finds it harder to regenerate), which can cause the muscle to swell.

However, this won't last long and it won't be long before you lose the capacity to get a pump - and this is the first sign that you are starting to lose muscle. The idea is to focus on the heavy basic exercises to maintain strength. You should correct muscle imbalances and lagging muscle development when you are in a calorie surplus, not when you are dieting to lose fat.

6. eliminating carbohydrates from your training diet

This is probably the most common problem. I plead guilty to having done this too. For a long time, carbohydrates were seen as the enemy of fat loss. This was especially the case during the low-carb hype a few years ago.

No one was as carbophobic as I was, so I can well understand the impulse to give up carbs before, during and after exercise in one fell swoop while dieting.

However, the absolute best insurance policy when it comes to maintaining (or even building) muscle mass while dieting is to use supplements during the training window that contain fast-acting carbohydrates.

During a diet, it makes more sense to increase nutrient intake around training and then reduce carbohydrates and calories during the rest of the day. This will allow you to maximize fat burning.

Don't be afraid of carbohydrates during the training window. These will not be stored as fat and can actually increase the rate of fat loss by allowing you to train harder and thereby increase your metabolic rate more.

7. cardio training before bedtime

This was popular in bodybuilding circles after it became known that Ronnie Coleman did this during his preparation for the Mr. Olympia.

Performance enhancing substances change your physiology. Steroids/androgens and cortisol, for example, share the same cellular messenger. Without giving you a lesson in physiology, this means that the more androgens you have in your body, the lower the effects of cortisol will be.

Performing cardio exercise - especially cardio exercise at a consistent moderate intensity - will increase cortisol levels and in the natural human hormonal cycle, cortisol levels need to be at their lowest before bedtime. If you have high cortisol levels before going to sleep, you will find it harder to fall asleep and get a restful and regenerative sleep.

In addition, high cortisol levels before bedtime will turn your sleep phase into a 7 to 10 hour catabolic phase, which is not a good mix if you value muscle mass. To maintain your muscles and recover quickly from training and optimize your hormone levels and cycles, you should avoid cardio training in the evening.

It's simple

  1. Keep doing the basic exercises with heavy weights.
  2. Don't add additional workouts.
  3. Don't try to burn more calories by training with weights.
  4. If you choose to do cardio, choose low intensity cardio, high intensity cardio of short duration or loaded carries and make sure you are in a post-absorptive state. Also avoid cardio training in the evening.
  5. Try not to correct lagging muscle groups when you are in a calorie deficit. The best you can do is maintain or slightly increase your muscle mass - you can't make drastic changes during this phase.
  6. Don't sacrifice your carbohydrates around your training - increase the amounts instead.
  7. Start conservatively. Do just enough to maintain a good rate of progress - e.g. a weight loss of one kilo per week - so that you still have other weapons in your arsenal if your fat loss slows down.


By Christian Thibaudeau

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