Your maximum muscular body-weight depends mostly on your height and bone-structure. Tall people can build more muscle mass than short people. People with large, thick frames can gain more muscle than people with narrow builts and small wrists/ankles like me.
Casey Butt Phd has come up with formulas to determine the maximum amount of muscle mass you can gain naturally. His research is based on the muscle size of the world’s top bodybuilders before anabolic steroids existed. I’ve turned Casey’s formula in a simple table below.
|Height||Maximum Body-weight||Maximum Biceps Size|
|1m62 / 5’4″||78kg / 172lb||41.5cm / 16.3″|
|1m67 / 5’6″||82kg / 181lb||42.1cm / 16.6″|
|1m73 / 5’8”||86kg / 190lb||42.7cm / 16.8″|
|1m77 / 5’10”||90kg / 199lb||43.4cm / 17.1″|
|1m83 / 6’0”||94kg / 207lb||44cm / 17.3″|
|1m87 / 6’2”||98kg / 216lb||44.6cm / 17.6″|
|1m93 / 6’4″||102kg / 224lb||45.3cm / 17.8″|
|1m98 / 6’6″||106kg / 233lb||45.9cm / 18.1″|
These numbers assume a wrist size of 17.8cm/7″, ankle size of 22.9cm/9″ and body-fat of 10%. The biceps size is contracted at the largest point. These numbers are for males only. The female muscular potential is lower since they’re usually shorter, smaller and have less testosterone.
These numbers are based on the achievements of the best bodybuilders that ever existed, including Reg Park. It’s therefore unrealistic to expect gaining as much muscle. These lifters had better work ethics and genetics than the rest otherwise they wouldn’t have become champions.
So be proud if you reach 90% of your muscular potential in lean condition. I’m 5’8″ with 6’7″ wrists. I weigh about 175lb with maybe 12% body-fat. That’s 90% of 190lb. This is why although I’m not a big guy, and may look small on paper, people I meet always notice I lift weights.
These numbers show most guys won’t build a 200lb lean and muscular body. The average height for males in the US is 1m75/5’9″. Unless you’re taller, the only way to get to 200lb is to let your body-fat increase… or take anabolic steroids. Working hard won’t make it happen for natural lifters.
The point isn’t to demotivate you. Quite the opposite – I don’t want you to get demotivated because you set unrealistic goals like 21″ ripped arms. Reg Park had 18.5″ arms, competed at 214lb and was 6’1″ tall. He could Squat 600lb and Bench 500lb. You’re unlikely to do better than him. Really.
It’s true that training and nutrition methods have improved. People gain strength and muscle faster today than in Reg Park’s time. But human genetics haven’t changed – there’s still a limit to how much muscle you can gain naturally. And this still depends mostly on your height and frame size.
What has changed a lot is anabolic steroids. Arnold Schwarzenegger competed at 235lb/6’2″. Three decades later Ronnie Coleman competed at 300lb/5’11”. They both worked hard, both Deadlifted over 700lb, Arnold even admitted using drugs. But one clearly used more to get 65lb bigger…
That’s why natural bodybuilding competitors rarely weigh over 200lb. They can’t get lean enough to show up ripped. Most people compete in the lighter 165lb class because that’s where you end when you drop to single digit body-fat. 200lb ripped, life-time natural physiques are rare.