For decades it’s been quietly known that height is positively correlated (+0.24) with IQ and that weight/height ratio is negative correlated with IQ (-0.15). It is interesting to apply these correlations to the World’s shortest strong man and the World’s strongest short man, Andrew “Stumpy” Raynes, who was reportedly 5’3″ and 275 lbs when he achieved these distinctions.
Sadly, despite being a British hero, I suspect the Queen (like a lot of older upper class women) and the snobby men around her would have HATED him, not because he’s short, but because the combination of short and muscular is caveman looking and thus the opposite of Western civilization. The Grenadier Guards are supposed to be over 6’2″ and svelte and the Queen goes weak at the knees for tall nerds with glasses.
Indeed their short muscular build is one reason Neanderthals were long dismissed as primitive brutes incapable of thinking or running, stooped over and inferior to modern man in every way, physically and mentally.
Stumpy’s height subtracts 9 points from his expected IQ
Let’s begin with Stumpy’s height. Given that he is 2.4 standard deviations shorter than the average white male of his generation, and given the 0.24 correlation between IQ and height, we’d expect his IQ to be 0.24(2.4 SD) below the white mean, or roughly 91 (British norms).
Stumpy’s weight/height ratio subtracts 5 points from his expected IQ
Weight/height ratio is usually calculated using the body mass index formula which is your weight in Kg divided by your squared height in meters. Don’t waste time doing the math when there are so many convenient calculators. When we calculate this for Stumpy we get 48.7.
Using table 15 of this document, we see that the mean BMI for non-Hispanic white males in the age range when Stumpy competed is 27.7 and the SD (which can be calculated by multiplying the standard error by the square root of the sample size) is 9.9, which means Stumpy’s BMI is +2.12 SD.
So based on the -0.15 correlation between IQ and BMI, his expected IQ is -0.15(+2.12) = -0.32 SD or about 5 points below the UK mean. defined as 100.
Stumpy’s fat-free weight/height ratio may subtract 15 points from his expected IQ
Of course BMI underestimates how truly exceptional Stumpy’s physique is because elite strongman typically have only 18.7% body fat. This suggests Stumpy’s fat-free body weight was (0.813)(275 lbs) = 224 lbs, giving him a Fat Free Mass Index of 39.7.
To put this number in perspective, let’s compare Stumpy not to the general population like we did before, but to the weight lifting population because they, like Stumpy, are closer to their genetic potential for fat-free mass. Compared to steroid users, Stumpy’s FFMI is an astonishing +6.78 SD and compared to non-steroid lifters, he’s +9.9 SD. Even if we conservatively assume that Stumpy is part of the steroid population, the odds of a random steroid lifter having an FFMI this high are about one in 190 billion assuming a bell-shaped curve.
If we assume the correlation between IQ and FFMI in the steroid population is the same as the correlation between IQ and BMI in the general population, and if we assume Stumpy’s part of the steroid population and that the steroid population has the same IQs as the general population, then his predicted IQ would be -0.15(+6.78 SD) = -1.02 SD or IQ 85.
The COMBINED effect of Stumpy’s height and FFMI on his IQ
The whole point of using (fat-free) weight/height ratio instead of weight is to eliminate the effect of height from weight. Thus the correlation between FFMI and height should be zero. A zero correlation has disasterous implications for Stumpy’s expected IQ because the deductions predicted from his height (9 points) are completely independent from the deductions predicted from his FFMI (15 points). That means we can simply add them and predict Stumpy’s IQ is 24 points below the UK mean of 100 which is IQ 76.
Of course, the standard error around this estimate is so large that I would take it with a grain of salt, but to paraphrase a famous scene in Animal House, short, stumpy and stupid is no way to go through life.