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# Predicting Maximum Muscular Bodyweight: The Equation watch

1. Quoted below, not my own writing. Attached is my .xls to calculate it for you, if you want. Just fill in the cells next to the bold parameter names, and the grey-shaded cells give you the results.

Predicting Maximum Muscular Bodyweight: The Equation

The equation below predicts the maximum lean body mass someone of a given height and bone-structure can achieve without the use of anabolic drugs

Maximum lean body mass = (3.285H + 9.437A + 5.840W - 186.449) x (%bf / 227.27 + 1)

where,
H = Height in inches
A = Ankle circumference at the smallest point
W = Wrist circumference measured on the elbow side of the styloid process.
(The styloid process is the bony lump on the outside of your wrist.)
%bf = The body fat percentage at which you want to predict your maximum lean body mass

Very thin ectomorphic men can expect to attain about 95% of the lean body mass that the equation predicts. Likewise, very endo-mesomorphic people, who have disproportionately wide hips and thick torsos, and people whose joints are uncharacteristically small, may be able to exceed the prediction by up to 5%.

So, using this equation, for a 5'9" (69 inches) tall bodybuilder at 10% body fat with 7.0" wrists and 8.7" ankles the equation would yield:

Maximum lean body mass = (3.285 x 69.0 + 9.437 x 8.7 + 5.840 x 7.0 - 186.449) x (10 / 227.27 + 1) = 170.4 pounds.

To convert maximum lean body mass to maximum bodyweight at any given body fat, use this equation:

Body weight = (Lean body mass / (100 - %body fat) ) x 100

Using our example bodybuilder, at a lean and healthy 10% body fat his total bodyweight would be:

Body weight = (170.4 / (100 - 10) ) x 100 = 189.3 pounds

The formula was developed as an amalgamation of data from past and present drug-free bodybuilding champions and anthropometrics data from the U.S. Army, Navy, and several anthropometrics studies done by various organizations throughout the world (for ergonomic designs, etc.). In addition, a comparison was made with the fat-free mass indexes of champion bodybuilders, as presented in the work of Dr. E. M. Kouri, et. al. A mathematical regression was done to obtain fits based on the heights, wrist sizes and ankle sizes of elite-level drug-free bodybuilding competitors. As the final fit was sufficiently linear in nature, the equation was then linearized to make it more "user-friendly", without sacrificing accuracy.

Table 1 presents a list of drug-free bodybuilding champions both past and present with their actual weights and the weights predicted by the formula. The current champions are unnamed because of the "sensitive" nature of body weights and measurements to actively competing bodybuilders.

Table 1: Bodybuilder Actual Weight Predicted Weight
Clarence Ross 198 198.1
John Farbotnik 195 196.2
George Eiferman 195 195.5
Reg Park 214 214.5
John Grimek 203 203.1
Jack Delinger 195 193.3
Steve Reeves 213 214.1
Current World Champ. "A" 180 180.7
Current World Champ. "B" 175 174.6
Current National 3rd Place 174 174.0
Current National 4th Place 184 185.5

The greatest error in the above predictions is 0.87%. So, as you can see, the equation is quite accurate for this group of bodybuilders. In addition, these lifters are of varying heights and bone structures to further illustrate the validity of the predictions.

If you are lifetime drug-free, use this formula to set a realistic and accurate bodyweight goal for yourself. If you're like our example bodybuilder of 5'9" tall, with 7" wrists and 8.7" ankles, then forget about weighing a lean 230 pounds. If you get to a lean 190 pounds you'll be carrying as much muscle, with respect to your frame, as an elite-level natural bodybuilder.
Attached Files
2. BW calc.zip (1.8 KB, 143 views)
3. Well according to that at 11% bf i could be at 180.3lbs max. Thats my current bf and im around 166lbs. So max amount of muscle i can hope to pack on is estimated at about 15lbs. Great. Lol. Of course my measurements arent precise enough for a definite predicted, but i guess its a decent prediction.
4. i just exceeded it...
5. (Original post by focusST)
i just exceeded it...
ROIDS
6. I wondered how long it would be before someone said they had exceeded the prediction... I'm still a good 1-2 stone off and its the closest I am going to get I should think.
7. yea I'm about 20lbs away and I can't imagine myself reasonably exceeding it.

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