One very popular IF methodology that’s linked to in this article is Leangains: An I.F. based diet and training program that’s the brainchild of Martin Berkhan.
The diet has rapidly increased in popularity within the last few years, and is now by far the most used fasting based bodybuilding program. Despite its current popularity, it is also often misunderstood and done incorrectly. Most articles that write about how to “do” it lack the necessary specifics that you need to know to get started.
I’ve personally been doing it for over 4 years now, and it’s my go to method for easy fat loss when I need it. When I started out years ago, I had a lot of unanswered questions that I had to figure out by consulting various resources and with my own trial and error. I decided to publish a step by step guide that covers everything you need to know to properly use the program to effectively lose fat, and I’m going to summarize it here.
Step 1: Body composition improvement programs have one of these three goals:
Fat Loss: a “cut” — lose as much body fat as you can while maintaining your lean muscle mass.
Lean Mass/Strength Increase: a “bulk” — gain as much strength and muscle mass as you can while limiting fat gain as much as possible.
Gradual Recomposition: a “recomp” — slowly improve your lean muscle mass to fat ratio over time.
To do things properly, you must pick one of these goals. Most people start with a cut because they want to lose fat, so that’s what we’re going to explain how to set up step by step.
The defining trait of an I.F. diet plan is that you incorporate a daily 14-18 hour fast. The main benefit of fasting is that it makes hunger control way easier. At least for me. Though, fasting in general can potentially reap a number of physiological benefits. It doesn’t matter when your feeding and fasting windows are. Just do what’s most comfortable for you. I typically eat between 12 pm and 8 pm (for example).
Step 2: Figure Out Your Calorie and Macronutrient Requirements
The idea is to eat at a weekly caloric deficit of 15-20 % over time until your ideal body fat level is achieved. To do this, calculate your calorie requirement using an online calculator. For now, assume that you’ll be training 3 times per week when you fill it out.
For an example, I’ll show my figures from my most recent cut:
Starting weight: 79kg
Ending weight: 72.5 kg
If I put my figures into the calculator using the athlete formula and 3x/week of exercise, my total daily energy expenditure (TDEE) is 2250 calories. Therefore if I want to lose fat and eat at a ~15-20 % caloric deficit my daily average caloric intake should be 1800/day.
Next, figure out your daily protein, fat, carbohydrate, and fiber requirements using these guidelines:
Protein: 1-1.5 g per lb (0.45 kg) of body weight per day
Fat: 0.25g – 0.3 g per lb of body weight per day
Fiber: At least 0.2 g per lb of body weight per day
Carbohydrates: All remaining calories in your daily caloric budget.
Here were my targets on my most recent cut:
Protein: 180-200 g/day
Fat: 50-60 g/day
Carbs: 75-100 g/day (off day) or 225-300g (training day)
Protein and fat intake should stay fairly constant on a day to day basis, but you’ll be eating much more calories in the form of carbs on training days than you will on off days, which I explain in the next step.
Step 3: Figure Out Your “Split”
A popular dieting method is a deficit/refeed carb cycling style that can be particularly effective for maximizing fat loss. The idea is that you’ll eat at TDEE “maintenance” on training days (2-3 times per week) and you’ll eat at about a 35 % deficit on off days. This comes out to a 20 % weekly deficit on average. The difference between your caloric intake on training days and off days is what we call the “split.”
Here are my training/rest day targets during my cut:
Training Days (Mon, Wed, Fri): 2250 calories; ~180 g protein, ~60 g fat, ~250 g carbs
Rest Days (Tue, Thu, Sat, Sun): 1550 calories; ~180 g protein, ~60 g fat, ~75 g carbs
This comes to a daily average of 1800 calories a day over time.
An important note: Your split and macros are not set in stone. For example, some people do better with higher fat and lower carbs. Or, some people do better with a smaller split and prefer to eat more calories on off days and take some of their deficit on training days. The key is that you hit that weekly 15-20 % deficit one way or another. As long as you do that, you’ll lose fat, and a little flexibility here and there is totally fine. If you’re protein is a little low one day or your fat is a little high one day it’s not that big of a deal.
Step 4: Figure Out Your Meal Plan
When people hear the phrase “calorie counting” they often cringe, but it’s actually really simple and easy to do if you set up your diet and routine right. The best thing to do is to pick one meal plan for off days and one meal plan for training days and cycle those two daily meal plans over and over. Doing it this way you know exactly what to cook when, you know exactly what you need to get on your weekly grocery run, and you’ll know you’ll hit your calorie and macro targets every time.
It might sound a little boring, but the important thing is that it’s easy and it works. Start with just the two meal plans for the first few weeks to get the ball rolling, and then you can add in a new recipe from time to time if you want more variety.
Step 5: Figure Out Your Training Program
Leangains calls for heavy weight training 2-3 times per week with little to no other exercise. The idea is that while on a cut you only want to do the minimally required training to maintain your strength and muscle. You also want avoid over training while in a calorie deprived state. Plenty of people do gain strength while cutting for fat loss, though, especially beginners and/or people who are significantly overweight.
Step 6: FAQ
Can I have occasional cheat meals?
Yes! Absolutely. That’s why intermittent fasting is so great: You can “save up” a ton of calories for a restaurant meal, go nuts occasionally, and not completely derail your progress.
What should I eat?
Eat what you like as long as you hit your macros and calorie requirements. Use common sense: just because you can hit your macros with pizza and ice cream doesn’t mean it’s ok to only eat that stuff.
Should I train in a fasted or fed state?
This is a matter of personal preference. Some people swear by fasted training, while others can’t stand it stating it makes them feel flat and drained. There are potential benefits and downsides to either way. Do what works best for you. If you do train fasted, Martin recommends BCAA supplementation.
How fast can I lose fat?
Most people can lose 1+ pounds of fat a week up until they start to get really lean. You can probably get your desired results in 4 months or less.
Can I do other additional training?
Yes, you can. Just adjust your caloric targets accordingly to accommodate increased activity. Do know that excessive cardio is discouraged while on a Leangains cut because it can be catabolic.
Is this diet appropriate for everyone?
No, definitely not. I don’t recommend that skinny hard gainers do it or any other intermittent fasting program. If you’re a hard gainer, just focus on training hard and eating enough food. Fasting is great for easily reducing caloric intake, but some people end up just not eating enough.
Leangains.com – Blog of program creator Martin Berkhan.
Reddit.com/r/leangains – A community of practitioners. Great place to get help and ask questions.
Cronometer.com – My calorie counting app of choice.