Everything You Need To Know About Intermittent Fasting As A Bodybuilder

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The ins and outs of intermittent fasting.

In an ever-evolving world filled with social media influencers promoting all different kinds of diets and supplements amongst other products, it’s much too easy to come across misinformation and fads that have sprung up over the recent years, however, intermittent fasting isn’t one of them. These trends are either brand new or are simply “refurbished” and brought back into the limelight, this time with a fitness-related spin on it.

One of the diets, or should I say eating patterns (more on that later), that has risen in popularity the most in the health/fitness space is intermittent fasting, often abbreviated to IF.

We all know that fasting refers to the abstinence from food, but what else does it entail? And is it even beneficial to those looking to gain muscle and make overall improvements in their body composition?

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What is Intermittent Fasting (IF)?

We first have to know what exactly intermittent fasting is. There are various protocols that exist for IF. Some of them include alternate day fasting, which is when you simply fast every other day and eat normally during your non-fasting days. Another type of IF that exists is the Warrior Diet, which is when you fast all day and eat all of your allotted calories in one sitting, usually at nighttime (1).

However, despite all of the different protocols out there, the type that’s most commonly used in bodybuilding and fitness circles is the 16:8 protocol, also known as time-restricted feeding.

This is when you fast for 16 hours and then you have an 8 hour “feeding window”, where you consume your daily calorie allotment. Since this is the most popular type of fasting in the fitness industry, this is what will be referred to when the abbreviation “IF” is used.

But one thing to remember here is that IF is not a type of diet, technically. It is actually a type of eating pattern, as mentioned earlier. The goal here is to consume the same number of calories and macronutrients that you would consume if you were following a standard meal schedule. The only aspect of your nutrition that you’re modifying here is meal frequency, not types or quantities of food.

The times that one would have their fasting and feeding windows are completely up to the individual, hence one of the reasons why this diet has become so popular. It allows people to be able to make mealtimes conform to their schedule, rather than trying to force smaller, more frequent meals, which has been often promoted in the fitness industry as of late. With our busy schedules, we shouldn’t have to stress about our meals.

This higher meal frequency theory comes from the common misconception that eating more frequent, smaller meals will speed up your metabolism (2), making you burn more calories at rest. This is simply not true. What matters the most about nutrition regarding body composition goals are the total amount of calories that are consumed, not how often you’re eating.


Should Bodybuilders Use Intermittent Fasting?

From a general health perspective, there are some good reasons why bodybuilders should use intermittent fasting. Both animal and human trials have supported data that illustrates a reduction of risk in overall metabolic disease when time-restricted feeding was utilized (3). Common biomarkers used to assess risk of metabolic disease such as triglycerides (cholesterol), glucose, insulin, and tumor necrosis factor alpha were all shown to be significantly lowered in those who followed IF compared to a traditional meal plan.

However, there have been several issues with the current literature that exists for IF. First and foremost, most of the literature that exists on it to date utilizes subjects that are overweight or obese. This means that we can’t compare these studies to more athletic populations such as bodybuilders to get an accurate assessment.

Also, many of the studies don’t match groups for calories and protein. This is significantly important to do, because if this is not done, it brings about more of an “apples to oranges” comparison, rather than bringing about an equal and fair association between groups.

Fortunately, there was a study that was released in 2016 that solved many of these existing issues. This study showed positive body composition adaptations when following IF. In this study that utilized resistance trained males, those who followed IF showed a greater decrease in fat mass compared to those who ate a standard diet (4). Both groups were able to maintain their muscle mass to a similar degree, as well as maintain the same resting energy expenditure, or in other words, burn the same number of calories at rest.

What was particularly interesting about the aforementioned study was that it failed to support the findings of many other studies out there involving the reduction of risk of metabolic disease. This suggests that these findings may or may not exist for athletic populations, or for those who are generally healthy. Unfortunately, there isn’t enough data out there to draw a solid conclusion on this matter as of yet.

Even though not all of the studies on this matter have not been structured with the same methodology, there is a very important aspect about IF that many of these studies can tell us. In another study with resistance trained males, there were two groups like usual; an IF group and a normal diet group. However, the study had no limitations on the quantities or types of foods eaten (5).

Although this may seem like a very unorganized way to conduct this study, the result from doing this was quite profound. Those in the IF consumed on average 650 less calories per day compared to the normal diet group. What this conclusion can tell us is that using IF in one’s diet plan may make it easier for those wishing to lose body fat, as the act of fasting appears to prompt them to eat fewer overall calories throughout the day.

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Intermittent Fasting Benefits

Some more of the practical benefits of intermittent fasting include:

Food Control

With intermittent fasting, it is much simpler to control how many calories that you’re eating. This is because it is much easier to pair foods together, like your proteins and carbohydrates, when you have more calories to “play with”. And as mentioned earlier, it is much easier to plan your meal times around obligations, such as work and school.


Following IF is simply a more convenient pattern of eating for some people, particularly for those who maintain very busy schedules.

Let’s look at an example of a person who follows a more frequent pattern of eating. In order to follow this diet successfully, further planning must go into it, as more meals have to be prepared compared to somebody who follows an IF plan. And going off of the previous point, especially if you’re in a calorie deficit, in can be much more difficult to be creative with your food pairings, as you only have so many calories to work with.

Because of this, boredom with the diet may set in, and you may fall off the wagon sooner rather than later. If you can’t stick to the diet, then you will inevitably fail, no matter which one you choose (more on this in a little while).

How to Properly Use IF in Bodybuilding

Now that we know how IF has been used in the scientific literature, we can know talk about how to implement it in your plan if you so choose.

Again, as we spoke about earlier, we’ll stick with the traditional time-restricted feeding model, otherwise known as the 16:8 protocol, as it is the most commonly used format of IF in fitness realms, and now you’ll find out why that is.

This is the most commonly used protocol, especially in bodybuilding, as it allows the individual full control of the planning of their meals, particularly around their workouts. The pre and post-workout meals are often regarded as the most important meals of the day. Most traditional forms of IF would not allow this type of flexibility and control.

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Getting Started

The first thing we need to do when we begin an IF plan is when we should figure out when our fasting periods and our feeding windows will be during the day. For easier fasting times tracking, we recommend using intermittent fasting programs.

What I would recommend is using the time you commonly workout and basing your eating schedule around that. For example, if you commonly workout first thing in the morning, then you should fast all the way up until your post workout meal, and then continue eating for the next 8 hours. Let’s say you stop eating at 7 P.M, then you would fast again until at least 11 A.M the following day, and then repeat.

What makes this work so well for people is that a big chunk of their fasting window goes towards the time they are asleep. Let’s say an individual gets an average of 8 hours of sleep per night, that’s half of the fasting window done right there!

An important thing to note here is that your fasting and feeding windows do not need to be perfect! If you’re a couple minutes off on one of your windows, it’s really no big deal whatsoever. It will not make that much of a difference in the grand scheme of things. Some people become so stressed about these little things that it takes away from the enjoyment of this lifestyle.

But How Do I Deal With The Hunger?

What many people have trouble adjusting to when first beginning an IF plan is dealing with constant hunger during their fasting windows. For somebody who has not gone without eating for that long before, it can often feel like an eternity.

But there are a few methods that will help you to work around this issue:


This popular stimulant, which is often touted as one of the best supplements for building muscle, can be one of your best friends when it comes to blunting feelings of hunger throughout the day.

Caffeine, but more specifically coffee, has been shown in the literature to blunt hunger responses throughout the day (6). Surprisingly, even decaffeinated coffee has shown this response as well, albeit to a slightly lesser degree. What this means is that there are potentially several ingredients in coffee besides caffeine that have the ability to inhibit feelings of hunger. Advanced Caffeine pills contain B-Complex vitamins, helping to restore your levels of B-Vitamins that caffeine intake depletes. Taking into account the fact that coffee depletes your B-Vitamin levels without replenishing them, caffeine supplements containing B-Vitamins can be seen as ‘healthier’.

Fat Burner

In addition to a well-adjusted fasting period, fat-burners accelerate fat loss by enhancing metabolism, reducing cravings, and increasing intra-workout energy. The best ones even go the extra mile to protect against muscle breakdown.

The right fat burner can accelerate metabolism, increase mobilization of stored body fat (to be used as energy), fight against hunger and cravings, reduce muscle breakdown, improve lean body mass and keep you healthy overall.

Although there is no magic pill, most value products combine high-quality ingredients with a proven track record. Our list of highly recommended fat burners rate, research and test brands to ensure you only get what’s on the label, and nothing more. Testing for purity, quality, and safety go hand in hand with assuring you have the best possible fat burner on hand. Even more important is having third-party tested supplements in a lab for individual ingredients that are all-natural, free of synthetics, and additives.

Zero-Calorie Carbonated Beverages

It’s pretty obvious as to why this can help keep feelings of hunger at bay. Drinks such as seltzer water can help you stick to the allotted time of your fasting window due to the fact that they taste great and the carbonation fills your stomach with more air, stretching the stomach. This gives you the feeling that you’re becoming full.

Again, just like with the coffee, please make sure that the beverages that you’re consuming are actually zero calories, and don’t contain any added sugars, which again, can “kick you out” of your fast.

And as a note, there’s a common notion out there that artificial sweeteners raise insulin and blood sugar. While this may have been shown to be true in some animal models, results are largely negative, or at the very worst, inconclusive, in human trials (7). Therefore, you most likely don’t have to worry about artificial sweeteners breaking you out of your fast. However, if you want to be extra safe, then I suggest not consuming anything with artificial sweeteners in it during your fast, such as diet soda.


This is probably something you don’t want to hear, and I completely understand that. But this needs to be said. Some things simply take time, and IF is no different. Many people find that it only takes them a week to adjust to the diet, while for others, they may never be able to without being in complete misery.

Remember, IF is not for everybody, nor does it need to be, as metabolic rate does not appear to be affected by meal frequency (8).

What matters most is adherence. Adherence, or basically how well somebody can stick to their diet, is perhaps the most important aspect of fat loss (9). Researchers speculate that this is more important than the diet itself, as a lack of adherence is the primary reason why many people fail to lose body fat.

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The Anabolic Cap

There has been a proposed theory out there by nutrition scientist Layne Norton that states that there is a limit to how much protein the body can use at any one time for anabolism, or growth (10). To put it simply, there is a minimum amount of protein that the body needs in order to initiate protein synthesis, as well as a maximum amount of protein that the body can use in order to keep this process going. After that, there is a large point of diminishing returns, where any extra protein won’t serve any more of a benefit for muscle growth.

Norton states that it may not be feasible to “make up” for a low protein intake during one part of the day by eating copious amounts of protein at a later point in the day. This casts some doubt on those following IF, and whether or not they are maximizing their growth potential.

Because of this, Norton offers a compromise. This “modified fast” that he proposes has the individual consuming protein at evenly distributed points throughout the day, while simultaneously restricting carbohydrates and fats. This makes it simpler to reach your protein targets, while still being able to enjoy larger amounts of food throughout the day. However, this type of fast has not been studied in the scientific literature. It is not clear whether or not the person following this version of IF would receive the same reduction of risk of metabolic disease compared to a person following a traditional time-restricted feeding window. So, more research is certainly needed here.

Final Words

Well, there you have it! Everything you need to start your intermittent fasting journey! If you take away anything from this article here today, it is this; intermittent fasting is not magic. Yes, I know it sounds silly, but it is simply a pattern of eating. There are no magic foods to help you lose fat faster. The two things that matter the most are the number of calories you’re consuming as well as if you can adhere to the diet or not. As long as you have those two variables under control and you are genuinely enjoying the intermittent fasting lifestyle, then I promise you that you will succeed at reaching your body composition goals.

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  1. Coller, R. (2013). “Intermittent fasting: the science of going without”. (source)
  2. Paoli, A.; et al. (2019). “The Influence of Meal Frequency and Timing on Health in Humans: The Role of Fasting”. (source)
  3. Rothschild, J.; et al. (2014). “Time-restricted feeding and risk of metabolic disease: a review of human and animal studies”. (source)
  4. Moro, T.; et al. (2016). “Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males”. (source)
  5. Tinsley, G.; et al. (2016). “Time-restricted feeding in young men performing resistance training: A randomized controlled trial”. (source)
  6. Greenberg, J.; et al. (2011). “Coffee, Hunger, and Peptide YY”. (source)
  7. H.; et al. (1989). “Aspartame and its constituent amino acids: effects on prolactin, cortisol, growth hormone, insulin, and glucose in normal humans”. (source)
  8. Schoenfeld, B.; et al. (2015). “Effects of meal frequency on weight loss and body composition: A meta-analysis”. (source)
  9. Gibson, A.; et al. (2017). “Strategies to Improve Adherence to Dietary Weight Loss Interventions in Research and Real-World Settings”. (source)
  10. Norton, L.; et al. (2012). “Protein distribution affects muscle mass based on differences in postprandial muscle protein synthesis and plasma leucine in rats”. (source)