INTERMITTENT FASTING 101: THE 16/8 DAILY FAST

If you’ve read anything about health and fitness in the past several years, then you’ve likely heard of intermittent fasting.

In a nutshell, intermittent fasting is strategically not eating for certain amounts of time for increased health benefits, more muscle and less fat.

And no, fasting won’t slow your metabolism. Skipping breakfast or any other meal will not force you into “starvation mode.” Those myths have been debunked [1].

Some of the popular fasting protocols include…

Alternate Day Fasting (36 hour fast / 12 hour feed)

Eat Stop Eat (24 hour fast 1 to 2 times per week)

Leangains or 16/8 Daily Fast (16 hour fast / 8 hour feed)

Warrior Diet (20 hour fast / 4 hour feed)

If you’d like more research-based information about the fasting protocols listed above, check out this great article Experiments With Intermittent Fasting by Precision Nutrition.

If you’d like more information about the 16/8 fast and the research behind it, then I highly recommend you check out the Godfather and creator of this approach Martin Berkhan.

I learned quite a lot about fasting through his website Leangains, as well as being a coaching client of his back in the day. I have been and am currently a practitioner of the 16/8 daily fast or leangains method for the last 6+ years.

Since then, I have slightly tweaked this approach with myself and my clients, but the core principles remain.

This article is a no-nonsense actionable guide on how to do the 16/8 method of intermittent fasting.

 

I know this Intermittent Fasting stuff can be overwhelming, so I created a FREE blueprint with printable worksheets to help you get started.

Sign up and get the FREE 16/8 Intermittent Fasting Blueprint when you put your email in the box below:

What is the “16/8” approach to intermittent fasting?

 

This is a method where you fast for 16 hours a day followed by an 8-hour feast (eating) window.

In most cases, this means skipping breakfast, which isn’t hard for many people.

Instead of eating breakfast, many practitioners drink black coffee and lots of water for the first 4-6 hours each day, maybe train, then eat normally for the rest of the day.

Who is it for?

 

  • Those who want an “easier” way to get and stay lean.

I put “easier” in quotes because fasting will work for some people and not for others. But in my experience, for those who take well to fasting, it is an easier way to get and stay lean.

By fasting, you are making it easier to restrict your total caloric intake over the course of each day and the overall weeks and months, which can lead to consistent weight loss and maintenance.

  • Those who like feeling “fuller” instead of constantly being hungry when in a caloric deficit.

Think of it this way, let’s say you’re in a caloric deficit by eating 1800 calories per day with the goal of losing 1lb of body fat per week.

You could split 1800 calories over 12 hours or you could split 1800 calories over 8 hours all while achieving the same goal.

The main difference is that skipping breakfast is only mildly discomforting for most people while evening and late night hunger pangs can be brutal and turn into “binge city.”

Feeling “full” can help stave off eating extra food, binges, and increase overall diet adherence.

  • Those who aren’t hungry in the morning.

This makes it an easy transition to try fasting. You begin your fast the night before. It’s simple. The fast begins after your last meal of the day, you sleep, and then wait a few hours to eat after waking to break the fast.

  • Those who want more mental gains.

More and more research is being done on fasting for potential health benefits including counteracting conditions like Parkinson’s, Alzheimer’s and dementia. Check out this TEDx by Mark Mattson (Professor at Johns Hopkins University and Chief of the Laboratory of Neurosciences at the National Institute on Aging fasting) where he “breaks it down.”

I have personally experienced, along with many of my coaching clients, increased mental focus and productivity while in a fasted state. There’s something about the body not using up energy digesting food in the morning that increases the ability to focus and be productive.

  • Those who want an easier way to manage social situations.

Fasting has it’s benefits when it comes to social situations, mainly being able to stick to your diet if you’re on one and/or not doing too much “damage.”

This could be a party, bbq, date night, etc.

If you know you have an evening social event coming up, one option is to fast all day until your event and then basically eat what you want.

If that sounds impossible to you, another option is to eat one small to moderate sized meal that is high in protein and low in fat (lean meats and veggies) prior to your event and then eat the things you like at your event.

Keep in mind that there is no “magic” to fasting. What truly matters is total caloric intake in alignment with your goals, not when you eat those calories.

Who is it not for?

 

  • Those who have had a history of eating disorders.

  • Pregnant women or women who are considering pregnancy.

Aside from pregnancy where no form of fasting should be practiced, fasting can impact hormone regulation in women to a much greater extent than men.

That is why it is generally recommended that women have a shorter fast (14 hours) than men (16 hours) with this approach to minimize potential hormonal imbalances.

  • Those who function better by having breakfast.

Some people just feel and perform better by eating in the morning. If so, fasting may not be a good option.

  • Those who are bulking.

It is definitely possible to “bulk” and add muscle using the 16/8 fast as I and many others have done it successfully.

But, for those who have trouble eating a lot of food in general and are wanting to gain weight, fasting and having a shortened eating window can make a difficult task of eating in a caloric surplus even harder.

More food and less time to eat it can lead to feeling extremely uncomfortable and lethargic.

An Important Note: Intermittent fasting may not be right for people who have issues with adrenal fatigue, improper thyroid function, blood sugar regulation, hypoglycemia, have diabetes, etc. If you suffer from any of these or have reservations about fasting, consult your doctor or dietitian.

Intermittent Fasting and Women

 

It does seem that men and women have different experiences with intermittent fasting. It is known that restricting food in the form of fasting can cause hormonal imbalances in women.

My best recommendation for women who want to try fasting is to check with your doctor and get some blood work done. Try fasting, listen to your body and get re-checked to decide if fasting is a good choice for you.

If you’re a woman and have read the warnings and recommendations above and still want to try fasting, look out for…

  • Fatigue
  • Depressed mood
  • Bloating
  • Headaches
  • Irregular periods

There’s just not enough research out there done with women and fasting to know all the effects. It’s your choice and you know your body best; just be smart about it.

Women also may try a shorter fast of 14 hours and a larger eating window of 10 hours to combat potential hormonal imbalances.

How to do it?

 

Follow a few simple rules.

  • Fast 16 hours per day.
  • Eat within an 8-hour per day.
  • Exercise with high intensity with weights, a few times per week.
  • Use 10 g of BCAA before or during your exercise session if you’re training fasted (in my opinion this is optional).
  • On training days, eat higher calorie / carb having 2-3 big meals of protein, veggies, and carbs.
  • On non-training days, eat lower calorie / carb having 2-3 meals of protein, veggies, and fats.
  • Eat mostly whole, minimally processed foods, instead of processed foods or supplements.

Here’s a sample weekly summary…

 

 

Here’s a sample single day schedule with midday fasted workout…

 

By the way, the above charts are only a small piece of what I’ve made for you. My 16/8 Intermittent Fasting Blueprint covers everything you need to know to get started right away, daily fasting protocols based on your training schedule (early morning, midday, evening), and printable tracking worksheets.

Get the 16/8 Intermittent Fasting Blueprint for FREE when you sign up for my email list in the box below:

Tips and Strategies

 

  • Drink plenty of water throughout your fast and the rest of your day. This will help keep you hydrated and feeling full.
  • If you tolerate caffeine (black coffee or green tea), have 1-2 cups per day during your fast. Caffeine has a hunger “blunting” effect for many people.
  • If you’re new to daily fasting, give it a good two weeks. Sometimes it just takes the body a little bit of time to adjust to a new routine.
  • If you find this way of eating too strict, try extending your eating window by an hour or two.

Remember, fasting is not a “magic” diet, it’s just a different way to eat your food throughout the day that can help with getting lean and staying lean. No matter if you fast or not, “how much” you’re eating is the ultimate determining factor in weight gain or weight loss.

16/8 Daily Fast FAQ

 

Q: Can I fast on certain days and not fast on others?

A: Sure. There’s no wrong way to do it and you’re not going to “mess” anything up if you do. What matters most is how much you’re eating in relation to your goals, not when you eat.

Q: Can I train more than 3 days per week? Your “weekly” schedule graphic above only shows 3 training days.

A: Yes. I find that 3 strength training days is more than enough for most goals. But if you like training more, no problem.

Q: Do I need to track how much I’m eating, like calories or macronutrients?

A: I do recommend some form of portion control if you have a specific fitness goal (fat loss or muscle gain). I find that being precise with your intake is the fastest way to get there.

Read my guide on How to Track Macros 101 for more info.

Q: What’s the purpose of calorie / carb cycling on training days and rest days?

A: The idea behind this is that eating more on a training day will supply your muscles with enough nutrition to fully recover. And, eating less on rest days when you’re body doesn’t need as much fuel.

For fat loss (caloric deficit), eating more on your training days will negate any muscle loss and eating less on your rest days will help you burn more fat.

For muscle gain (caloric surplus), eating more on your training days will maximize muscle gain while eating less on your rest days will minimize fat gain.

But, the main benefit I see and experience with myself and my clients is that while in a caloric deficit, cycling calories and carbs can ease the feeling of “dieting” everyday and increase overall success.

Q: I’m trying fasting and I’m really struggling with hunger and energy. Am I doing it wrong?

A: No. You’re body is use to being fed at more frequent intervals. Give it a few weeks as you’ll likely adjust pretty quickly. If not, then fasting may not be a good fit.

You can also try shortening your fast and then slowly increase it over the course of a couple weeks.

Q: Can I eat 2, 3, 4, etc. meals during my eating window?

A: Yes. You can eat as many times as you want as long as you keep it within your eating window. In my experience, 2-3 meals is the sweet spot.

Q: Do I have to take BCAA’s if I’m training fasted?

A: No. Taking BCAA’s if you’re training fasted is used as a “muscle insurance policy.” The idea is that you have Branched-Chain Amino Acids (BCAA’s) in your system instead of being completely fasted which would minimize muscle loss.

I like them and take them sometimes.

Q: I’m super full all the time. Help?!

A: This is normal if you’re new to this approach to fasting. Skipping breakfast and having those calories later in the day can definitely increase the feeling of fullness. The body in most cases will quickly adapt. If it doesn’t, then fasting may not be for you.

Q: Do I have to drink black coffee or green tea?

A: No. The idea here is that if you tolerate caffeine, then drinking black coffee or green tea can serve as an appetite suppressant during the fast. Caffeine can also be a great pre-workout boost of energy to make the most out of your workouts.

If you don’t like coffee or tea, you can have anything that has caffeine and calorie free (caffeine pills, energy drinks, etc.)

If you don’t tolerate caffeine well, don’t use it.

Q: Can I put cream and sugar in my coffee or tea?

A: Try to keep it to just black coffee and plain tea which has 0 calories. Cream and sugar contains calories and if you add them, you’re breaking the fast.

Q: If I perform cardio, why is that not considered a training day and I get to eat more calories?

A: Cardio burns calories but is much less taxing on your muscular system and easier to recover from, so the extra calories are not needed.

I’d love to hear from you:

  • What questions do you have about intermittent fasting?
  • Have you tried fasting before? And what methods did you try?
  • Do you have any reservations?
  • Have you had success with fasting for fat loss and/or muscle gain?

Let me know if the comments!

-Aaron

PS: You just read over 2,000 words, and I thank you for that. There’s so much stuff out there pulling for your attention so I truly appreciate you taking the time to read what I’m putting down. If you’ve made it this far, how about going all the way?

I’ve found a lot of people who are new to fasting struggle with knowing when to eat and not eat, how to incorporate training with fasting, and keeping track of their fast and feast windows. So I made the 16/8 Intermittent Fasting Blueprint to address all those challenges and get you started right away.

Sign up in the box below and get it FREE…