When I first became interested in putting on some muscle and getting into shape I did what any teenage kid would do and grabbed a FLEX magazine, a Men’s Health and a few other trash fitness and bodybuilding rags and started pouring through the pages. The problem is that these magazines, and nowadays websites, all promote the same garbage: all you have to do to look like Phil Heath or any other pro bodybuilder is workout really, really hard and take the supplements they promote. The unspoken message? It’s all done without steroids.

This is a cruel joke that leaves guys and girls looking to get fit poor and depressed because after working out for weeks, months or years they start to think the reason they don’t look like the guys in the magazines is themselves. They must not be training hard enough, they must have crappy genetics.

The truth is much more complicated than that. There is a physiological upper limit to how much muscle a human can gain without the use of steroids, growth hormones, pro-hormones, insulin, etc… For those interested in the science behind what a natural bodybuilder can accomplish, read on.

Why Care About FFMI?

Steroid talk is an endless debate. Hit up Reddit, T-Nation or BodyBuilding.com and just about every progress post degrades into steroid accusations. Some cases are pretty clear, some less so.

I’ve been around steroid users. I know what an in-shape person who transitions into using steroids looks like, and I see that in progress posts all the time. If everyone operated honestly and gave full disclosure that would be the end of the story. But an infinitesimally small number of people admit to using steroids, even in clear cases. And for me and those looking at progress posts to create a roadmap for their own self-improvement that is a problem. Not that I want to be a vigilante “truth” seeker out to expose the liars, but instead that I want to spread the truth of what a natural bodybuilder can expect.

The fitness industry thrives on selling an image. Unfortunately, if you want to look like the fitness model spread across the cover of a magazine, the only way to get there is with performance enhancing drugs. Not a specific brand of whey protein, nitric oxide pre-workout drink, creatine, amino acids, weight gainers or whatever else you’re being sold. The fitness industry willfully misleads people into thinking the cause for their models’ success is inside a black plastic canister with neon green writing on it, when those products contribute little to nothing to a world-class physique compared to drugs and diet.

Professional sports love to continue the myth. Kids, teens and full-grown adults are sold ideas like that the NFL has a special weight gaining program that can put 40 pounds on a player in a single off-season, which is absolute bullcrap. Sorry folks, you can’t take someone and put 40 pounds of lean mass on their frame in 3 months, especially when they’ve already been an athlete since age 15, without some serious injectable compounds on board. And no, 38-year-old football players who can squat 600 pounds and who have 22-inch biceps are not “genetic freaks.”

When individuals make progress posts and detail their routine, diet, and supplement use down to the smallest detail but leave out the drugs they’re on, they perpetuate the myth. It leads to more people wasting their money and having the wrong idea about what is achievable and how to achieve it. Ultimately, it leads to people leaving fitness because they feel defeated and that’s a real shame.

Bodybuilding is about creating illusions. A lot of the sport is angles, lighting, posing, tanning, peaking techniques, etc…  That’s why it’s more accurately an art than a sport. Combine the already illusory nature of bodybuilding with steroid use, and you’ve got people that hardly resemble humans. These images are attached to advertising which says you can achieve the same look with a quick visit to GNC and the right bicep targeting workout. Because of this many men and women have unreasonably high standards for what is achievable without steroids.

It may be argued that people need something to aspire to, I personally believe that aspirations grounded in truth are much more valuable and conducive to long term success than pie-in-the-sky ideals like modern mass monsters. Anyone can look at Ronnie Coleman and be temporarily motivated, but what happens when you work your ass of for five years and never come close?

I can’t solve all those issues, but the first step is educating newcomers to the weight room on what they can achieve naturally so they can enter with realistic expectations.

The Fat-Free Mass Index

The gold standard for identifying natural bodybuilders is the fat-free mass index (FFMI). FFMI is defined by the formula (fat-free body mass in kg) x (height in meters)-2. A slight correction of 6.3 x (1.80 m – height) will normalize these values to the height of a 1.8-m man.

Bobby PandurA gold standard was established for screening drug-use among bodybuilders called FFMI (Kouri et al., 1995), much of the the data used to tabulate the FFMI was derived from pre-steroid era bodybuilders.

Data was taken from 84 steroid users and 74 non-users first, then all the Mr. America winners from 1939-1959 were added to the analysis. They concluded that a soft upper limit of 25 was appropriate for non-steroid bodybuilders. I say soft, because a few of the pre-steroid Mr. America’s exceeded this value, the highest FFMI value was 28, the average was ~25.

It should be noted that the max FFMI values are based on bodybuilders in contest condition (e.g. 3-5% body fat), for overweight and fatter individuals, the formula loses validity.

Remember, for the FFMI calculation to work, percent body fat, height and weight need to be as accurate as possible.

FFMI Calculator

Norms for FFMI in Men

  • 16-17 = Well below average (< / – 20th percentile)
  • 18-19 = Average (25-50th percentile)
  • 20 = Above Average (50-75th percentile)
  • 21 = Well above average (75-90th percentile)
  • 22 = Excellent (95th percentile)
  • 23-25 = Superior (Off the charts for normal adult men, but in the top 85-95th percentile for Natural bodybuilders)
  • 26-27 = Some Natural bodybuilders could get to this level (God Genetics)
  • 28-29 = It is possible but very unlikely to reach this level Naturally
  • 30 or above = We can say with nearly 100% certainty that this person is not natural

I’ve always been a fan of classic era 1970’s bodybuilders, preferring their more aesthetic looks over current day mass monsters. What’s interesting though is that Arnold Schwarzenegger at 6’2″ and 235 lbs had an FFMI that was ~28.7, and he was a known steroid user. So, for even the most genetically gifted natural bodybuilder anything close to a classic era Arnold build is all but a pipe dream.

As for modern mass monsters? Phil Heath’s FFMI is an astonishing 35+.

Measuring Success Without Steroids

FFMI is an interesting tool for separating natural bodybuilders from those using non-natural means to gain muscle. However, I’m more interested in using the tool personally than policing others. It’s interesting to play with the calculator to see what weights and body fat combos you would need to reach to hit the upper limits of natural bodybuilding. Doing so results in much more realistic goals for the natural bodybuilder (target 25) or those of us just looking for a good aesthetic build (21+). Give the calculator a go and get an idea for what you can achieve without steroids.