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To Eat Or Not To Eat: Your Fast Guide To Fasting

Intermittent fasting is not just a choice to be miserable; on the contrary, many people find they feel and train better than ever! Here's your intro to the major approaches, and a way to test if it's right for you.

If you spend time wandering around fitness and nutrition websites, you've probably heard some mention of intermittent fasting. The first time, you may have laughed to yourself at the concept. I mean, aren't we all intermittently fasting every time there's not actually food in our mouths? Oh, you. You're so clever.

Dig a little deeper, and it's hard not to be a little intrigued by fasting, if only because the people who love it seem to really love it; and people who don't love it often talk about it like it's unimaginable. The pro-fasters say they feel better than they ever have, and point to a wide range of improved health markers. The opponents scoff. The intensity on both sides is enough to make anybody wonder which side they'd take if they gave it a shot.

But where to start? How do the varieties of fasting systems compare? Won't you, like, starve to death?

Broken down to its bare bones, the most basic premise of intermittent fasting is this: sometimes you eat, sometimes you don't. But you spend more time not eating than eating. Really, that's it. That premise alone may have been enough for you to click the little red x and make this article disappear.

If not, then let's dig deeper into the appeal, risks, and different interpretations of the "eating window."

Why is it So Popular? ///

Perhaps the most important reason behind the increasing popularity of intermittent fasting for both men and women alike is that it's convenient. Think about it: You wake up in the morning and, instead of spending your time in the kitchen, you can make a beeline for the java (or not) and then get straight to work.

There's no food prep, no cleanup, and nothing getting in your way of your productivity. Additionally, many people report (and I personally have found) that being in the fasted state puts them on a high of sorts. They say they feel more energized, more alert, and consequently more able to accomplish things.

Raise your hand if you're a snacker in the p.m. Should be most of you. Now keep your hand up if you frequently find yourself hovering around the kitchen in the evenings, opening and shutting the food cabinets, somehow expecting different snacks to magically appear before your eyes.

Pushing back your feeding window means you can afford to eat more in the evening, when willpower dips to its lowest. Why is this great? It takes a normal weakness and turns it into a huge strength. Really, during your moments of vulnerability, does it make sense to deprive yourself of the things you want? It doesn't have to be that way.

Some people crave simple satiety through treats or wholesome foods. Others yearn specifically for carbohydrates and gravitate toward rice, sweet potatoes, bread, and the like. Still others (such as myself) reach for the gummy bears and desire nothing more than to snuggle up in bed with a bowl of butter pecan ice cream before drifting off.

Intermittent fasting offers you the freedom to deal with your cravings in a finite space, rather than battling them over and over through the day and subsequently amplifying them. Many people find they can still eat what they want, within reason, and stay trim. Under pretty much all systems, you can fall asleep with a full stomach and a shit-eating grin plastered on your face, and you can still nail your macros for the day.

That means you can shed fat without feeling like you're dieting. In general, you will face a whole lot less resistance with your food choices in your day-to-day life.

How Do I Know Which System is for Me? ///

At first glance, you don't. At second glance, you'll realize that one appeals to you a bit more than the others and that you have some reading to do.

I know, you want me to tell you exactly what to do. You want the answers, and of course, the Big Man behind each method will tell you that his way of eating is the best way. But coming from a financially unbiased stance, I can tell you that different approaches will work best for different people. The trick is to find the best one for you.

Here's the CliffsNotes version of five of the most popular current intermittent fasting methods. These are rudimentary summaries, so I encourage you to click around and do your research to learn more about each approach. Each of them also has a different notion of how you should recalibrate or behave during a "break-in" period, so keep that in mind when you research further.

Lean Gains by Martin Berkhan

  • Involves an 16/8 protocol (meaning fast for 16 hours of the day, eat for 8).
  • Macronutrients and overall calories are cycled throughout the week: more carbs and calories on training days, more fats on rest days.
  • Cheesecake and other yummy goods encouraged several times per week in specific windows.

Eat Stop Eat by Brad Pilon

  • Fast for 24 hours once each week; eat regularly the rest of the week.
  • Freedom to eat how and what you want on your feeding days.

Renegade Diet by Jason Ferruggia

  • 16/8 feeding cycle (14/10 for women) with the majority of carbohydrates falling in the evening.
  • Very health-focused: organic, whole foods; though the approved food list is fairly short.

The following two diets are often grouped with intermittent fasting diets, but they can allow for a limited amount of food consumption during the day. As such, you may not spend your day in a "fasted" state, which is generally considered to begin 8-12 hours after your previous meal (hence the word "breakfast").

The Warrior Diet by Ori Hofmekler

  • 20/4 daily feeding cycle: undereat during the daytime, overeat at night.
  • Undereating window can include limited amounts of raw fruits and veggies, poached eggs, yogurt, coffee, and tea.
  • Encourages eating ad libitum from all food groups during the feeding window until full.

Carb Backloading by John Kiefer

  • On Kiefer's 18/6 protocol, you consume protein and fats throughout the day, saving most carbs and calories for the evening after training.
  • Encourages consumption of high glycemic index foods in the post-workout meal, including cherry turnovers, donuts, and pizza.

What to Watch Out For ///

You may look at the above list and feel like one of them has to work for you, but it's possible that none will. Although many of my clients and I have had great experiences with different variations of fasting, I feel obligated to inform you that it is not for everyone.

First and foremost: Fasting isn't just an excuse not to eat. I know women who have reported that the discovery of intermittent fasting has essentially eliminated much of their chronically disordered eating behavior, while others have experienced the opposite, with increased episodes of binge eating, anxiety, and neurosis surrounding food.

On a purely physical level, some of you may just feel like crap, unable to last through the morning hours without doubling over from the sharp pangs of hunger. Others will feel groggy, lethargic, and drained of energy with intermittent fasting. Some will find a way to abuse the rules of intermittent fasting. You may find yourself trying to justify your continued junk food-dominated diet because you've crammed it to an 8-hour window, as if that somehow makes trash more OK to consume (it doesn't). Maybe you'll become more obsessed with food: looking at the clock more often, counting down the seconds until you can break your fast.

If any of the above ends up being the case, then don't try to force yourself into something that doesn't fit. There's nothing wrong with eating smaller, frequent meals spread over the course of the day if that's what works better for you. Neither method is necessarily wrong. What is wrong is either being a slave to your diet, or being totally out of control.

Ready? Not So Fast … ///

Rather than diving headfirst into pure intermittent fasting, I strongly recommend a 2-3 week acclimation period before embarking on any particular system. It's not uncommon to experience some pretty uncomfortable bouts of hunger during the initial stages, so I think it's a good idea to slowly shave down the feeding window rather than jumping from 14 to 8 hours.

So maybe the first week, try cutting your feeding hours from, say, 6 a.m.-8 p.m. to 8 a.m.-8 p.m. That's a 12-hour window you're working with. That seems doable, right? Hunger pangs will be nonexistent at best, mild at worst.

With regard to food choices, eat the same things you've been eating, or depending on which form of intermittent fasting you elect to try, slowly start eliminating certain foods from your diet and replacing them with others. Maybe cut out those breakfast Pop-Tarts, or at least save them for your post-workout meal. You could swap out coconut oil in the place of butter or shortening when you cook. Or you could just add more fish, or fish oil, into your diet.

During week two, you'll take it a step further and eat only from 10 a.m-8 p.m. Think of it simply as a mid-morning breakfast. And dinner is still dinner.

Week three is the final phase of your acclimation period, where you'll have your first 8-hour feeding window. Congratulations, you've just lost your IF-irginity! Cheers all around, and protein drinks on me!

By the end of those three weeks, there's a good chance you'll know whether intermittent fasting (or at least the approach you've chosen to test out) is a good fit for you. There's no better teacher than experience, right?

I know some of you reading this are impatient and eager to plunge into this. You think you're too hardcore to need any sissy acclimation period. If that's the case, then sure, go ahead and jump straight to the 8-hour window. Don't say I didn't warn you, though.

FAQs On Fasting

Q
I'm a shift worker. Can I still practice intermittent fasting?

Technically you can, but if your feeding window changes all the time, it can wreak havoc on your metabolism. It's far from ideal. Work with what you've got, but do your best to eat at approximately the same times every day.

Do I have to count macros while intermittent fasting?

No, you don't. But understand that just because your feeding hours have been reduced doesn't mean that your diet has now become a free-for-all. You will still gain weight if you consistently eat over your maintenance calories, no matter how narrow your feeding window is. Intermittent fasting is pretty neat, but it isn't magic.

What if I miss my window? For example, if my typical feeding times are from 10 a.m.-8 p.m. but one night I don't eat until 10 p.m. Do I adjust my feeding window the next day?

There will invariably be days when this happens, because life gets in the way. The train came late, you were wrestling with your baby, or you flat-out forgot. It happens. Just eat when you can and go back to your normal hours the next day. Don't sweat it. Again, try to be as consistent as possible.

How will intermittent fasting affect my workouts?

You don't necessarily have to change the way you train just because you're intermittent fasting now. Some methods will call for specific ways of training, and if that's the case, then follow the appropriate protocol. Otherwise, keep doing what you're doing in the gym.

What do I do if I train at the butt-crack of dawn?

If you train early in the morning or at any point before your feeding window, then it might be a good idea to sip on some branched-chain amino acids (BCAAs) to keep from feeling depleted while training. Different protocols have different views on this and other supplements, but I've personally found aminos to be helpful. You can then break your fast immediately afterward, or continue the fast with more BCAAs until it's time to chow down.

What would a typical day look like if I trained in the morning?

There are many ways to go about this. But here's just one example, again using BCAAs:

  • 6 a.m.: 10 g BCAAs with water
  • 6:30 a.m.-7:30 a.m.: Training + 10 g BCAAs with water
  • 8:00 a.m.: 10 g BCAAs with water
  • 10 a.m.: Meal 1
  • 2 p.m.: Meal 2
  • 6 p.m.: Meal 3

The timing and macronutrient composition of each meal will inevitably differ based on whichever intermittent fasting protocol you're adhering to, but in general, this works out well for me.

If we're talking about cardio, you probably don't need aminos unless it's going to be high-intensity in nature.

Will my strength plummet?

Actually, plenty of people report that they experience increased performance in the gym. Pretty cool, huh?

I've been doing intermittent fasting and I feel sooo horrible. What can I do?

The whole premise of eating a certain way should be that it makes your diet easier, not harder. If you're really having that bad of a time, don't do it. Plain and simple.


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About The Author

Sohee Lee holds a Bachelor's of Science in Human Biology from Stanford and is a NSCA certified trainer who loves living a fit life and helping others.

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michaelr575

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michaelr575

Ive never paid attention to fasting diets, this article has, however, peaked my interest. I think some research is in order and when I am finished with my current phase of training perhaps I'll venture down the fasting path! Thanks for the good read and opening my eyes to other possibilities!

Aug 29, 2013 7:14pm | report
 
illusionsmichal

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illusionsmichal

I tried the lean gains version of this by Martin Berkhan and loved it. I got stronger than I've ever been the 4th week of my intermittent fastings, and lost 6 lbs at the same time. You do however need to pay attention to your macros contrary to what this article says, especially if you're wanting to keep the strength gains. I did great until vacation and have been meaning to get back on it since. It's also nice not having to worry as much about timing your meals.

Aug 29, 2013 8:53pm | report
 
Ramar23r

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Ramar23r

I dont agree with this at all, it's just a fad diet thats based on simple caloric restriction (ergo why you still need to be on a diet during your eating hours). It not only claims to be a new way to diet, but worse yet it puts a foot in the door for developing eating disorders. **Think of the "if a little bit is good, a lot of bit must be great!" people** I hope bb.com starts posting more content from peer reviewed sources rather than that latest word-of-mouth trends.

Aug 29, 2013 9:00pm | report
 
SugarNation

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SugarNation

Not sure what you mean by "content from peer reviewed sources." Our writers frequently reference peer-reviewed studies where relevant to the subject at hand, but we would never just publish a stand-alone study, peer-reviewed or not. As for intermittent fasting, as the author states: It definitely isn't for everyone.

Aug 29, 2013 10:36pm | report
ShellNico

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ShellNico

Facts- its not a fad diet or trend, it has been around for many many yrs it has just stayed under many peoples radar.
Its can be use for 'dieting/cutting' and bulking. You eat the same macros depending on your goals/needs, just in a shorter window. Hence feeling of being more satiated if you are dieting/cutting as your meals will be bigger.
Like the writer puts it, IF is not for everyone and one should stop or not consider doing it if there are signs of an eating disorder or tendancy towards such.

Aug 29, 2013 11:00pm | report
grizzlyberg

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grizzlyberg

There are a few research papers out there about the benefits but all of them pair IF with caloric restriction so the results are not from IF alone. There are quite a few papers also saying that during Ramadan IF (not eating from sun rise to sunset) mood, oral temperature, and alertness all decrease following that style of eating. Using anecdotal evidence, show me one successful bodybuilder that follows IF. I am with Ramar on this one.

Aug 30, 2013 7:08am | report
SugarNation

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SugarNation

She's not recommending it for competitive bodybuilders, although I know a number of physique/fitness athletes--including our own team athlete, Dr. Sara Solomon--who use it religiously.

Aug 30, 2013 8:07am | report
dwest62

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dwest62

Why don't you all try something before commenting so negatively. I have made excellent fat loss gains pre contest WHILE gaining strength. I can say that never happened while I was eating on a regular basis even with the SAME macros. Also, this is the fitness industry. There are thousands of supplements out there which don't have very many "peer reviews" on them. Do you go around bashing every one of those? This website is supposed to support people. It clearly states it is not for everyone. No wonder bodybuilding is a dying sport. Everyone wants to criticize and bash others.

Aug 30, 2013 11:16am | report
BerserkElite

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BerserkElite

"fad diet" is an ignorant label. If anything is a "fad" its eating 6-8 meals a day for 16-18 hours a day. IF was a great thing for me until my work got in the way. I was happier, more enegetic, and... No way... Thinner. LIES!! actually, I plan on reinstating IF, and changing to 2 meals a day, which, unlike what you "believe", actually helps with eating disorders and insulin control. IF is king. Do your research.

Aug 30, 2013 3:14pm | report
patricktydean24

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patricktydean24

why dont you try it before you say anything bad about it? I use to do the 6-8 meals a day, never having time to enjoy myself cause I was always eating and prepping food, this is the best thing ive ever done, The Renegade Diet is amazing, there is NO and i repeat NO scientific evidence proving frequent meals are better, if anything your digestive system never gets a break, so dont knock it before you try it, and trianing fasted is by far the best way to train

Aug 30, 2013 5:28pm | report
Ramar23r

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Ramar23r

Well seeing that I'm about to graduate from chiropractic school I think I've done slightly more research than needed BerserkBro. To be clear though, I don't care if you do this diet or only other one for that matter. That being said, I could write a novel on why this fad diet is a bad idea, but here's a very very brief explanation. It might be a little dry, but that's usually how real science comes across; (sorry pattydean, I know you like your broscience but you wont find any here). Basically humans are inherently supposed to be in a parasympathetic state (I.e. rest and DIGEST) this is the relaxed state if you will. Counter to that is the sympathetic state, your "flight or fight" response, (think stress). Most will agree that being in a chronically stressed state or rather in an overly stimulated sympathetic mode, isn't a good thing, cortisol levels are elevated, blood pressure stays high etc. Depending on the stimulus (eating, fear, sex, etc), we fluctuate between these two sates, but typically we remain on the parasympathetic side. So why then would you actively push your body to be in a sympathetic state via not eating? This process isn't limited to just the body either, your brain has left and right driven processes as well, and as you can probably guess, one is linked to more stress related activities (right hemisphere) while the other (left) is linked to more logical or unemotional things. So it's not surprising that sympathetic responses are typically generated in the right hemisphere. Over stimulation of these pathways can cause a decrease in the left hemisphere activity and well guess what hormone has the most receptors in the left hemisphere....I'll give you a hint, it's every bodybuilders bff.....give up? It's testosterone! So a down regulation of these receptors will naturally cause less responses elicited from testosterone and from there, in terms of a fitness perspective, **** basically hits the fan. So in short, not eating for prolonged periods of time will not only push you into a sympathetic state, it can actually hurt your overall progress in terms of retention of lean mass as well as cause a slew of medical problems brought on by chronic stress.

-Big biceps are important but being educated is importanter-

Sep 1, 2013 12:24am | report
patricktydean24

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patricktydean24

all were saying is dont hate on something before you even try it yourself, not gonna lie I woulda hated on this a few months back myself but i tried it and it love it, do whatever the **** you wanna do!

Sep 1, 2013 6:56am | report
cgraham531

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cgraham531

Ramar23r I respect you alot for your contribution to this article. Most any topic in the fitness realm is subjective to argument because of the incoming flow of scientific studies presented by it. Here's just a tiny example.. A few years back, my fitness cert. (NASM) had presented studies on static stretching for athletes, stating that it was possibly detrimental in terms of strength if done prior to training/performance. Instead, they recommended either active or dynamic stretching. Just a few weeks ago, NASM released a new study on the subject, stating that it was acceptable to implement static stretching prior to working out, so long as the time did not increase beyond close to 90 seconds. I believe strongly that whatever has always worked for one person, will continue to work, and there is no reason to veer off path. I have tried many different regimens when considering diet. The most stressful was a ketogenic diet mixed with intermittent fasting. However, on days that I fast until after my training, and then backload on carbs, (sort of like a ckg mixed with IF) I feel incredible in the gym when I do this. But never mind my experiences, what I really wanted to touch base on was your theory of sympathetic/parasympathetic modes of the nervous system. It would make sense to me that you would want to excite the sympathetic portion of your autonomic system during your waking hours. Increased adrenaline makes for one hell of a workhorse . Not to mention that we are increasing catabolism (which is what we do when we work out, induce a catabolic state) as well as lypolysis. It would also be paramount to provoke the parasympathetic region of your CNS when you need it most, which would be at night. Increased serotonin production from carbohydrates pair excellent with a great nights rest, which might I add, is also the time that GH is most frequently released. Eating at night makes you fat? I say what a bunch of bourgeois. By all means, most of what I said could be contradicted by anyone who is clever enough, but the last I checked on Layne Norton, he had quoted a study in one of his recent videos stating that in some individuals, RMR during sleep increased slightly. My 2 cents..

Sep 3, 2013 1:11pm | report
jpstanton

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jpstanton

To the guy representing BB.com, please stop holding Sara Solomon out as doctor in this field. She is a F-ing dentist! It really makes you lose all credibility.

Sep 5, 2013 3:21pm | report
Runnacles

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Runnacles

Ramar your blizzard of caveman philosophy shows your quest for acknowledgement. When once again I must reinforce the main point identified by the author. That this IF is not for everyone, and that it is great in examples such as shift working when an individual is working constantly doing physical work (such as my occupation). Therefore I am maintaining a state of fight or whatever nonsense you are talking about. My stress levels and hormones (testosterone) is raised preserving muscle tissue. In my short time frame of rest before my next shift I am in a state of "digest". Therefore I must consuming daily macros with which ever ratios I am following.
Your referencing is terrible and being a chiropractor is far from mammal nutrition. Your ignorance irritated me motivating my reply. I hope you do not preach to too many poor soles that buy your blabber.
Don't quit your day job bro, 1000 ways to skin a cat dumb dumb.

Runnacles out

Mar 9, 2014 4:11am | report
iLiftWeightzz

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iLiftWeightzz

I have always wanted to fast but never knew exactly how to do it since school is kind of the problem.
How could i incorporate Fasting to my School Hours
School starts at 6am and school ends at 2:30am im usually in the weight room at 3:00 and lift until 4:00
i sleep at 10, how would you fat with this time? Example?

Aug 29, 2013 9:18pm | report
 
ShellNico

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ShellNico

Joel if you can, fast til after you have finished your training. Eating widow would be 4-10pm which is still 6hrs to hit all your macros, plenty of time. Before training take some BCAA's as recomended in the article. All the best.

Aug 29, 2013 10:48pm | report
yunusxy

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yunusxy

i have been using fasting like for 4-5 months and i really like it cause i like big meals and i feel amazing i lost fat and gained muscle and get my 6 pack back the good news is u can eat even some junk food in 4 hours eating window and u wont get fat

Aug 29, 2013 10:41pm | report
 
ShellNico

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ShellNico

Nice article Sohee.

Aug 29, 2013 11:01pm | report
 
rjsurp

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rjsurp

I do get a kick when people refer to IF as a "Diet" or even worse, a "Fad diet"; and this couldn't be further from the truth! IF is at essence, in its most simple form an eating schedule; or possibly put; "an easy way to manage your dietary needs", (whatever they might consist of). You can combine IF with a particular diet, which is where some of these other IF versions stem from. But IF is only an "eating Window" or eating period. This isn't a plan for starvation, or depravity!
And on a related note in my personal opinion; I have found that the marriage between IF and the ole' tried and true Macro counting (IIFYM) work really well together. The Eating schedule supplied from IF and the discipline from making sure to meet, but not exceed macro limits and calorie ceilings from counting macros etc works well if you have the time to keep track.

Aug 30, 2013 12:42am | report
 
ShellNico

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ShellNico

Completely agree Roger! I follow IF along with ITFYM and find it so much easier mentally and physically than "clean" eating 6-8 x per day!

Aug 30, 2013 12:56am | report
BerserkElite

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BerserkElite

Agreed. And with IF, most people only need to count 2-3 time instead of 6 . I find this "mental health" friendly. LoL.

Aug 30, 2013 3:18pm | report
xxgameskingxx

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xxgameskingxx

Hugh Jackman (Wolverine) & The Hodgetwins Are Doing The intermittent fasting, And The Results Are Tremendous.
however i heard its great for fat loss but not for building muscle. you will build muscle but its not optimum.

Aug 30, 2013 2:41am | report
 
dwest62

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dwest62

Calories in vs calories out. Simple as that. As the twins say though... Do whatever the f*** you want to do!

Aug 30, 2013 11:19am | report
patricktydean24

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patricktydean24

all about calories man, but like jason ferrguia says in the renegade diet muscle growth happens at such a slow SLOW rate, if you put on a pound of solid muscle each month youre doing great, so no more dirty bulking or getting big fast, just making them lean gainz man, DO WHATEVER THE **** YOU WANNA DO!

Aug 30, 2013 5:31pm | report
Showing 1 - 25 of 68 Comments

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