In my previous article, The Benefits of Intermittent Fasting, we talked about what this diet is and the benefits. Now I’m going to talk about HOW to actually start IF’ing.

Intermittent Fasting (also called ‘IF’) can help you LOSE weight while retaining muscle (this is called a CUT), gain lean muscle mass while minimizing fat gains (this is called a LEAN BULK), or building muscle while keeping the same level of bodyfat (this is called BODY RECOMP). This article will focus on a CUT style diet which is probably 90% of you folks are most interested in.

At the end of the day, the only difference between these three approaches is the diet aspect which is HOW many calories you eat per day and your daily choice of macro nutrients (protein, fat, and carbs)  that make up your diet.

There are two parts to Intermittent Fasting: The Diet and Weightlifting.

If you just want the diet part, then don’t bother reading. You won’t get proper results if you don’t lift weights WHILE following the IF diet; you’ll get half-assed results and waste your time.

Note for people who train Muay Thai 3 or so times a week, you should have no issues adding Intermittent Fasting to your diet to aid in weight loss goals. If you train a lot though (i.e. you are a fighter), you’ll need to overhaul the IF style diet based on your training habits. I’ll have an introductory guide to Intermittent Fasting for Muay Thai in the future for people who are fighters.

Ok, let’s break down the Intermittent Fasting Diet.

Part 1: The Diet

Intermittent Fasting really focuses on DIET, NOT cardio, to get results. You can get absolutely shredded with little to no cardio based on diet alone.  That’s not to say you can’t combine IF with cardio (I do and have been doing IF while training Muay Thai in Thailand for years now). But, IF (and body transformation) is most effective via diet rather than cardio. Having said that, for the person who’s not doing insane amounts of cardio, you should have no problem doing IF.

Note that for IF, supplements are unnecessary for the most part. The only two I recommend protein power if you can’t eat enough protein (which could be the case) and BCAA’s before training IF you are training in a fasted state.

1. Choose Your Feeding Window

This eatingintermittent fasting feeding window ‘window’ depends on how long you are fasting.

For the best results, you should fast at least 14 hours per day minimum but aim for 16 hours.  That means your feeding window (aka the period of time when you are allowed to eat food) will be between 8 to 10 hours.

So just choose a time during the day you want to start eating. 

Your Feeding Window is up to you. It doesn’t matter WHEN your feeding window starts during the day, just as long as you have a solid 16 hour fasting period BEFORE you break your fast.

You can have your first meal in the afternoon (skipping breakfast) or at night or in the middle of the day. It’s completely up to you — as long as you have 16 hours of fasting beforehand.

The usual template here is to skip breakfast and start eating around 11 AM or 12 PM. Assuming you’ve had your last meal around 7pm or 8pm the previous night, that means if you start eating around 12 PM, that’s a 16 hour fast. Or you can have dinner around 6 PM and have your first ‘meal’ around 10 AM the next day — as long as you are getting that 16 hours of fasting in!

Just make sure you end your eating period the same time every day. So if your feeding window starts at 12 PM, you would have your last meal before 8PM the same day, so you can begin your fast again (and start eating 12 PM the next day again). If you are consistent every day with breaking your fast around the same time (say 12ish) and ending your meal times around the same time (say 8pm ish), your body will adapt to this schedule and you won’t feel hungry outside of these times.

2. Choose How Many Meals a Day You Eat in that Feeding Window

intermittent fasting meals per day

The number of meals per day you eat is completely up to you. You can have one meal a day (you better have a giant appetite to stuff all calories in one go, however), you can have two meals a day (most people do this), you can have three meals a day or more.

So just choose how many meals a day you want to eat. The usual choice here is 2 meals a day (the first the largest).

When you figure how many meals a day you eat, just keep this in mind: By eating LESS meals per day, you can eat MORE calories per meal.

So if you are a person who loves to really go hard when it comes to eating a meal, I recommend you eat less meals per day so you can eat more per meal while still being on a calorie deficit.

The importance thing to take away here is the TOTAL caloric intake per day NOT how many meals your calories are broken into. I personally find eating two meals a day works for me. This means you can have two large meals a day; if you are on a cut, this means you feel a lot more full.

3. Adjust your Calorie Intake

calorie counting intermittent fastingYou adjust your calorie intake per day to meet one of three goals:

  • Lean Bulk (Calorie Surplus)
  • Recommended: Cut (Calorie Deficit)
  • Advanced: Body Recomp (Maintenance or slight caloric cycling of + and – calories depending on workout day)

You are going to do a bit of elbow work figuring out how much of what you need to eat every day. Depending on whether you are bulking or cutting or trying to do a recomp, you’ll need to figure out your calories and macros for a diet plan. I recommend looking at figuring out your macros first. If you have the right macros, your calories will be on target since figuring your macros is basically just a more detailed version of figuring out calories.

If you just SKIP this step and decide to wing it, you are not going to get results. So don’t.

I’ve broken this into four steps for you:

#1. Choose an overall goal here to lose (fat) weight or gain (lean) weight. Personally, I recommend you should go with the CUT to lean down to around 10-12 percent bodyfat to get a ‘good base’, then work from there.

#2. Based on #1, figure out your calories per day needed to achieve #1.

#3. Based on #2, you will then figure out your Macro-nutrient food ratios (protein, carbs, and fat) in grams that you have to eat in order to meet your caloric intake per day #2.

#4. Once you have your macros figured out (you can often figure out your macros first then adjust them to meet your calories. So you can ALSO do #3 first THEN #2 afterwards), you create a daily meal plan, broken into how ever many meals per day you decide to eat.

Must Reads  about putting together your diet here:

4. Keep Protein High Every Day

On weight lifting days, you use leaner cuts of meat (chicken/fish/steak/pork). On rest days you can eat fattier cuts of meat.  Varying between fatty and lean meats ties directly into the next point (#6).


There are a number of reasons why you want a high level of protein:

1) It has a satiety effect (keeps you feeling full)

2) It has a high thermal effect (TEF). This basically means it requires a lot of energy to break it down. This means it’s about 3 calories of energy required per gram of protein digested.

3) It allows protein synthesis (muscle building) when you have enough calories. In a deficit, an abundance of protein may prevent muscle loss.

With LeanGains style of Intermittent Fasting, you should take about 3 grams of protein per kg of total bodyweight. There is some dispute in the fitness community about the level of protein needed. The general consensus is that it’s better to slightly overestimate your protein requirements than underestimate, especially if you are highly active (you lift weights, you train Muay Thai, etc). This is even more so if you are on a calorie deficit, when having more than enough protein around in your body means your body may keep the muscle (you can be sure if you don’t have enough protein, especially if you are on a calorie deficit, you will be losing both fat and muscle). Protein in general has a satiety effect, meaning it keeps you feeling more full — and this can be very beneficial if you are on a calorie deficit.

You should try and get most of your protein from chewable sources (i.e. meat, not powder).  The reason for this is that if you eat lean protein, it has the additional benefit of increasing satiety (helps keep you feeling full) over liquid protein sources. However, you can use protein powder if needed (I do).

5. Cycle Carbs and Fat Intake Amounts on training and rest days

carbs and fat

Since we are keeping protein levels high at all times, we only play around with Carbs and Fat levels from day to day. As stated in #5, you can help meet the FAT levels by cycling the types of protein you eat on lifting. On weight lifting days, you use leaner cuts of meat (chicken/fish/steak/pork). On rest days you can eat fattier cuts of meat. On the days you eat fat, you can also have other fatty foods like cheese, for example.

Why do you cycle carb and fat intakes?

Cycling your carbs and fat intakes on workout and rest days can optimize the results, especially when you start looking at trying to gain muscle while keeping bodyfat around the same (called a body recomposition).  On workout days you keep your fat low and carbs higher on training days is that carbs are less likely to be stored as fat on those days (and carbs refuel your glycogen levels). On rest days you can up your fat level but keep your carb level down (which helps keep insulin sensitivity down, which means your body will be in more of a fat burning state).

You can still get results without micromanaging carbs and fat intake, however, but it’s not really too hard to do this and it’s worth the tiny bit of extra effort.

On Training days, eat more carbs and less fat

On Rest days, eat less carbs and more fat

Again, the idea here is you basically take advantage of some metabolic tricks enabled by specific meal timing by varying up your macronutrients on weight lifting days and non-weight lifting days. We can get all technical and give the exact science for the WHY, but it’s beyond the depth I want to get into here. If you eat more carbs when you work out and less on resting days, you should be good.

6. Cycle Calorie Levels on training days and rest days (OPTIONAL)

If there is a ‘complicated’ part of Intermittent Fasting, this would be it.  This is more of an advanced topic. So most of you can skip it if you are just straight trying to lose weight.

If you are new to dieting, again skip this because you are just going to get confused. Just keep your calories at a deficit every day.

For those who are interested, I’ll give some short details here.

Basically, Calorie Cycling applies mostly to the LEAN BULK or BODY RECOMP diet.  The idea here is to basically feed your body a slight calorie surplus on workout days and on rest days, keep calorie at a deficit or near maintenance. This provides a short-term boost of calories on days when your body needs it, giving your body the nutrients needed for protein synthesis (muscle building).

On your rest days, you are at a calorie deficit to burn the fat. Many people find this sort of calorie cycling beneficial and can potentially lead to better lean gains (i.e. gaining muscle with less fat or nearly no fat at all). Combined with the next section (Cycling Macros), you are basically tricking out your body for optimal muscle gains with minimal fat gains.

  • Your weekly calorie count, if you are on a CUT, will still be at a deficit level.
  • Your weekly calorie count if you are on a LEAN BULK will be positive.
  • Your weekly calorie count if you are on a BODY RECOMP will be roughly maintenance or slightly over.

I’ve personally been on a BODY RECOMP style diet/workout for close to a year and have gained several kilos of muscle with no fat.

There are three possibilities for your calorie consumption every day.:

  • a calorie surplus (+)
  • calorie maintenance (0)
  • a calorie deficit (-)

The variance in calories depends if you are reducing or increasing 15%, 20%, or 30% your daily calories in relation to your maintenance level. so 20% would be 20 percent of your daily required calories for body weight maintenance. If your maintenance is 2000 calories, that means 400 calories, either + or -.

If you are on a pure CUT diet, you would keep workout days at all (-) or a mix of (-) and (0). Assuming you lift 3x a week, Monday, Wednesday, and Friday:

Monday (0) Tuesday (-) Wednesday (0) Thursday (-) Friday (0) Saturday (-) Sunday (-)

If you were trying to do gain muscle and lose fat at the same time, you might look at a combination of (+), (-1), and (0)

Monday (+) Tuesday (0) Wednesday (+) Thursday (0) Friday (+) Saturday (0) Sunday (0)

7. Weight Train 2x-4x a Week. Rest the Rest.

It’s critical to lift weights while doing an IF style diet. If you don’t plan to lift, then don’t your waste time with IF. See the next section for the training breakdown.

Part 2: The Training


It’s very important that you lift weights. If you want to get ripped you need two things: 1) low body fat and 2) enough muscle mass.

The whole goal with IF is to either 1) cut fat while maintaining current muscle, 2) gain lean muscle while minimizing fat gains, 3) gain muscle while keeping fat around the same.  You can’t do ANY of these effectively on diet alone. If you JUST use diet and refuse to lift, you’ll lose weight, but that weight will be fat and muscle – you’ll just end up a skinnier version of yourself with little muscle definition.

There is a lot of benefits to be had by combining by lifting weights during your FASTED state (this is unique to IF out of any other diet program). If you are are following the LEANGAINS version of IF (which I do), you also ingest BCAA’s before your (fasted) workout. Both of these strategies  (working out fasted and ingesting BCAA’s before the workout) help to FULLY take advantage of the hormonal boost you get from the fasted state when it comes to building muscle.

These hormonal boosts *can* mean:

  • you keep more muscle  while on a calorie deficit
  • lean muscle gains with little fat gain while on a calorie surplus
  • slow muscle gain with no fat gain while on a maintenance level of calories

It’s not necessary to lift weights in a fasted state, but given the potential benefits, there is no reason why you should not. Again, you will still get results if you work out AFTER you’ve eaten, so it’s up to you.

1. Strength Train 2-4x a week


The goal with IF is to improve your body. And to make that happen effectively, you are going to have to lift weights. IF you don’t want to lift weights then just stop reading here – you won’t get the same results.

You don’t have to lift 4-6 days a week, for hours a day, to see results. There is a lot of flexibility here for how many days a week you lift, the specific days you choose to lift, and the type of lifts you do, and the programming breakdown (the volume of lifts you do per session, broken into sets and reps).

You can radically transform your body over time with just 2-3x a week in the gym, for less than 45 minutes a day.

Use the following key points to guide your Weight Lifting Protocol:

  1. Lift 3-4x a week if you don’t do a lot of cardio. 2x if you are involved in a serious sport where you train 4-6x a week.
  2. Focus on compound movements that utilize barbells.  Compound movements that will maximally stimulate your muscles, especially if you are a beginner
  3. Apply the principal of progress overload by increasing weights (if possible) every week. This will force your muscles to become stronger. The end result is more muscles, more strength, and a better body.
  4. You only need to lift anywhere from 30 minutes to 1 hour per session. Anymore than this is unnecessary, especially if you are new to lifting weights.
  5. Training times are up to you, though for the best results with Intermittent Fasting, train fasted. You can opt to train in an unfasted state if you can’t train fasted. The important thing is that you TRAIN.

There are a number of proven ‘Weight Lifting Routines’ for beginners that have been proven over and over again to work.  All of these programs focus on compound movements and heavy lifts and progressive overload (steps 1-4),  These are especially optimal for building as much muscle mass as possible which is the goal here or to keeping muscle mass as you cut calories.

There are a number of that put everything together for you

Read my Strength Training 101 for a full guide on how to strength train with a routine.

A note about cardio. Cardio is generally not recommended if you are trying to maximize strength and muscle gains, however, as this is a Muay Thai website and most of the readers are Nak Muay, I realize this is not practical. I have found you can combine strength training and muay thai quite easily, though you have to modify your programming.

Read How To Strength Train with Muay Thai to find out how.

2. Ingest 10-15 grams of BCAA’s 10 minutes before You Lift

The LeanGains style of IF has you take BCAA’s in the morning right before your workouts IF you lift weights fasted. I have been doing this and I feel it offers a lot of benefits. Don’t bother though if you lift weights when you don’t fast.

The Final Word on Intermittent Fasting

I’ve given a pretty thorough breakdown on HOW to go about intermittent fasting. If you want to lose weight and completely transform your body, IF can work wonders. At the end of the day though, you still have to put in the work.

I’ve talked about Intermittent Fasting in general. If there is some interest in the comments, I may write an intro on how to combine Intermittent Fasting with (heavy) Muay Thai training (due to the heavy cardio, you need to modify the strength training volume and diet slightly).

Intermittent Fasting is a great way to quickly lose weight while training Muay Thai if your goal is to lose weight and get ripped. I’ve also found that Intermittent Fasting is a  good means to keep ultra lean, which if you are a fighter means you don’t have to cut (as much or any) weight when you fight. So there are some huge advantages if you combine Intermittent Fasting with Muay Thai.