A handbook on The Bulking Diet

Everything a beginner should know about calories to build muscle

The simple, yet powerful truth about calories and how to use them without destroying your appetite all the time
Est Read: 15 minutes
Evidence Based

Workout program being equal, they're what makes The difference between you losing weight or being able to build muscle week after week.

If you want to guarantee that you build muscle week after week, then this is a must.

Let's get started.

Most articles out there about calories are for people who want to lose weight.

This is the complete opposite.

Calories usually need very little introduction, but sadly due to a bunch of misinformation from the media (and The odd personal trainers), they're often misunderstood.

Not to mention the usual bulking advice is designed for guys who have decent genetics, not for guys who struggle to build muscle or beginners that are new to bulking and gaining weight.

Things are either too dumbed down or written for bodybuilders and guys who just need to eat a few more calories, and they'll be building slabs of muscle in no time.

If you're here, that's likely not you.

What are calories?

Since the 1800s a calorie is what we have used to describe the energy content of food. (study)

But things have changed since then. Research has shown that this energy is the primary factor in long-term changes in body composition (and weight).

Geek talk

A calorie is defined as the amount of heat energy that's needed to raise the temperature of one gram of water by 1°C. You'll find calories listed as kilocalories or kcals, but we tend to say calories, to avoid awkward conversations.

They're used to measure how much energy might be in our food or beverages, or released through energy expenditure (or excretion).

They're used to measure how much energy might be in our food (and beverages) or released through energy expenditure (or excretion).

"Calories are directly measured in food by burning the food in a bomb calorimeter, and they're directly measured in humans by measuring how much heat we expel."

- Eric Helms, Stronger by science

Okay, science aside...

They're the energy that foods have. Enough of it and we'll grow, too little and we'll shrink. Of course, there's much more to it than that, as we'll get into…

Why are calories important for our diet?

They're the biggest factor when it comes to deciding if you're likely to change how your body looks and with that, a factor that plays into improving your health.

Of course your workout plays a huge role too, and without it, you're unlikely to have your calories help fuel a muscular body.

But without calories, unless you're gifted with greek god genetics, you're unlikely to add lean muscle to your frame and get the strong, powerful physique you might be after. It's that simple. And the science proves it (study, study)

But it goes beyond merely just needing calories to build muscle…

We need calories just to function:

  • They give us the energy we need for breathing
  • For keeping our heart beating and you know, staying alive
  • Repairing our cells from damage and turnover
  • Are even being used when we're simply just Netflix and chilling

However, when it comes down to it, it's about energy balance.

Energy Balance 101: Calories in vs calories out

As mentioned, calories are pretty much energy. 

And this is where energy balance becomes essential. 

Three things happen with our calories and energy balance:

1. We take in energy in the form of food and calories. We also retrieve previously-stored energy from fat tissue (in the form of fat loss) or muscle tissue.

2. To stay alive, we expend energy. As I said, this happens regardless of what you're doing. If you're just sitting, running or walking, you're using up your energy just to function. This is our Resting Energy Expenditure (REE). 

We also created a calorific expenditure through the thermic effect of food ( calories your body expends digesting, absorbing, and metabolising food) and the activity energy expenditure, through, well you know, movement (like exercise, or even fidgeting - which is common with skinny guys).

3. The balance of energy in and energy out. The created energy balance is often what we're talking about when we speak of getting in enough, or smaller amounts of calories to build muscle or lose fat.

The three categories of calories and energy balance:

Caloric Deficit: If you have fewer calories than your body needs to support its essential functions, it puts your body into a calorie deficit. Doing this for an extended period leads to weight, and fat loss.

Caloric Maintenance: This is when things are all even. You're at a baseline of staying still and maintaining your current body weight. This means that your energy in and energy out are both even.

Caloric Surplus: Here is where we want to be, to build muscle. This is when you're consuming more calories than your body needs for its basic functions.

It's this relationship between energy balance that we need to pay attention to when creating our macro-based means plan.

Factors that influence “energy in”
Appetite - Influenced by hormones that regulate
appetite and satiety
Food consumed - Influenced by availability, palatability, energy density, sleep quality, education, socioeconomic status, culture
Calories absorbed -  Influenced by macronutrient intake, food prep, age, microbiome, health, energy status
Psychological factors - Influenced by stress levels, mindset, perceived control, self-esteem, sleep quality
Factors that influence “energy in”
Energy burned at rest - Influenced by body size, hormones, dieting history, genetic factors, health, sleep quality, age
Energy burned through exercise -
Influenced by exercise ability, intensity,
duration, frequency, and environment,
as well as hormones and sleep quality
Energy burned through non-exercise activity - 
Influenced by health, energy status, stress,
hormones, occupation, leisure activities,
genetic factors
Energy burned by metabolizing food -
Influenced by macronutrient makeup and how
processed the food is
Precision Nutrition Level 1 Certification (Source)

The problem with calories in, calories out

This is a topic of major debate:

We've typically got two polarising frames of belief:

One group believes "this is the only way", they're the kind of people who see calories in, and calories out as the only way of determining if someone's weight goes up or down. Thinking If you aren't gaining weight, or losing weight, just you just need to eat more, or less (and move more). If someone is struggling to gain or lose weight, the answer is pretty simple to them - adjust your calories or move more.

And then there's the other group, who believe that hormones and other issues (like thyroid problems, insulin resistance and metabolic issues) are a reason progress isn't always made when following and calories in and out (shake it all about) approach.

But there's so much more to it:

A balanced approach where both types of people are right.

Let's enter that world for a minute.

*steps into a progressive future*

Not everything is black and white with nutrition.

What works for someone might not work for another.

This is why I'm often sick of everyone telling people to follow a particular diet style (like IF or Paleo). It doesn't take into account real people and real life.

I like how John Berardi puts it:

'Imperative to this, and often overlooked, is your brain. It's constantly monitoring and controlling CICO. Think of it as mission control, sending and receiving messages that involve your gut, hormones, organs, muscles, bones, fat cells, external stimuli (and more), to help balance "energy in" and "energy out."

- John Berardi, PhD, CSCS

Yet, much like everything with this incredible body of yours, the energy balance doesn't demonstrate this well on a graph:

This doesn't take into account the complexities of exercise, stress, appetite, to name a few things.

Which is why most people use calculators that are meant to take these ideas into account. But really, even the best ones are just estimating things, and aren't 100% accurate for everyone.

That's not to say, we're not a fan of calorie and macro calculators. We have one built into the system inside of S2SF. However, like anything in life, pivoting might be needed

They don't bear in mind things like:

  • How often you might fidget
  • How frequently you walk to work, chase your kids, or even just stay at home
  • Injuries you might have that keep you from moving
  • If we absorb all the calories from our foods
  • And a bunch more things

And then there's the fact that food labels can be off (study). So even if your calories are 100% correctly estimated, what you're consuming might not always be.

Let's take a look at some reasons why people might not hitting their target weights when following a CICO approach:

There's a tonne of reasons why people might be struggling.

Here are some of the common issues people face:

"I'm eating 5000 calories a day, and I'm still not gaining weight."

First up, damn that's a lot of food.

And secondly, not to call you a liar, but I'm sceptical of that number.

The reality is, most people are pretty bad at guessing how many calories are in certain foods (study). Grossly misestimating how many calories they're consuming (sometimes up to 50%).

One day you might be eating to your maximum, 6-meals, loads of shakes, bloated more than Santa on boxing day.

The next day, you might be busy, frantically downing coffee and only have two meals.

You'd remember the first day, but due to being busy, likely won't remember eating (or the lack of eating) on the second day.

So, although you think you've eaten a consistent surplus, you're far from it. 

Without tracking calories, at-least in the early days (before you have a baseline of what you're attempting to hit looks like) it's more likely than not, that you're pretty far off what you think you're consuming.

That's not to say it's not possible to hit your calories without tracking everything, but if you're convinced you're drastically over your calorie surplus number and still aren't gaining weight, then you might want to track things.

"My hormones are affecting my ability to reach my goals".

This is an interesting one.

Although hormones can have an effect on our body composition, they aren't the direct cause.

In fact:

They're usually just messing with our energy balance (how many calories we are burning or keeping). They aren't responsible for why we aren't losing or gaining weight, that still comes down to calories.

What exactly do I mean?

They affect how many calories you're burning, or in our case on a bulking diet, not burning. Research shows that people with cases of hypothyroidism, metabolic slow down of 140 to 360 calories a day could occur (study).

Although hormones like leptin and ghrelin are often linked to impacting weight-loss, they're more responsible for affecting hunger, thus affecting how likely you are to under, or overeat (vs directly affecting weight loss) (study).

So although hormones do have an impact on certain factors, they don't directly remove the effects of CICO. This is a great thing, as it means we can work around them to make sure we're still consuming enough calories to gain muscle.

"I've been eating the same thing, and was gaining weight, but suddenly I'm starting to lose weight".

As you probably guessed by this point.

Not everything is as it seems.

This is likely to due to a few things:

  • Your mood has changed (maybe things have you down, stressed or busy). In situations like this, some overeat and some under-eat.
  • Due to physiological changes, Affected by medication, you might be burning fewer calories or doing less exercise.
  • Dramatic changes to sleep quality and/or quantity can cause issues with your hormones and appetite. This could also lead to less than stellar performance in the gym and could also cause you to fidget or be more irritable (leading to calories being burned) (study)

All of these on paper are legit reasons and worries as to why people believe calories in vs calories out isn't as simple as we're told.

And as you can see, many things play a part in the CICO equation. However it all does come down to the fact that calories do matter, and in order to grow you need enough of them.

Is a calorie, really just a calorie?

It's true that all calories have the same amount of energy. One calorie contains 4,184 Joules of energy, which in that respect means a calorie is a calorie.

And sure they're incredibly important (without getting enough you don't stand much of a chance). However, there are a few reasons why it isn't as simple as calories in - calories out. That's because not all calories are created equal.

1. Not all foods contain the same sources of macros

Macros are split into three camps - protein, carbs and fats. Add these together, and you get a calorie overview.

One carb source doesn't give you the same result as another carb source, although they are intact with the same calories and macro unit.

An example of this is glucose vs fructose.

Gram for gram, the two provide the same number of calories as one another. However, they are metabolised in the body in entirely different ways (study).

Glucose has been proven to increase hormones that lead to feeling more hungry (study), lead to a reduction in fullness and overall fat gain, insulin resistance, and other issues.(study)

Fructose, on the other hand, doesn't have anywhere near as many problems. Yet both are the exact same on a label.

Is fructose bad? It depends on your goals, body type and how much of you have. That's not the point of this article (I talk about that more here).

Thermic effect of food

Much like the last point, certain foods have benefits, such as being thermic (aka help burn calories).

This is because certain macros go through different metabolic pathways, and some of these are more efficient than others.

Think of it like this:

There are two roads.

One road is empty, it's got no bends and you can drive as fast as you like without any issues. Another road, however, is dark, full of obstacles and has plenty of bends. They both lead to the same place and have the same distance to go, but one takes much longer to get there.

That's the same with certain macros.

The pathway for protein is less efficient than the pathways for carbs and fat. This means it takes protein longer to reach the end, burning more fuel along the way.

Each macro has its own thermic effect (study):

  • Fat: 2–3%
  • Carbs: 6–8%
  • Protein: 25–30%

Although this does differ from study to study, the consistent point is protein has the biggest thermogenic effect on the body.

Meaning the more protein we eat, the more calories we burn.

Energy levels and feeling full

This is the biggest reason for me, and it's the #1 reason why I don't believe skinny guys should binge eat in order just to get bigger.

The consensus is that as a skinny guy, you can eat anything, and it doesn't affect you physically. You still stay lean and can build an impressive body by stacking carbs on carbs.

However, to me, nutrition goes beyond getting fat or your physical appearance.

As the headline suggests, it's about how you feel with your energy, and how full (or not full) you feel, which if you're anything like I am, is never great when you're hangry.

Eating shitty food, is a great way to make yourself feel shitty, and there's a bunch of reasons for that:

A - The Glycemic Index

This is most commonly spoken about when it comes to carbs, and usually, simply put slow-digesting carbs and fast-digesting carbs.

Fast-digesting carbohydrates (refined) tend to be low in fibre, and are digested and absorbed quickly. This leads to rapid spikes in blood sugar, which means they have a high glycemic index (GI), which is a measure of how quickly foods raise blood sugar.

When you eat a food that spikes blood sugar fast, it tends to lead to a crash in blood sugar a few hours later. Which is why you usually experience the need to have a nap after a meal (for most people after lunchtime at work).

This usually leads to wanting to eat more refined carbs (junk food) which has proven time and time again (study) to lead to excessive weight gain.

Although this on first glance, might not seem to apply to skinny guys, when you look at the effects caused such as brain fog, drop in energy and a greater risk of becoming obese and diabetic (study) you can see why the source of a calorie has different effects on energy levels.

B - The Satiety Index

This is about the effect that certain foods have on your ability to be full (study)

Bony To Beastly - How to eat more calories

Certain foods, like those with fibre, will keep you fuller for longer, than those with little nutrients and no fibre. This means they're also much easier to overeat.

For most people, this isn't good, but for skinny guys who typically have a weak appetite, the satiety index is your best friend. It means you can choose foods that'll allow you to have more calories, vs foods that fill you up fast, all of this taking up the same amount of calories.

An example of this is able to go to town and have 500 calories of doughnuts and still feel hungry, yet it would require force-feeding to have 500 calories worth of broccoli.

I recommend a hybrid approach:

You'll want to focus on getting in whole foods, with a GI index/satiety index that allows you to get close to hitting your macros and still getting in fibre and foods that are somewhat filling, in order to minimise fat-gain.

Not only that but huge importance should be placed on eating foods that are filling, and low GI-index when possible. Bear in mind how the food sources that make up your calories impact your energy, brain fog, muscle retention and fullness, instead of just how to hit calories and macros in isolation or even worse, being hungry all the time, just to hit them goals.

Calories = Macros = Total

Calories and macronutrients work hand in hand.

How many calories a food has, depends on the macros that it's built upon.

What are macronutrients?

From the ancient Greek makros, or "large" — are large, diverse families of molecules that make up the food we eat, and which we can divide into three main groups:

1. Proteins - 4 calories per gram

2. Carbohydrates - 4 calories per gram

3. Fats. - 9 calories per gram

Each of these macronutrients contains energy which adds up to become calories, when they're combined together.

And that's something to bear in mind:

Foods are a mix of macronutrients, and subtypes of macronutrients (steak might contain fat and protein together, with traces of carbs), and depending on the food, the macros might have different types of a sub-set of macros (simple and complex carbs, saturated and unsaturated fats).

Macronutrient based ratios

If you're trying to change body composition, then you're most likely learning about macronutrient ratios.

This is where IIFYM (if it fits your macros) is popular, however, macro based ratios aren't new.

We generally express this in terms of percentages. For instance, a typical "balanced" or mixed meal might include:

• 30% of total energy coming from protein;

• 40% from carbohydrates; and

• 30% from fat.

Enough of these, at the right times and with the right foods (as we'll cover) you'll be consuming enough calories and building muscle consistently.

Changing the macronutrient ratio will change our physiological outcome.

Eating different amounts of protein, carbohydrates, and fats will have different effects in our bodies.

How many calories should you have?

The standard recommended calories for men is 2500, however, for most guys wanting to build muscle, that's pretty far under what you need to build muscle.

If you're just starting out, then you're probably confused by how many calories you need to have right now.

So how do you work out how many calories you need to gain weight?

Well, you've got two options depending on the type of person you are:

  1. Take your current diet and start to add calories on top
  2. Start from scratch and build a flawless(ish) diet plan

Neither of these is better than the other, however most people tend to pick a lane.

Take your current diet and start to add calories on top

We've found through coaching guys that struggle to Gain weight, that something as simple as adding an extra 500 calories to their current diet, can sometimes be enough to get them on the path to building muscle (study).

But that's not the only reason why I recommend doing it.

It makes your chances of sticking with things and getting success greater.

If you're building on top of your current habits, and not having to completely overhaul your diet, then things will be easier.

For this to work, a few things need to be in place:

  1. Your diet shouldn't be completely abandoning the idea of macros and eating foods that aren't pure junk food (sure you guessed this by now)
  2. You have a consistent schedule with what you eat and how often you eat.

Now, this might seem like quite a few things to get right, though, the main one here is #2. That's because it's the one that seems to trip most people up.

If you have breakfast before work, lunch during work and dinner with your family, then it's safe to say that this pattern won't change. That way, you know things aren't going down and up between the days. You have a set rate of calories that stays the same and is traceable, without actually tracking things daily.

If you're someone who finds time slips him by, maybe eats a snack between lunch and dinner, causing you to be too full for a big dinner, then this approach isn't going to work. Although you'll be eating a snack, which could bump your calories up, you'll be missing out on your bigger dinner, and who's to say you wouldn't forget which day you ate the snack, and then skip eating it another day.

In the early stages, this isn't a massive deal-breaker.

If you've got the time to build up 300-500 calories each week, then you'll get results, no matter where you're starting. 

However, if you're someone who follows things to the letter and want results a bit faster, then this next approach might be right for you...

Calories built around a plan

If you're starting, diet isn't muscle-building friendly (built on macros that work) or you struggle to stay consistent, then this approach will be a good one for you.

You'll be able to build a body from scratch and stand the best chance of everything inside of it, being of good use for you.

This one is simple:

You want to start by working out how many calories you need to maintain your current body weight and then build a plan that uses macro ratios that help you build muscle (aka more protein, higher carbs from sustainable sources etc.) - this is different as you'll have a clear plan on what you're actually eating and if it's closer to your ideal calories/macro goals vs winging it and adding calories over time until you reach that ideal ratio.

Your Maintenance Rate:

A good starting point is your bodyweight in lbs x 18 if you're mildly active (walking at work, public transport etc.).

Then tweak from there:

  • If you're stuck in an office for hours at a time and don't move, lower it to 16 or 17.
  • For every extra hour of intense exercise during the week (on top of your bulking workouts—add an extra 1 to the multiplier).

Use this number as a starting point. This article is designed for many different kinds of people, with different metabolisms and features (that's why we cover it in more detail here)

This should hopefully get you near what you're currently eating. If it feels too far under, adjust the numbers and bring them up. If you're not losing weight weekly, then you should be pretty close to this figure.

The next step is to increase your calories in a strategic way, through methods that aren't too tough to follow (aka adding an extra breakfast 2 hours after breakfast) and don't fill you up so much that you want to puke or not follow the plan.

This can be through The Strongman Shake (liquid calories are much easier to have) or through adding a 250 calorie snack, like a flapjack.

No matter the plan, this matters...

If you follow option 1 or 2, the main principle to have in mind, like many areas of life is measuring and adjusting.

If after your first week or two on a bulking diet, your weight hasn't increased much, don't worry, that's common, but if it continues then things need to change:

  • You'll want to increase your calories by 200-300 again. This should make up for the dip you might be experiencing
  • Markdown on a sheet when you have each meal. Increasing your consistency with meals is a surefire way to get results (this is something that was needed a lot in Precision Nutrition)
  • Test how much your weight increases over a longer period and make sure to have realistic goals in mind

The Superhuman Lab Summary

Next to a great workout program, how many calories you have will determine how fast, or slow you gain muscle. 

Remember, there is a threshold of fat-gain to muscle, even as a skinny guy. The further you push your calories, the higher the chance of some fat-gain coming.

However, get it right, and you'll be able to build 20-30lbs in no time (and more often than not in 3-6 months with the right system).

Along with how many calories you have, it's important to make sure they're coming from the right macros if you want to feel good and maximise your calories to build muscle and improve your health.

That's what I cover in the next part of the guide.

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The Bulking Diet Handbook

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Evidence Based

This article is based on scientific evidence, written by experts and fact checked by experts.

Our team strive to be objective, unbiased, honest and to present both sides of the argument.

This article contains scientific references. These are usually shown through (sources, study) which are clickable links to peer-reviewed scientific papers.