An Understanding Of Intermittent Fasting

What is intermittent fasting? This article explores the benefits of intermittent fasting and provides several sample meal templates to help you get started.

Intermittent FastingAs time evolves so does the amount of information that has been researched regarding nutrition, meal timing, meal frequency, and the way we change our eating habits to suit our goals. In the bodybuilding/fitness world the most preached diet deals with eating multiple meals per day spaced 2-3 hours apart (usually 5-6 meals per day).

Well today I am going to give you a little insight on a very popular diet and eating lifestyle called “Intermittent Fasting”. Now I know you may be thinking:

Fasting? is this going to be good? It sounds counter-productive so how can it work? What are the benefits of fasting and will it be useful if I want to gain size or lose fat/weight?

Sit back, relax, and enjoy what you are about to read. For some of you it will be magical, for the rest intermittent fasting may not suit your lifestyle. The take away message from this article will be this: intermittent fasting is a lifestyle diet. It should suit your lifestyle and make your life easier.

Does everyone need to do it? Absolutely not. A lot of individuals who get on intermittent fasting find it is the best decision they have ever made because of the many benefits that intermittent fasting does offer. I am a huge advocate of the phrase “do not fix what is not broken.” For those who enjoy eating more meals per day and find it is a better suit for their goals, at least give this article a read because you will find some interesting information.

So where do we start with intermittent fasting? How does one go about intermittent fasting compared to eating more meals spread throughout the day? It's actually quite simple. Intermittent fasting (also known as IF) is based on a 16-8 fasting to feeding window. You fast for 16 hours and feed for 8 hours.

Do you need to always fast for 16 hours? No. Again this is based upon your lifestyle. The creator of intermittent fasting, Martin Berkhan, structured it this way as a starting point. Martin goes on to say that women can fast for 14-16 hours based upon their preference, and males can also fall into the same category.

Again the premise is as follows: this is a lifestyle diet. It should suit your schedule. If for some reason you can't fast 16 hours should you stress over it? Absolutely not. It's ok to occasionally end your eating window early if it happens to pass the 8 hour fasting mark.

Do you always have to eat within an 8 hour window? Absolutely not. If you want to fast for 20 hours and eat within a 4 hour window it's ok. Again, this is about personal preference and what suits your lifestyle.

It may sound crazy, but believe me, if you ever see the personal results of individuals who follow this lifestyle it is truly mind-blowing. Intermittest fasting works regardless of the eating window, be it 8-6-4 or so hours. It can aid those with very busy life schedules, as they find it easier to fit their nutrition in without having to prepare X amount of meals. They can eat when they have the time and it suits their schedule. 

So how does a day on intermittent fasting look? It can really vary. As stated by Martin Berkhan on his website, it pertains to how you break the fast (your first meal) and when you train. So I am going to give you multiple ways you can set this up.

Intermittent Fasting

Examples of Intermittent Fasting

First and foremost you can train in a fasted state. This sounds counter-productive, but it's really not once you understand the reasoning. Regardless if your goal is cutting, bulking, gaining size, maintaining, etc., these outlines will help you set up your training/diet.

Let's assume the individual below will feast or eat in a 12-8 p.m. window for each of our examples below. This is an 8 hour feeding window, and fasting will be from 8 p.m. to 12 noon the next day.

Fasted Training

Intake 10g of BCAAs before training and during your workout to help stimulate MPS (muscle protein synthesis). This will help your body to stay anabolic. Yes BCAAs do contain calories (while not labeled due to FDA Standards) but this is meant to be counted in your total calories for the day.

Meal one will come after your workout. How many meals you eat during the feeding window after that point is your choice. For example:

  • Fasting - Fast from 8 p.m. the night before till 10 -11 a.m. or so and take 10g BCAAs.
  • Train - Hot the gym and get your workout in.
  • Meal One – 1 p.m.
  • Meal Two – 4 p.m.
  • Meal Three – 7 p.m.

Key Notes: The initial BCAAs are to be counted towards your calories but that does not start your eating window. If you take a pre-workout supplement that contains carbs don’t stress. Martin Berkhan allows up to 50 calories in your fasting window. These may come from cream/sugar, etc. in coffee, or from a pre-workout supplement. So don't sweat it!

1-2 Pre-Workout Meals

Let's say you train after having a meal or two. Your setup might look like:

  • Pre-Workout Meal - 12 Noon.
  • Train
  • Meal Two – 4 p.m.
  • Meal Three – 7/8 p.m.

Or if you have two meals prior to working out:

  • Meal One – Noon.
  • Meal Two – 3 p.m.
  • Train
  • Meal Three – 7/8 p.m.

Intermittent FastingAgain these are all just suggestions on what you can do. If you want to have 4 meals in 8 hours go for it. If you want to have 2 meals in 4 hours then rock it out. It's your choice. These are just examples that you can follow.

Regarding calories, there are a few things that Martin Berkhan does advocate that you should take note of:

  1. The post-workout meal should contain the bulk of your carbs and calories. A good guideline to use is to eat at least 50-60% of your total daily calories during this meal.
  2. Pre-workout meals should be very light. Again, this is personal preference. You know what settles best in your stomach. On his website, I remember reading that Martin ate chicken, a small piece of fruit, and some veggies (around 400-500 calories). Something very small that gives you some protein and carbs to train and push through your workouts. If you train fasted disregard this information.
  3. On workout days Martin Berkhan utilizes a higher carbohydrate intake. He likes to cycle his carbs/calories. On non-workout days he drops carbs in addition to eating more fats (again this is his personal preference). In the end does it matter? Absolutely not. If you know you work well on higher carbs every single day then do that. If you want to keep your calories the same everyday then do that. If it makes your life easier. Remember this is a lifestyle diet that suits you and your schedule.

Now that we have a generic understanding of what intermittent fasting is, and how to set up a meal plan based off your day/work/schedule, let's continue on and talk about the benefits of intermittent fasting.

Benefits of Intermittent Fasting

Does fasting limit muscle building? Not really. You won't lose muscle. You are simply eating your calories in a pre-determined block of time compared to throughout the day using smaller meals.

You will be fasting in the morning and sipping on diet sodas, coffee, water, etc., until it's time to break your fast. What you drink is your choice. As stated earlier, if you want to add up to 50 calories of cream/sugar or other things to help you curb your appetite, rock it out.

At first intermittent fasting may be hard because your body is used to eating frequent meals (due to ghrerlin, the body’s hunger hormone) but this will adapt over time. To read more about your hunger hormone, Martin Berkhan has many studies on his site you can research and read about. Materials also include his recent article on the 10 ten fasting myths debunked.

I remember Martin saying the following regarding his feeding window/pattern:

"Believe it or not we are animals just like the rest of the world. We weren’t meant to wake up and just eat food. Where would this food come from? We would hunt to get food and then eat not knowing when the next meal would be."

In essence this is true. Think about cave men and how they rarely ate. Were some of them big and strong? Absolutely. Were some skinny individuals with little/no muscle? Yes. But again this comes down to being more strict on your diet. Think about bodybuilders who count calories and hit their protein, fat, fiber minimums daily. Now apply that to fewer meals and in a given time frame. That is intermittent fasting in a nutshell.

The 6 meals a day theory was based upon getting steady amino acids and protein in your system. This is true, but when your body is always burning food/calories it's not always burning fat, or working to keep you lean. Total daily calories is what matters most, not when and how you eat them.

Truth is that eating 6 a day meals provides no benefit over intermittent fasting when considering the preservation of lean mass, burning fat, making gains, increasing metabolism, increasing HGH, increasing serotonin levels, etc. Martin Berkhan does address all pertinent studies in detail, but I just wanted to give you a brief rundown on the diet and what it has to hold.

Here is another reason why I believe fewer meals per day is superior. Layne Norton has an infamous Muscle Protein Synthesis Study (MPS). In this study Layne showed how eating meals spaced 4-6 hours apart while dosing 5g of leucine (which can be found in BCAA products) maximizes MPS.

How is this possible? Well eating more often is actually counter-productive to muscle building and stimulating MPS because protein levels never get the chance to reach their refractory stages before being spiked again. So in essence the longer layover helps with maximizing MPS and utilizing the BCAAs between meals to spike protein levels, allowing longer durations between whole food meals.

As crazy as it sounds you can Google his research and read for yourself. Another nail in the coffin against frequent eating? Absolutely, and there is more research to support intermittent fasting. We have not even touched upon Alan Aragon and his research contained in the book Girth Control. This book is a great read, along with books by Lyle McDonald.

Intermittent Fasting and Supplements

Do we really need supplements? I would consider using BCAAs regardless if you're training fasted or not. I believe in them because of how fast they are digested in a free form state (instantly) compared to whole foods or whey protein, which takes several hours to digest.

What do we lose during training? Glutamine and aminos, if you are in a fasted state. These are essential when training on nothing. If you do have a pre-workout meal I would consider them optional, but I like being safe rather than sorry. So I do advocate BCAAs on top of the essentials:

These are to be taken on a daily basis. You should take these during your feeding window and not before or after it has been ended.

A few other suggestions I want to point out regarding training and cardio. Martin Berkhan is a big advocate of doing LISS cardio (low intensity steady state), or forms similar to walking. He advocates LISS during the fasting window; brisk walks for 20-30 minutes. These could be done for a few times a week (2-3 times).

Nothing crazy as far as speed or incline goes (if you wish to use a treadmill). Just get the blood flowing. If you were to perform HIIT cardio (high intensity interval training) Martin would recommend taking BCAAs prior to HIIT, or to perform it once the feeding window is broken (refer to fasted training above for the outline on the meal protocol). Depending on your overall goal (cutting/bulking/recomping) the amount of cardio will vary to suit your overall goal.

Training wise, Martin Berkhan has a huge outline on his website explaining RPT (Reverse Pyramid Training). But in the grand scheme of things this is a lifestyle diet, so any type of training that you find that suits you should take priority. Regardless of your split this is more based off meal timing and frequency than training wise, but I did want to touch on the subject.

Conclusion

There are a few other key points I want to address before I wrap things. If something comes up (say family wants to go out to breakfast or co-workers want to take you out) and it goes against your window... who cares, live your life.

Going off intermittent fasting for one meal or one day wont make or break you. Chalk it up as a loss and get back on the grind tomorrow. Count your calories if you can and move on. Sometimes life is more important than one meal given your goal and diet (someone may be in contest prep).

More in depth information regarding studies, research and information on intermittent fasting can be found at Martin Berkhan’s ste, www.leangains.com. It is filled with great articles backing up his data on fasted training, fasted cardio and fat loss, and many others that may interest you. This article is just a general synopsis to give you an understanding on how you could implement intermittent fasting yourself.

Intermittent fasting is based off a 16-8 fasting to eating window. Whether the individual wants to fast 16 hours or extend the fast, it is up to personal preference. Some individuals drag it out to 20 hours and enjoy 2-3 large meals in a very short window, while some enjoy the 8 hour span to space out their meals.

I highly suggest you sign up to an online food tracking program to help calculate and monitor your calories from your current meal plan, and help port it over to fewer meals per day (to suit intermittent fasting). A tracking program will help you keep track of your protein, carbs, and fat intake for the day.

The next thing you want to do is set up your eating window (as in the example I did 12-8 p.m.). If you have a late lunch at work, say 2 p.m., it could be the start of your eating window. This window could last as long as 10 p.m, or end earlier based off what is going on in your life.

There is a lot of speculation regarding the topic of meal frequency, timing, and nutrition, but Martin Berkhan does make a firm stance with his personal experience and clients that back his intermittent fasting lifestyle. Those who follow it are reaping the benefits, and will continue to preach how it may be the best thing they have ever done for the life and body.

Some people just enjoy feasting on larger meals, while others prefer to have more spread out meals per day. In the end this is only research, and it is only a suggestion. Give it a shot for a good 8-10 weeks and assess from there based on your mood, energy, and training!

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About The Author
Bob Kupniewski is a competitive natural bodybuilder and ex-athlete. After a MCL tear, he turned his life around with proper diet and training.

28 Comments+ Post Comment

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Posted Sun, 06/25/2017 - 11:14
Steve

Hi I'm going to start working out early am around 530. Now I will be training fasted so it is ok to sip on Bcaa's as you say in the article. My question is I'm doing the 16-8 fast. My eating window is from 1-9 Pm. So after my workout should I have a whey protein shake or will that break my fast? And if so should I just wait until 1 to have my first meal and just sip on more Bcaa's or just have coffee and water. Thanks

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Posted Mon, 09/14/2015 - 09:41
az85iz

Hi
Io really like MS for gaining information about my workout and nutrition, so thx for the informations you guys provide.
According to IF can you guys give example of each meal should contain and what kind of food should I eat?

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Posted Sun, 02/02/2014 - 19:52
Fabiano

I did intermittent fasting before then stopped for a bit, i am now starting again. i start morning with 2 cups of espresso, around 6;30- 7;00 then i have a pre workout at 12;30 before i hit the gym around 1-2 then when i get home around 3;30-5;00 i have my meal, is this a good plan?

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Posted Wed, 05/01/2013 - 04:48
Jakob

Great article ... can't wait to get started :-)

I'm thinking of this plan to loss weight / fat burn:
Start fasting 7 pm
Training 8 am
Meal One 11 am (at the earliest)
Meal Two 18 am (at the latest)

... meaning I'll be training in the fasting window
fasting window: 16-18 hours (depending on the particular day)
eating window: 6-8 hours
number of daily meals: 2 (Typically lunch and dinner. Lunch being the main course of the day)

Do you think this will work or is there something that are inappropriate regarding training vs. fasting vs. weight loss etc. ? ... It will probably fit my daily life :-)

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Posted Wed, 04/17/2013 - 07:31
Debra

I have insomnia. Am I not eating enough at night?

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Posted Thu, 05/16/2013 - 10:35
Ranveer

I've had it that my hunger keeps me up.

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Posted Sat, 04/06/2013 - 00:30
john

hi i have a question for ya... say i got up at 11am ate my breakfast and trained at 12pm and ate the all food i need up an till 6pm.. then didnt eat till 11am the next day would this still work??

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Posted Sat, 04/06/2013 - 00:27
john

hi i have a question for ya... say i got up at 11am ate my breakfast and trained at 12pm and ate the all food i need up an till 6pm.. then didnt eat till 11am the next day would this still work??

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Posted Mon, 03/25/2013 - 22:57
Logical

Berkhan did not create Intermittent Fasting. The concept of IF has been around since the 1940's.

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Posted Thu, 10/17/2013 - 15:11
Karl Roberts

Intermittent Fasting have been around for millions of years, if not, billions.

Martin Berkhan made it understandable.

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Posted Sat, 03/23/2013 - 18:59
Donna

Hi, I have a question! I work out around 6-7pm, but my last meal is around 4:30pm. I don't eat anything after my workout. I eat the next day at 8:30 am. You mentioned that the largest meal should be post workout, but I'm not doing that. Would IF still work the way I'm doing it?
Thanks.

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Posted Sat, 03/23/2013 - 18:59
Donna

Hi, I have a question! I work out around 6-7pm, but my last meal is around 4:30pm. I don't eat anything after my workout. I eat the next day at 8:30 am. You mentioned that the largest meal should be post workout, but I'm not doing that. Would IF still work the way I'm doing it?
Thanks.

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Posted Tue, 03/19/2013 - 09:50
Mark

also "cave men" just didn't hunt, they gathered nuts and berries,fish and some stored food (less sugar in those berries than now as well) were readily available. So to assume based on an episode of Captain Caveman that they were these idiots who never ate breakfast until after they hunted is bro science- there is no evidence for it anthropologically.

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Posted Tue, 03/19/2013 - 09:12
Mark

I see one immediate problem trying to use logic of "we are just animals" or "cave men" we are neither. Animals have completely a different genetic make up.Even if we are compered to our closest genetic animals, the amount of genetic data that differs is lie a set of encyclopedias even though the percentage may be small.We have not been hunters or gatherers for many centuries. Our bodies have changed and adapted to our way of life. Can we change those patterns? yes, but it doesn't mean one way or the other is somehow in our genetic make up to eat a certain way.If you start with the wrong presuppositions you will naturally come to incorrect conclusions. You may get lucky and find something that works but it is still irrational and illogical.

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Posted Sat, 02/09/2013 - 12:54
Steve887

"On non-workout days he drops carbs in addition to eating more fats ... In the end does it matter? Absolutely not" -- Absolutely wrong. Cycling carbs in this fashion is paramount to IF.
"I would consider using BCAAs regardless if you're training fasted or not." -- If you're not fasting, there's absolutely no benefit that BCAAs will provide.

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Posted Thu, 11/22/2012 - 03:40
Jordan

Any health website mentioning diet sodas as an option to drinks lose my respect instantly.

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Posted Mon, 03/25/2013 - 23:01
Logical

*facepalm* ASPARTAME WILL KILL YOU!!!
yeah...no...it won't buddy.
diet soda is fine in its own right

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Posted Wed, 11/14/2012 - 09:12
Sada

Hi,
I usually workout around 7pm in the night and eat at 8:30 pm. I do 2 days of HIIT Cardio,2 days weight training and 1 day of both. I take whey protein before workout and eat 5 times a day. I am thinking to follow this IF 16-8. How should i plan rest of meals? Will Whey protein (which has 5g of BCAA per serving )be enough or BCAA is a must?

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Posted Fri, 10/26/2012 - 20:35
Bob

Why take BCAAs before training on a fasted mode? You're growth hormone rises so much after fasting that your muscles are protected from becoming catabolic. No need for amino acids or protein I've used them all and they never made a difference, the only thing that helps and is not a waste of money in comparison with the previous supplements is creatine. That my opinion anyways...

-- BCAA"s require 0 digestion, they immediately put you into an anabolic state, hence why martin advocates them for fasted training, they help replenish what you will lose during training and going into a training session fasted is very catabolic especially while cutting and in a deficit.

I have one question, my day starts off training at 5:45AM - 7:00AM and I am home by 7:15AM cooking my meals. Would it be feasible to start the fasting at 8:00AM and end it at 4:00PM?

-- That is fine! Fit in the 8 hours and you are GOLDEN!

I've tried IF my day looks like this: up at 4:30 am don't eat till 10:30 then eat again at 1:30 train at 3pm eat again at 4:30.

- As long as you have an 8 hour window you are fine... do not over complicate make it fit your LIFESTYLE

Hey. If I was bulking would I just eat the same amount of calories in an 8 hour window as I would normally throughout the whole day? Thanks

-- Did you read the article? I wrote that in there about 4 times :) haha yup buddy!

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Posted Mon, 10/29/2012 - 17:20
Andy

Has there been a study that proves that ?

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Posted Fri, 10/26/2012 - 02:41
Andy

Why take BCAAs before training on a fasted mode? You're growth hormone rises so much after fasting that your muscles are protected from becoming catabolic. No need for amino acids or protein I've used them all and they never made a difference, the only thing that helps and is not a waste of money in comparison with the previous supplements is creatine. That my opinion anyways...

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Posted Thu, 10/25/2012 - 22:59
Kimbo

Great work Bob! Michael - thats fine, your eating within that 8 hour window so its fine! Kyle - Yep, thats what its about, eating in that 8 hour window, regardless of cutting or bulking.

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Posted Thu, 10/25/2012 - 16:36
Andy

Why would you need BCAAs before training , when you fast 16 hours your growth hormone rises so much and you don't get any more catabolic than you would from training after a protein meal or taking BCAAs. I've used protein shakes and aminos and they never helped me at all... The only supplement that actually works is creating, the rest are all a waste of money in my opinion.

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Posted Thu, 10/25/2012 - 15:50
Beast

I have been doing IF the whole year, and I love it; highly recommend it. But I have to point out a huge error : no Berkhan was not the original creator of IF, but of the particular style known as leangains, characterized by quasi-fasted workouts and the 16:8 fasting to eating window ratio.

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Posted Thu, 10/25/2012 - 10:08
Nigel Challenger

Hi, Bob. Thank you for the very interesting article. I have one question, my day starts off training at 5:45AM - 7:00AM and I am home by 7:15AM cooking my meals. Would it be feasible to start the fasting at 8:00AM and end it at 4:00PM?

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Posted Wed, 10/24/2012 - 17:43
Michael

I've tried IF my day looks like this: up at 4:30 am don't eat till 10:30 then eat again at 1:30 train at 3pm eat again at 4:30. Is this ok?

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Posted Wed, 10/24/2012 - 17:07
Kyle

Hey. If I was bulking would I just eat the same amount of calories in an 8 hour window as I would normally throughout the whole day? Thanks

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Posted Wed, 03/13/2013 - 13:31
colt

Hey kyle,
I'm not sure if anyone has replied to you yet so if not then I wil offer what information I know. You were correct. Intermittent fasting for a bulk is the same as regular intermittent fasting, you just have to eat more. take your BMR and add roughly 200 calories to that for a steady, lean bulk. I hope this answers your question.
Sincerely,
Colt