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How to build mass quickly: the ultimate guide for skinny guys

Wie Du schnell Masse aufbaust: Der ultimative Ratgeber für dürre Jungs

How to bulk up fast: The ultimate guide for skinny guys

Part 1


Just can't seem to gain weight? This guide will take you step by step through the mass building process, help you put together a nutrition plan and provide you with a muscle building workout plan.

This guide will teach you the following:

  • How to determine the amount of calories you're eating right now.
  • The best way to customize your diet plan so that you can gain weight in a healthy way.
  • Which foods are best for building mass.
  • How to eat plenty of calories even when you're already full.
  • The best way to train to build quality muscle.
  • How you should supplement to maximize the mass building process.


I was once a skinny boy. A very skinny boy.

And not only that - I was also what many refer to as "skinny fat". Despite the fact that I loved to work out, I looked terrible. It was impossible to see me anywhere in public without a T-shirt.

I found it very difficult to gain weight. Sometimes it seemed like I did nothing but eat from sunrise to sunset, but the scale stayed at 63 to 65 kilos until my last year of high school.

Two and a half years later, when I reached the age of 20, my life had changed dramatically. I weighed 85 kilos with a solid amount of muscle mass, I was stronger than I ever dreamed I would be and girls were talking to me.

This will probably sound like an exaggeration or some kind of sales pitch. I apologize if this is the case, but it is the full honest truth.

In this article, I want to share with you some things that I have learned during these years. I will provide you with specific advice regarding training, nutrition, cardio, recovery and even supplementation.

Confession of a skinny boy: What I did wrong

Looking back on those years, it's easy to see what I was doing wrong and why I couldn't build weight and muscle. Here are the three main reasons I wasn't making progress:

Cardio Overkill

I was working out too much - way too much. During the summer months, I was outside from sunrise to sunset running, playing baseball or basketball, or swimming.

If I wasn't outside, I was inside doing some form of cardio - step-ups, jumping rope or even aerobics (yes, it was the early eighties). It wasn't unusual for me to run 5 kilometers a day, do 45 minutes of step-ups and play baseball for 4 hours. This was a typical day for me.

And here's the problem: even though I was certainly fit and healthy from all that training, I was burning an insane amount of calories. Am I telling you to stop exercising completely? Of course not. Cardio training is a great way to improve your overall health. The problem with too much cardio (and exercise in general) is that it interferes with one of your primary goals - building weight and muscle.

Scientific research supports common sense on this topic. A meta-analysis (1) on the influence of cardio training on resistance training came to the following conclusion:

"Our results suggest that disruptive influences of endurance training are a factor of the modality, frequency, and duration of endurance training chosen."

The bottom line is that if you are currently doing a lot of cardio training alongside your resistance training, this will affect your results. The more cardio training you do, the greater the tendency for it to affect your results.

If your primary goal is to build weight and muscle, then it would make sense not to overdo it with the cardio. This is a competing goal - a goal that is in direct conflict with your weight building goals. For this reason, it makes sense to minimize the amount of cardio you do.

If you are one of the skinny guys, then you should keep your cardio workouts to 3 to 4 hours per week and cardio workouts of 20 to 30 minutes duration. If you play a sport or have an active lifestyle and can't reduce the amount of cardio, then it's time to improve your diet.

You're not eating enough

Most skinny guys think they're eating enough, but in most cases they're just guessing when it comes to estimating their daily food intake. Here's what I recommend: instead of guessing, write down everything you eat for a week. Don't change your eating habits, which means you shouldn't intentionally eat more or less than you normally would during this phase.

At the end of the week, take the time to analyze your food choices during the week. Take a close look at how many calories you have eaten on average over the last 7 days. If you need help, there are numerous websites and books that can provide you with nutritional information on every possible food.

What does this number look like? Is it above 3000 kcal per day? I would bet that your food intake is less than you would have thought.

Building weight and muscle is like any other endeavor in life, which means it takes a certain amount of invested time to become proficient at it. If you want to make it onto a basketball team, then you need to invest some time in your training. Even if you want to play the latest Xbox game to the end, this will require a certain time investment.

If you want to gain weight, then you will need to spend some time analyzing and planning your diet.

You stay weak

Progressive overload is king. Simply exercising is good for your health, but it's not a magical way to build muscle. If you don't push yourself hard in the gym to build strength, you won't build muscle. Stay weak and you'll stay skinny - that sums it up nicely.

When you train for strength, you force your body to respond. In response to these demands, it will build muscle - if you eat enough.

During my teenage years, I did a lot of bodyweight training along with bench presses and curls. I used the same weight over and over again - week after week, year after year - and wasn't able to build any muscle.

No one had ever told me that the body adapts quite quickly to a certain weight and that more resistance is then needed. I thought I could magically "pump up" my chest and biceps using 45 kilos on bench press and 12 kilos on curls.

The next steps - time to gain weight and build muscle

So now we've determined that here's what a skinny kid needs to do:

  1. Stop doing so much cardio
  2. Eat more
  3. Get stronger than he is now

Cardio is the easy part. We can easily control how much cardio we do each week. Let's move on to the next step of our journey and learn how to gain weight the "right" and healthy way.

How to gain weight

This section will provide you with a step by step guide on how to gain weight in a healthy way.

Step 1 - Analyze your existing diet

This is an essential step of the process - so don't skip it by simply making a rough estimate of your average calorie intake instead.

The truth is this... most skinny guys think they're eating enough, but when you ask them how many calories they're eating on a daily basis, they're not sure. This uncertainty is one of the primary components of the problem.

If you can't gain weight, then you need to do something about it. You have a choice between the following two alternatives:

  1. Keep doing what you're doing, which in this case means continuing to guess how many calories you're eating per day while hoping you'll gain weight.
  2. Take control of the situation, learn what you are eating, make the necessary changes and set yourself a goal for a minimum daily calorie intake.

Obviously, the second option is our only real option. Let's get down to business.

Grab a notepad, a computer, a tablet or your smartphone. You will need to write down everything you eat and drink during this week - without exception. If you're not sure of the exact amounts, write things down in a way that makes sense to you. Here are some examples:

  • One side serving of potatoes
  • 1/2 package of macaroni and cheese
  • Almost an entire large glass of milk

Next, use a calorie chart or online calorie calculator to calculate how many calories you ate during the week. Some of this will be guesswork, but that's part of the learning process. Don't drive yourself crazy if you feel that your calculations are not 100% accurate. That's not the point. The point is that you need to learn more about foods, their calorie content, etc.

Now calculate your average daily calorie intake. How many calories do you eat per day? 2200? 2500? Is this number higher or lower than what you previously thought?

Step 2 - Make adjustments to your diet

It's now time to put together some form of structured eating plan and increase your calorie intake. Use the following as a starting point:

  • Calories: Add 500 kcal to your average calculated calorie intake.
  • Protein: Make sure you eat at least 180 grams of protein per day.
  • Fats: Make sure that at least 20% of your daily calorie intake consists of healthy fats.
  • Carbohydrates: After you've determined your protein and fat intake, fill up the rest of your daily calorie intake with quality carbohydrates - fruits, vegetables, grains, etc.

It's certainly okay to eat more than 180 grams of protein per day. Even though studies suggest that you may only need 150 grams per day for your muscle growth, you need to consider the reality that you are currently underweight and your body may be building muscle at a relatively high rate. For this reason, it is better to eat a little more protein per day than less.

A high protein intake is perfectly safe and harmless unless you suffer from pre-existing kidney problems. Eating more protein can also help you balance your diet so that you don't have to be so dependent on carbohydrates. It can be hard to force yourself to eat very high carbohydrate meals if you are not overly hungry.

The recommended 20% should also be considered a minimum. Fat has a high calorie density. Fat provides 9 kcal per gram, while protein and carbohydrates provide only 4 kcal per gram. What does this mean? It is easier to get your daily calorie intake if you increase your fat intake. You won't feel as full because fat has a higher calorie density.

If you find it difficult to eat enough food, then you can consider increasing your fat intake up to 40% of your daily calorie intake. This will make it much easier for you to reach your daily calorie goal.

Step 3 - Weight gain goals

Aim for around 1 kilo per month. Some will see this as slow, but over the year the weight gain will add up to 12 kilos - and almost 25 kilos in 2 years.

If you follow this approach and work hard to get stronger than you are now, using the training plan below, then your weight gain will be quality weight gain. You will build a lot of muscle mass and look great after 2 years.

Some may prefer to gain weight faster. However, while faster weight gain may work for some, it is usually the perfect recipe for fat gain. The human body can only build a certain amount of muscle mass per day, week and month. The faster and more aggressively you push your weight gain, the more likely you are to build more body fat.

And that's not what you want.

The first 2 weeks

Ignore the weight you gain during the first two weeks of your mass-building phase. During this time, you will increase your carbohydrate intake - most likely your sodium intake as well - and the demands on your digestive system. Your body will store more water. This is not rapid fat gain, so don't panic.

After two weeks, your weight gain will stabilize. Weeks 3 and 4 will tell you the real story. Make the following adjustments based on your weight gain during weeks 3 and 4:

  • You lost weight: Code Red! Add 750 kcal to your daily calorie intake. Ignore what the scale says for the next two weeks and make the next adjustments based on what happens 3 to 4 weeks from now.
  • Your weight has stayed the same: Add 750 kcal to your daily calorie intake. Evaluate the rate of your weight gain during weeks 3 and 4 and make the necessary adjustments so that you gain about 1 kilo of weight per month in the long run.
  • You gain weight slowly: Add 250 kcal per day. Evaluate the rate of your weight gain after 3 to 4 weeks and make the necessary adjustments so that you gain about 1 kilo of weight per month in the long term.
  • You are gaining weight at an optimal rate: Keep your calorie intake constant and don't change anything!
  • You are gaining weighttoo quickly: If you are gaining weight too quickly, reduce your calorie intake by 250 kcal and re-evaluate your weight gain after another 3 to 4 weeks.

A note on junk food

You are young, skinny and hormonally strong. Even though you shouldn't eat tons of junk food, it won't hurt you if you consume 10 to 25% of your daily calories in the form of fast food, chips and energy drinks or cookies. This could even help you reach your calorie goals.

Life is all about balance. As long as you eat mostly whole foods with a high nutrient density, it's okay to eat some junk food every day.

Wholesome foods that can help skinny guys gain weight:

The following foods are whole foods that are generally unprocessed or only lightly processed. They are full of good nutrients, inexpensive and high in calorie density - and the best thing about them is that you can find them in any supermarket.

Eating a little of each of these food groups every day can go a long way. You can add small portions of these foods to shakes or meals, or eat them as snacks between meals. They will add a lot of calories (and pleasure) to your diet without making you overly full.

Mass building foods for skinny guys

Protein foods




Minced beef, cooked, 70% lean

120 g


Ham, thick cut

2 slices


Chicken wings with skin

4 wings


Chicken thighs with skin

1 piece


Pork chop

2 pieces, 250 g


Eggs, large

2 eggs


Steak, ribeye

300 g



120 g


Beef, brisket

120 g


Pork sausage

120 g


Fruit and vegetables

Food products




1 large





Avocado, sliced

1 cup



1 cup



1 large



1 large


Sweet potato

1 large



200 g


Nuts and pulses




Peanut butter

2 tablespoons



60 g



60 g



60 g



1 cup


Black beans

1 cup


Dairy products




Whole milk

1 cup



2 pieces


Whipped cream

60 g


Soft cheese

30 g



60 g


Cottage cheese

1 cup


Carbohydrates and cereals




Brown rice, cooked

1 cup


Quinoa, cooked

1 cup


White rice, cooked

1 cup


Noodles, cooked

1 cup


Wheat bread

1 slice


Oils & miscellaneous




Olive oil

1 tablespoon


coconut oil

1 tablespoon


Frozen pizza

1 pizza



1 burger


Beef and bean burrito

1 burrito


Power weight gainer shake for skinny guys

One of the easiest ways to get extra calories is to use weight gainer shakes. The following shake can be consumed once a day and provides 1066 kcal. Simply put all the ingredients in a blender and blend until you have a creamy shake.

  • 500 ml whole milk - 292 kcal
  • 2 scoops of chocolate whey protein - 320 kcal
  • 60 grams of cream - 205 kcal
  • 1 large banana - 121 kcal
  • 2 tablespoons of peanut butter - 188 kcal

Now that you know what you should pay attention to in your diet to achieve optimal gains in muscle mass, we will discuss training and nutrition for skinny guys in the second part of this article


1 Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises. Wilson JM, Marin PJ, Rhea MR, Wilson SM, Loenneke JP, Anderson JC. Link.


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