How much muscle can you gain at most? As a natural

Scroll this

It’s a question that is often answered way too positively in most bodybuilding magazines and supplement advertisements. How much muscle mass can I naturally gain in a month or year? The real answer to that question may surprise you.

Key points:

1.   A male natural bodybuilder can gain a maximum of 10 to 18 kg of muscle mass in his life through strength training (average 13 kg). The exact amount depends on body type and other genetic conditions.

2.   In the first two years of your training career, you can already realize about 75% of your muscle growth potential, provided you train continuously according to a well-thought-out program, with the right nutrition and enough rest to recover. After three years you will already be at 85% to 90% of your genetic potential. In practice, it usually takes much longer, because training, nutrition and rest are often not optimized.

3.   You don’t have to train optimally to grow. An hour of training per week can be enough for beginners to achieve perhaps 70% of the maximum muscle growth. Over time it becomes increasingly difficult to build muscle mass and you will have to go towards 10-20 sets per muscle group per week for maximum muscle growth.


Don’t be fooled by the misleading pictures of competitive bodybuilders in magazines and on fitness websites. If you want to compete at the highest level in the world of bodybuilding, you will have to spend an average monthly salary on performance-enhancing drugs. Apart from the costs for food and supplements. How many kilos of muscle can you gain naturally?

In this article we assume that you are a natural bodybuilder and therefore only use ‘aids’ that are available legally and without a doctor’s prescription (creatine for example).

As a natural, your genetic ceiling is your upper limit. Although you will never reach that ceiling in practice ix ] , this means that you have usually already reached your potential after a few years of (optimal) training.

The use of anabolic steroids in bodybuilding has created a rather cloudy picture of what is possible in this sport naturally, ie without ‘substances’. Perhaps you envision a physique that extends far beyond your genetic capabilities. And perhaps your great example in bodybuilding is an avid steroids user, who throws sand in your eyes with his adoration for rice, chicken and broccoli.


The physique you can achieve as a bodybuilder depends first and foremost on your physique and the associated genetic conditions.

From science we can distinguish different body types (somatotypes). A classic classification is that of ecto-, meso- and endomorph, even though it actually stems from psychology. The disadvantage of this classification is that one is by no means always one of these types, but often an intermediate form.

Gruber and colleagues developed another system for body type determination, the Fat-Free Mass Index (FFMI) x ] , in 2000 . Their guidelines for men, expressed in kg/m2, are as follows:

  • 18: slightly built with little muscle mass
  • 20: medium muscle
  • 22: clearly muscled
  • 22-25: usually not achievable without years of strength training
  • >25: probably not achievable without the use of anabolic steroids

In principle, you can only determine what your ‘original’ body is when you are fully grown, or at least only when you have already been through puberty for a number of years.

Are you or were you skinny as an adolescent, with relatively little muscle mass and muscles that are long in shape? Can or could you eat a lot without gaining (much) weight? Then you are probably an ectopmorph, or you fall in the FFMI index under the lightly built. You can then build up a fair amount of muscle mass, but it will be relatively difficult or slow. Also remember that you originally have little muscle mass. So you have to build a large part of your physique yourself, so the end result may be less spectacular than you hope for. In the FFMI index you probably won’t get past 20-22.

Mesomorphs and endomorphs can grow muscles more easily and already have more muscle mass. So, even as naturals, they can get quite big through strength training (22-25 or maybe even higher in the FFMI index). It will take them more effort to also stay lean, something that the ‘ecto’ will do more easily.

The fact that some peers are much more muscular than you, even if they do not or hardly train, is often purely a matter of genetics. Which is not to say that you should despair as a signed ectomorph. You may still be able to get quite jacked, depending on how much you deviate from the genetic average.


As a newcomer to the gym, you will find that you can achieve muscle growth quite easily and quickly, even if your training, nutrition and rest are still anything but optimal. The body of an advanced strength athlete is adapted to the toughest training conditions, while that of a newbie will experience even the smallest training stimulus as ‘new’ and therefore as a growth stimulus.

Making progress means that our body has to constantly adapt to larger and heavier training loads (adaptation). Although your muscles can continue to adapt quite quickly, your bones, joints, tendons and nervous system cannot. It is therefore not possible to add new weight over and over again: sooner or later you will reach a plateau.

For advanced students, the principle of reduced or decreasing returns therefore applies: much more is needed to make progress and that progress is also much less.

The principle of diminished returns. Source: Sean Nalewanyj


Although predicting muscle growth is and remains difficult, thanks to the work of a few scientists, we can give some (rough) guidelines.


The most complex and perhaps most reliable model for predicting muscle growth is that of natural bodybuilder Casey Butt, who collected ankle and pulse measurements from natural bodybuilders between 1947 and 2009. He developed a calculator that calculates the maximum muscle potential based on height, ankle and wrist size, combined with body fat percentage. But then you have to have these numbers.


Based on literature studies and anecdotal evidence , physiologist and author Lyle McDonald developed a simpler model ii ] that predicts the next annual growth potential.

Yes, you read that right: after four years of serious (ie productive) training, you will only gain a maximum of one kilogram of lean muscle mass per year. Again, assuming you’ve been training optimally all these years.


Researcher and fitness consultant Alan Aragon, partly based on data from his own practice, came up with a model that translates the muscle growth potential to the training level: beginner, advanced and advanced i ] .

A beginner usually refers to someone who trains for a maximum of one year. An advanced is someone who trains for one to three years and an advanced is someone who trains for three years or more. Again assuming that there is optimal training, nutrition and so on. In itself, this is a vague and inaccurate definition. As far as we are concerned, your strength level says more about your training level. In this article you can learn which training level corresponds to your strength level. Even someone who has been training for three years can be a beginner in that respect. Are you completely untrained? Then the most optimistic numbers for the beginner probably apply to you.

Below the Alan Aragon model for men. Women can simply divide the percentages and numbers that follow by two to get a rough idea of ​​the progress they can expect.

What we see at work above is the aforementioned principle of diminishing returns. In other words, you will have to work harder and harder, while getting less and less in return. Thankful, isn’t it?


Finally, the “No Bullshit Formula” of coach and author Martin Berkhan, which he based on his observations of natural bodybuilders in competition form, so with fat percentages around 4-5% in men xi ] . His calculation reads:

height in cm – 100 = maximum weight in kg, in competition form 

The results of this formula would roughly correspond to the more complex ones of Casey Butt xii ] . Nevertheless, we feel that it is very general, because height does not necessarily say anything about body type (ecto, meso or endo).


Websites and magazines almost always talk about optimal training for muscle growth. In other words, what should you do and not do to achieve as much muscle growth as possible within a certain time frame. But muscle growth does not go away: it is not a problem if you spend fewer hours in the gym and therefore build up muscle mass less quickly. The most important thing is that you keep making progress.

What is the minimum you need to do to achieve significant muscle growth? According to a scientific review by, among others, muscle growth expert Brad Schoenfield, four (!) sets per muscle group per week are enough to grow iii ][ iv ] . This means that you can train your entire body for muscle growth with roughly three half-hour sessions a week.  According to coach and author Greg Nuckols, one hour of training per week can be enough to achieve perhaps 70% of maximum muscle growth v ] .

So you don’t need nearly as much effort as you might think, although we assume that your diet is in order (sufficient proteinsevenly spread over the day) as well as your recovery (especially your sleep). And the longer you train, the more it takes to maintain muscle growth. An average natural bodybuilder (thus with one to two years of experience) needs 10 to 20 sets per muscle group to grow.


Based on the above theory, we arrive at the following general guidelines:

1. A male natural bodybuilder can gain a maximum of 10 to 18 kg of muscle mass in his life through strength training (average 13 kg ). The exact amount depends on body type and genetics.

2. He will already realize 75% of that mass in the first 2 years, provided nutrition, training and recovery are optimized. After 3 years he is already at 85% to 90% of his genetic potential.

3. You don’t have to train optimally to grow. An hour of training per week can be enough for beginners to achieve perhaps 70% of the maximum muscle growth. Over time it becomes increasingly difficult to build muscle mass and you will have to go towards 10-20 sets per muscle group per week for maximum muscle growth.


Submit a comment

Your email address will not be published. Required fields are marked *