How Much Muscle Can You Gain Naturally? (With A Calculator)
How Much Muscle Iron Paradise Fitness

Here's How Much Muscle You Can Gain Naturally, Including A Free 'Genetic Potential' Calculator 

"How much muscle can I gain naturally?" A question every person with even a passing interest in fitness has asked. But what's the answer?

Most will say it's impossible to say. There's too many variables. And, of course, " depends."

And while it's not an exact science, there is a way of assessing your genetic potential and how much muscle you can build.

In this article, you'll discover what defines your genetic potential, how to calculate how much muscle you can gain, and how to fulfil that potential. With that said, here's what the article covers:

  • The factors that define your genetic potential.
  • 2 online calculators to help you easily work out how much muscle you can potentially build naturally.
  • A method for assessing if your goals are achievable without drug enhancement.
  • A guide on how to determine if your favourite social media personality is as drug-free as they claim.
  • Another online calculator to help you determine how much muscle you can build in a year.

So, if you want to find out more, read on.

And if you'd prefer to listen to the audio version of this article, click the play button below.

What Factors Define How Much Muscle You Can Gain?

How Much Muscle Iron Paradise Fitness

Before we launch into calculating how much muscle you can build, let's look at the factors influencing what's possible.

Genetics play a huge role in defining your potential. After that, the quality of your training and nutrition determines how much of that potential you fulfil. In my experience, most people who blame genetics or claim to have hit their genetic ceiling are not even close.

In reality, building muscle is hard. It takes consistent effort over a long period of time. And most people aren't prepared to put in that work. So they resort to, "'s my genetics" as the default excuse.

That said, there is an obvious genetic component to the discussion. So here's what the research tells us about what's involved in determining how much muscle you can build.

Birth Weight:

According to a 2007 study, a higher birth weight is positively associated with greater long-term potential for muscle gain. In fact, for every 1kg difference in birth weight you can expect c. 4.1 kg of muscle gain over a lifetime.

Initial Lean Mass:

A study in 1994 looked at potential muscle gain over a 12 week period, based on subjects' starting levels of lean mass. The conclusion of the study indicated that the more muscle you have to begin with, the more you'll gain over time.

Joint Size:

An analysis of 501 participants looked at the association between ankle and wrist size, and free fat mass (FFM, ie muscle). It highlighted a positive correlation between greater joint size and increased FFM.

Wider Frame:

A 2007 study looked at the levels of FFM mass in powerlifters. The research showed a positive association between greater FFM and those athletes with wider frames.

So what conclusions can we draw from this?

In a nutshell, your parents have a lot to answer for. Ultimately, how much muscle you can potentially gain over your lifetime is out of your hands. Although, it's worth bearing in mind these studies are looking at associations. Consequently, they're not designed to provide strict limitations. After all, you may be an outlier who defies the trend.

How To Calculate How Much Muscle You Can Build?

Based on the available data, many formulas have been developed to help calculate your genetic potential. The simplest of which are based on height. But these don't cater for variances in physiques. For example, according to these calculations, a taller person will have the potential to build more muscle than a shorter person. However, we've all seen that short, heavy-set dude badass in the gym, right?

Casey Butt develop a formula to account for this. It's more complicated, which is why I've simplified it for you in this handy calculator. Sadly, his research only involved men, so it's probably not accurate for women.

For this calculation, you'll need to know your:

  • Height (cm)
  • Ankle Circumference (cm). Measure at the smallest point.
  • Wrist Circumference (cm). Measured at the Styloid Process (the boney lump).
  • The body fat % at which you want to predict your maximum lean body mass. It's recommended you pick 8-10% here. Any lower probably isn't sustainable for very long.


Other Evidence-Based Methods For Calculating How Much Muscle You Can Build

How Much Muscle Iron Paradise Fitness

Casey Butt's formula isn't the only method for calculating how much muscle you can build. Martin Berkhan has developed an incredibly simple calculation based on his experience in coaching thousands of people to get very lean.

His calculation is based on your weight at competition levels of body fat (5-6%). So "lean AF" to give you the technical definition:

The calculation: Stage Lean Weight = Height (cm) - 100 (instead of subtracting 100, you can use 98 & 102 to provide a range).

Calculating Your Competition Weight Potential:

If you're interested in using Martin's formula, use the calculator below to understand you maximum body weight at 5-6% body fat.

A word of caution! As this calculation is purely based on height, there's minimal consideration for genetic differences. Again, treat it as a guide, not an absolute.

Also, it’s sadly only for dudes (sorry ladies, I didn’t make the formula).


Is That Dude Natural? A Calculator To Help You Find Out...

How Much Muscle Iron Paradise Fitness

You might surf through social media and wonder if the physiques you see on a daily basis are achievable without a trip to your local 'underground pharmacy'.

Often, comparing yourself to others leaves you disheartened and deflated about your own progress. And, in many cases, these models and athletes claim to the bitter-end they achieved everything naturally. But did they really? In many cases, you can rely on what they say about as much as the bullshit supplements they're trying to sell.

But it's easy to dismiss any well-sculpted physique as the product of steroids.

So how do you know who's telling the truth and who isn't? The answer is, unless the dude (or dudette) is freakishly big, you DON'T!

And, unless said person is trying to pull the wool over your eyes for their own personal and financial gain, does it even matter?

Understanding Your Genetic Potential

Being accused of steroid use is something I've dealt with in the past. As a natural bodybuilder, the social media trolls flick between the extremes of "Do you even lift?..." and "Must be on the juice!" with a baffling degree of idiocy.

For example, take a look at these pictures.

After posting this picture online, I received multiple comments that my transformation was only achieved through steroid use (which it definitely wasn't).

Before After 2.0 Iron Paradise Fitness

Weirdly, this picture (taken over a year later) had the same keyboard warriors wondering if I even lift. P.S. I actually have MORE muscle in this pic!

So, the lesson here is that body fat, lighting, angles, and high-quality photography can enhance the look of any physique.

That aside, there IS a way for you to assess if someone is or isn't bending the genetic rules.

Eric Helms developed a calculation based on the Free Fat Mass Index (FFMI). Using data from a study of 83 steroid users and 74 non-steroid users, Helms' calculation estimates how much muscle can be built naturally.

The calculation: FFMI = fat free mass in kilograms/(height in meters)2

Calculating Your (Or Someone Else's) Genetic Potential:

You can use the calculator below to assess your own FFMI and genetic potential. Simply enter your height, desired body weight, and target body fat percentage. Then the calculator will give you an FFMI score, which you can use to determine if your goals are achievable naturally. And if you know the vital statistics of your favourite Insta model, you can use the calculator to assess their physique as well.

Interpreting your FFMI:

  • 16 - 17: below average
  • 18 - 19: average
  • 20 - 21: above average
  • 22: excellent
  • 23 - 25: superior
  • 26 - 27: scores considered suspicious but still attainable naturally
  • 28 - 30: highly unlikely scores to be obtained naturally without steroid usage

As a guide, an FFMI score of 25 is the ceiling for most natural bodybuilders.

Word of caution! Measuring your body fat is highly inaccurate, unless you have access to a DEXA scan. So bear this in mind when you are assessing how much muscle you're able to build.

Sadly, the study used to develop these calculations used exclusively male athletes. Again, this means there may be a degree of inaccuracy for females (sorry ladies!).


How Much Muscle You Gain Comes Down To Training And Nutrition

Genetics aside, your ability to build muscle is driven by what you do in and out of the gym.

You can have the best genetics in world, but if you train poorly and half-ass your nutrition, you'll fall short of your potential. So it's important to focus on putting the basics in place as soon as possible. Then, with consistent execution, you'll begin to build muscle to the extent your genetic potential allows.

And if you're unsure where to start, use these "Fuck-Ton Of Muscle Starter Kit" infographics to help.

P.S. For more useful graphics like these, check out the Iron Paradise Fitness Instagram page (click here to follow the account @iron_paradise_fitness).

In summary, your priority number one is training. Basically, without the appropriate stimulus, your muscles won't adapt and grow.

This might lead you to ponder what training programme would yield the best results. Another great question!

It just so happens you're in luck. If you click here, you can download the FREE Lean Life Kickstarter Pack. In it, you'll find everything you need to take the frustration, headache, and overwhelm out of getting your journey to a leaner, healthier life off to the best possible start. Here's what's included:

  • 4 week beginner's training programme.
  • Evidence-based guide to calories eBook.
  • Access to a free online calorie and macro calculator.
  • How to conquer your uncontrollable cravings eBook.
  • Lean Life Recipe Book with over 30 delicious, diet-friendly recipes.

So if you what to start building muscle, losing body fat, and living a healthier life, grab your kickstarter pack here.


The Bottom Line On How Much Muscle You Can Gain Naturally

How much muscle you can gain naturally is largely driven by your genetics. Picking good parents is likely to be the biggest determining factor in the amount of muscle you build. But you still need to do everything right to get anywhere near your genetic potential.

The ceiling for how much muscle you can build may be dictated by factors outside of your control, but this shouldn't deter you from giving your all to training.

Research provides an indication of your genetic potential. However, this isn't a fixed limit. And there will always be exceptions and variations to the rule.

Also, there's the small matter of needing to everything right along the way.

In truth, most people never come close to their genetic potential. Ineffective training and sub-par nutrition results in years of mediocre gains. So unless you've genuinely maxed out on how much muscle you can build, continue to focus on the basics of training and nutrition. Develop consistency, enjoy the process, and let time take it's course.

"But Simon. How much muscle can I build in a year? How do I know if I'm progressing at the right speed?"

Good question. And the next logical progression after assessing how much muscle you can build over the long term.

Thankfully, there's an evidence-based way to set your expectations.

How Much Muscle Can You Gain In A Year?

Lyle McDonald has developed guidelines for determining your rate of muscle growth, based on the years of training under your belt.

  • 1 Year Of Proper Training = 20-25 lbs of lean muscle per year
  • 2 Years Of Proper Training = 10-12 lbs of lean muscle per year
  • 3 Years Of Proper Training = 5-6 lbs of lean muscle per year
  • 4+ Years Of Proper Training = 2-3 lbs of lean muscle per year (not worth calculating)

The important thing to note here is that the estimations are based on the number of years of proper training AND nutrition. So, throwing a few weights around, attending a few body pump classes, and being lax with your nutrition, doesn't count.

In fact, if this is you, class yourself as newbie when using the calculator.

The "How Much Muscle Can I Gain In A Year?" Calculator:

Using Lyle's guidelines, here's a simple calculator you can use to set your expectations for the next 12 months. And if you HAVE been managing your training and nutrition properly for a number of years, the news is bleak. In fact, I've not even included you in the calculations, because your rate of muscle gain is almost immeasurable.


Here's What To Do If You Want To Build The Most Muscle Possible Over The Next 12 Months

Online Coaching Iron Paradise Fitness

After reading this article, you might be excited at the prospect of transforming your physique and fulfilling your genetic potential. And to do that, you need training, nutrition, and mindset to be aligned.

Through my online coaching programme, The Lean Life Method, I'll help you lose fat, build muscle, and build the body you've been striving for. Ultimately, taking the guesswork out of training and nutrition so you can live a leaner, healthier life for good. 

With The Lean Life Method, you’ll learn a simple, stress-free way to lose fat, build muscle, and feel more confident and healthy than ever before, without torturing yourself in the gym, avoiding wine and pizza, or killing your social life in the process.

And I understand the fact you're unsure about coaching. After all, you've spent thousands on pills, powders, and programmes that delivered nothing. So what's different about me?

The simple truth is this... I get results and I'll teach you everything you need to know so you can maintain those results.  So answer me this.

  • How much precious time are you spending trying to figure out what's right, instead of making progress?
  • Are you sick and tired are you of never seeing the results your hard effort deserves?
  • How much stress and frustration is your lack of progress adding to your life?

lack of clarity might be holding you back from living the leaner, healthier life you deserve.

Schedule A Consultation Call

Click here find out more about the results, people just like you are getting with the programme. And if you feel like my personal 1:1 support and coaching could bridge the gap between where your are now and what you're trying to achieve, schedule a free consultation call. But don't worry, there's no hard sell. It's an opportunity to find out if we're a good fit to work together.

So, if you're even the slightest bit interesting, click here for more information.

But for now, all I’ll say is, keep living the Lean Life. And I’ll see you soon.

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