December 12, 2008

Height and weight

In October, the government published the latest version of their National Health and Nutrition Examination Survey (NHANES) study of sizes, "Anthropometric Reference Data for Children and Adults: 2003-2005," which is of great interest to clothing manufacturers. And you might find it interesting too.

Let's look just at the medians for people ages 20-39, since they are most likely to be in the marriage market.



Height
Age 20-39 Males Females Diff
NH White 70.4 64.8 -8%
Black 70.0 64.2 -8%
Hispanic 67.1 62.6 -7%

So, the average Non-Hispanic white man between 20 and 39 is 5'-10.4" tall (178.9 cm.).

People are measured while wearing foam slippers.

As you can see, whites are a little taller than blacks, with Hispanics lagging more than a standard deviation behind.

The average height of the Hispanic population is probably bipolar, depending upon whether they were born in the U.S. or not. At the illegal immigrant march I observed in Van Nuys, CA in 2006, the average participant was very short, with men averaging well under five and a half feet tall. (This suggests, by the way, that U.S.-born Hispanics didn't care enough about illegal immigrants to turn out in large numbers.)

The male-female gaps are similar for all three groups, with women averaging 92%-93% of the height of their menfolk.

The 95th percentile for younger white males is 6'-2.9", for blacks 6'-3.1", and for Hispanics is 6'-0.3" For both white and black women, age 20-39, the 95th percentile is 5'-8.7", while for Hispanics its 5'6.5".

The standard deviation for white males appears to be a little more than 2 1/4th inches and for other males around 2 1/2 inches. The average NBA player is between 6'-7" and 6'-8" (and has been for the last 20 years). I believe that's measured in socks rather than in shoes, although college heights tend to be exaggerated. For instance, last year's UCLA All-American center Kevin Love was listed by UCLA at 6'-10" but was measured by the NBA for the draft at 6'-7.25.

Assuming a black median of 5'-10" and a standard deviation of 2.5", that means that 6'-8" is four standard deviations from the mean. Assuming that height is normally distributed (a big assumption),then one standard deviation above the mean is 6'-0.5 and that is the 84th percentile. Two s.d.'s up is 6'-3" and that is the 97.7th percentile. Three s.d.'s up is 6'-5.5" and that is the 99.87th percentile. And four s.d.'s at 6'-8" would be the 99.997th percentile.

Five s.d.'s would be 6'-10.5" (a seven-footer in recruiting parlance) and if the population is normally distributed, only one would be born in America, black or white, each year. So, the population probably has "fat tails" when it comes to height.

Still, it's worth noting how rare truly tall men are. When Colby Cosh asked who was the tallest man famous for something not height-related, his readers mostly came up with novelist Michael Crichton at around 6'-10" and economist John Kenneth Galbraith at maybe 6'-9". (The pretender to the throne of Albania is often said to be 7 feet tall, but I can't say how accurate that is.)

When I was young and naive, I said to a friend who had gone to three colleges, "Even if you are really tall, you have to be a good athlete to play college basketball." He said, "No, you don't. You just have to be tall. On every campus I've been on, there were two seven footers, and they were the starting and back-up centers on the basketball team." When I was at Rice, there were two guys on the basketball team listed at 6'-11" and, sure enough, they were the tallest people on campus. When I was at UCLA with 35,000 students, there were two seven footers, the starting center Stuart Gray at 7'-0" (who spent 8 years in the NBA as a backup center) and the 25 year-old backup center, a clumsy-looking ex-auto mechanic named Mark Eaton, who is said to be 7'-4" and 290. Eaton kept improving as he aged into his height and eventually made the NBA All-Star game. But I don't recall anybody else on campus close to them in height.

Among whites, the median man 20-39 is 0.4" taller than the median man age 40-59 and 1.6" taller than the median man 60 or over (however, old people shrink).



Weight
Age 20-39 Males Females Diff
NH White 186 148 -20%
Black 190 171 -10%
Hispanic 176 155 -12%

People are weighed wearing disposable paper medical gowns.

At 148 pounds, younger white women average only 80% as heavy as younger white men, but black women weight 90% as much as their menfolk, so the male-female gap is only half as large among blacks. And Latinas weight 88% as much as Latinos.



Waist
Age 20-39 Males Females Diff
NH White 37.0 33.5 -9%
Black 36.4 36.8 1%
Hispanic 37.1 36.1 -3%

So, the median white man age 20-39 has a 37 inch waist, and the median younger white woman has a 33.5 inch waist, 9% smaller. (Pregnant women are excluded.) Among blacks, however, the typical younger woman has a wider waist than her male counterpart.



BMI
Age 20-39 Males Females Diff
NH White 26.4 24.5 -7%
Black 27.8 29.4 6%
Hispanic 27.7 27.7 0%

The oft-criticized Body Mass Index (BMI) reflects the same findings: whites are the skinniest, with black women considerably fatter than black men.

The total sample size who were subjected to quite a few measurements were an impressive 19,593, so subgroup sample sizes were quite adequate. (The smallest subgroup shown below numbered 361.)

My published articles are archived at iSteve.com -- Steve Sailer

39 comments:

jan said...

5'-10.4" = 164.7 cm ?
No wonder sometimes a spacecraft crashes...

Robert said...

In Egypt I noticed a dramatic difference in the heights of older and younger men, probably because of improvements in nutrition. Either that or there is a local perturbation in gravity.

RWF said...

"Among blacks, however, the typical younger woman has a wider waist than her male counterpart."

That's extraordinary. Is there any other population in the world where the women have larger waists than the men?

Anonymous said...

There's no such thing as race, you racist.

neon said...

It's sickening how fat Americans are.

John Mansfield said...

A friend told me the story of when he went to walk-on basketball try-outs at our college. A guy with a clipboard went down the line asking everyone's name and height, and everyone in front of my friend was adding two or three inches to their apparent height. When it was his turn, my friend said, "Well, I was only 6'2" when I walked in here." He got a bunch of dirty looks for that wisecrack.

jan said...

Steve, can you remove my comment since it makes no more sense since you corrected the mistake?

Kind Regards,

Jan

Ron Guhname said...

These results match those I reported from CDC data that Hispanics have a higher body mass than non-Hispanics. (I didn't separate whites and blacks). Mass immigration from the south is making us a fatter and less healthy country.

http://inductivist.blogspot.com/2008/10/hispanic-americans-are-fatter-than-rest.html

Anonymous said...

"Hispanic" is a misnomer. Really, we're talking about Spaniards and Aztecs.

In my experience, immigrants of Continental Spanish descent take umbrage at terms like "Hispanic" or "Latino." They always refer to themselves as Colombian, Cuban, etc.

--Senor Doug

Anonymous said...

It looks like NFL running backs are only average height. I compiled the combine measured heights, weights and 40 times for the top 30 rated players at each NFL position.

Running backs averaged 5-10.5, 223 w/a 4.51 40. (range: 5-6.1 to 6-4.2, 184-267; if you take Brandon Jacobs, who is a freak by himself out of the mix, the average drops to 5-10.3, 221 and the range drops to 5-6.1 to 6-1.5, 184-248).

For other positions, the averages are:

Safties: 5-11.9, 207, 4.51
Corberbacks: 5-11.0, 194, 4.46
MLBs: 6-1.0, 242, 4.67
OLBs: 6-2.1, 247, 4.64
DEs: 6-3.8, 276, 4.67
DTs: 6-3.0, 315, 5.11
C: 6-3.2, 307, 5.23
OG: 6-4.0, 311, 5.20
OT: 6-5.4, 321, 5.24
TEs: 6-3.8, 261, 4.74
WRs: 6-0.6, 204, 4.48
QBs: 6-3.3, 228, 4.86 (the shortest, and only one under 6' is 5-11.2 Jeff Garcia, Briese is 6-0.2)
FB: 5-11.9, 247, 4.74

They are some really big, really fast people.

As for height in basketball, I've noticed that around the basket, reach and length is really important and can be insurmountable. What drove this home to me was a Pros vs. Joes episode where the finalist was a very quick 5-7 gym teacher who had to play a half court 1 on 1 with an ex-NBA allstar (whose name escapes me) who was about 6'6. Both men were in their mid 30s. The gym teacher was much quicker than the NBA star and even managed to score a couple of baskets by out quicking him. However, the NBA player won handily because his 5-7 opponent could do nothing to defend him, he simply shot over him even though his position was perfect. It was also impossible for the5-7 guy to get a rebound even when he had better position. It just shows that even though the little fellow could move his body much more quickly and nimbly than an accomplished NBA 2 guard, the 11 inches in height were too much to overcome.

albertosaurus said...

In antropology this is termed sexual dimorphism. Man is usually said to have a value of 1.2 (your figures have whites at 1.25 and blacks at 1.11). Chimpanzees are 1.4 and gorillas and urangatans about 2.0. Gibbons are 1.0.

East asians as I remember have the lowest sexual dimorphism scores of all human races.

Sexual dimorphism is usually considered to be related to harems and sexual dominance. Gorilla males fight each other for access to the females. Gibbons don't.

I went to a very, very small college (250 total students). The tallest guy in the school was 6'7'. I was second tallest at 6'4". The tallest guy was the center on the basketball team and the president of the student government. I was the back up center and vice president. Height matters in politics too I guess.

Stopped Clock said...

I found data a few years ago that seemed to indicate that the current generation of Americans was shorter than their parents, especially among blacks:

http://halls.md/on/men-height-b.htm

Men don't hit their height peak at 37, so there's no possible explanation for that graph other than 1) bad data; or 2) people really are shrinking due to the increasingly bad diets we eat, despite all the emphasis on promoting health foods.

Duke said...

Your mention of the tallest man famous for non-height related reasons made me think of Abraham Lincoln. He was 6'4" and still ranks as the tallest Ppresident. By today's standards, he was somewhere between 2 and 3 S.D.s above the mean, but for his time (born around 1800), I'd guess he must've been closer to 4 S.D.s. I turned up some interesting information regarding presidential height on Wikipedia, and as it turns out, the easiest way to predict the winner of the presidential election is to choose the taller candidate. The taller candidate has one every election since 1900, with a couple of exceptions. All of this said, there appears to be a limit to this rule, otherwise our presidents would be as tall as NBA centers. That limit appears to be around 6'3" or 6'4". Above this height, does a person become too intimidating for the voter?

Anonymous said...

"bipolar" should be "bimodal"

Anonymous said...

Patrick Manning, a New York state assemblyman, is 6 foot 11. Not that famous, but maybe he qualifies. Former Reagan administration official and now pundit James Pinkerton is 6-9. And I seem to recall there was a 6-11 Washington official in the late 1970s or 1980s who was arrested for spousal abuse.

Bill said...

I've known a lot of very tall guys. Two at 6'9", one 7', and quite a few around 6'6"-6'7". One thing that struck me about most of them was their lack of strength relative to size. Some of them played basketball, but none was very good.

One funny thing about the seven footer was that he had relatively short legs for his height. This guy had an amazingly long trunk. His lungs were so huge that when he smoked a cigarette it was burned to the butt in half the time it took others to finish.

Anonymous said...

"The standard deviation for white males appears to be a little more than 2 1/4th inches and for other males around 2 1/2 inches."

how did you come up with this?

Anonymous said...

John Fedders, former director of enforcement for the Securities and Exchange Commission in the 1980s, was 6-10. And a wife beater.

rob1 said...

It's a mistake to think people have been getting taller and taller down through the centuries. Humans as a species have probably reached maximum height. No records have been broken in this field for well over a century, despite improvements in nutrition.
The tallest non-pathological giant on record, the 7ft10in Scotsman Angus MacAskill, died in 1863.
Large-sample skeleton measurements have shown that the average height of an English man in the year 1000 was 5ft8in, only about an inch shorter than today. English people were at their shortest in the Victorian era.

Sgt. Joe Friday said...

And check out the median for Hispanic women: just under 5'3" and 155 lbs. In other words, short, squat, and with a waddling gait. You see lots of them around southern California, usually with 3 or 4 ninos and ninas in tow.

Another reason to build that fence. It'll cut down down on eye pollution.

jody said...

there is no such thing as a "hispanic" as used here. the data is confounded, and any analysis performed on the numbers for "hispanics" is just plain wrong.

it makes no sense at all to confound the data by identifying all humans by their race, except if they speak one particular language, then, every speaker of that language somehow becomes part of a new, fake race.

steve really, really needs to stop using "hispanic" as it is used by the US census bureau. this term is wildly wrong and inaccurate, and cannot possibly be used for any kind of academic study or analysis. they are confounded from the start, and conclusion is invalid.

the CIA is the only US government agency that correctly identifies people by their race. every other agency, even the FBI, gets it totally wrong. in fact, the data for "blacks" is probably most accurate, as generally few people are incorrectly put into that group.

i mean this is really easy stuff. all hispanics are white, and their data goes in the "white" category. if you are not white, you are not hispanic. period. i don't get what is so hard about this. people implicitly understand this about anglo-saxons, about slavs, about scandinavians. for an academic doing academic stuff, this is elementary. does steve not understand that this data is confounded from the start by putting europeans, africans, and american indians all in the same category?

american indians from mexico and central america are short, fat, and brown. HISPANICS, white guys from spain, are taller and slimmer. perhaps this will explain to steve why some spaniards are able to play soccer, basketball, and tennis at the highest level, while mexicans usually can't. but i doubt it. steve sticks to a strict script. all humans with a spanish name are the same race.

if steve compared the average height in 10 "hispanic" nations, i wonder if he would be able to explain why some were taller than the others. i mean, he mainly writes about race, but he gets this detail SO WRONG, i literally wonder if he would understand why "hispanics" in argentina are taller than "hispanics" in guatemala. is he puzzled by somebody like walter herrmann, a german guy from argentina who plays basketball for the detroit pistons? does he think walter herrmann is the same race as hector ruiz, a descendant of mayan indians who flips burgers at the local in-n-out?

ben tillman said...

John Fedders, former director of enforcement for the Securities and Exchange Commission in the 1980s, was 6-10. And a wife beater.

That calls to mind a local 6'8" bankruptcy attorney. He was busted for insider trading (or something like that), and he played basketball at Vandy, so you can get all kinds of info on him by googling his name plus "SEC".

Peter said...

Black men come out pretty good on this survey, with their smaller waists as compared to white and Hispanic men. Waist measurement is probably the single most important numerical indicator of fitness and health in men.

Anonymous said...


"English people were at their shortest in the Victorian era."

Why? If that's true, I'm not coming up with any plausible explanations for it. I'm not saying it's not true, just weird. rob1, where did you get that info?

Anonymous said...

Why? If that's true, I'm not coming up with any plausible explanations for it. I'm not saying it's not true, just weird. rob1, where did you get that info?


Because during the early industrial revolution the health of the lower class declined precipitously. Workers lived in more cramped disease ridden conditions with worse nutrition than their immediate peasant ancestors.

Anonymous said...

Isn't Paul Volcker freakishly tall even though he apparently has some Jewish ancestry? So is Brad Garrett, Ray Romano's sitcom brother on that show Everybody Loves Raymond.

I've always been confounded by very tall Jews or half-Jews - it doesn't make sense...Jews just don't get very tall unless they have recent non-Jewish ancestry (especially from Northern Europe) coupled with very good nutrition. Or they have a pituitary disorder.

The Ultra Orthodox Hasidics and other groups are especially known for their shortness and slightness.

SKT said...

"american indians from mexico and central america are short, fat, and brown. HISPANICS, white guys from spain, are taller and slimmer. perhaps this will explain to steve why some spaniards are able to play soccer, basketball, and tennis at the highest level, while mexicans usually can't. but i doubt it. steve sticks to a strict script. all humans with a spanish name are the same race."

Perhaps, but the greatest player of the world's most popular and competitive sport, soccer, was pure American Indian Maradona from Argentina.

Hugh Oxford said...

The taller candidate has one every election since 1900, with a couple of exceptions. All of this said, there appears to be a limit to this rule, otherwise our presidents would be as tall as NBA centers.

It's interesting that in America of all places, arguably the birthplace of modern meritocracy, height discrimination is still a tangible reality. I think it's fair to say that the better man has often been denied his rightful place because of it, and America has been a poorer country as a result.

The left, of course, aren't that interested in fighting height discrimination, even when you point out that stature is a greater determinant of salary and organizational status than sex.

When I went on national TV and radio a few years ago in the UK to raise awareness about height discrimination, the absence of concern from certain left wing elements was quite noticeable.

That's because their fights for equality are rarely that, and are more complex psychological and ideological expressions. Some inequalities are more equal than others.

albertosaurus said...

You keep repeating the mistake that the tallest man famous for something other than height was Chrichton or Galbraith.

Again I point out the well documented (if possibly erroneous) eight and a half foot staure of third century Roman emperor Maximinus Thrax.

There are typically a few eight footers on earth in each generation. There are hundreds of thousands of seven footers and millions of guys as tall as Chrichton.

Is the US Congress an accomplishment? Tom McMillen was 6'11".

Blode032222 said...

Black men come out pretty good on this survey, with their smaller waists as compared to white and Hispanic men. - Peter

This is true, but it's important to note that, according to according to Steve black men need to maintain a lower body fat percentage (12%) than white men (15%) or Asian men (18%). The kinds of things that set in when you are too fat include hypertension, a type of diabetes, etc. .. and those things hit thinner black guys than whites or Asians.

If I may quote our host, it just shows that "let the good times roll" is an especially risky message for blacks. This will continue to be true until North America's conception of "good times" stops including snack cakes, corn chips, fried chicken, and marbled beef. And especially soda! So while Asians may be more resistant to fast food culture (I certainly don't see them at Cinnabon very often) they are probably more likely to be able to survive it, given their thousands of years' exposure to white rice.

@ Jody - You've said a lot there, and there are good points. Can you direct me to anything by the CIA on this subject? I didn't know they did any stats on US citizens, least not publicly.

I believe Steve is using the lumper's "Hispanic" terminology because that's all he's got. "Hispanic" may be a silly North American invention but it's matched south of the border by "La Raza". I can't see any way for him to split this category statistically; you dance with the stats that came to the dance.

Anonymous said...


Because during the early industrial revolution the health of the lower class declined precipitously.

However, famines in Europe disappeared during and because of the Industrial Revolution. The Irish potato famine of the 1840s and the Russian famines that were occurring right until the 1930s happened in pre-industrial economies.

rob1 wrote "English people were at their shortest in the Victorian era." Well, there were no famines in England during the Victorian era, only in Ireland. And up until the 18th century there were regular famines in England, as in any part of Europe or of the world at large. So I'm unconvinced. Either the data that rob1 cited is wrong or it has an explanation of which I am ignorant.

Also, the person who called Diego Maradona (the world's most popular athlete of the 1980s) a pure Indian was wrong. Maradona is a mestizo. It's really amazing that such a short and pudgy guy could do so much in such a physical sport. Not any sort of an intellectual either, so you can't ascribe his success to smarts. I guess he just wanted it more than others.

Stopped Clock said...

Modern Europeans still have not approached the average height attained by the Cro-Magnons, which was about 6'5" for men and probably about 6 feet for women. This maximum value occurred so far back in history, however, that it seems likely that the actual genetics of our people have changed. Cro-Magnons lived on a primitive but very proteinaceous diet; and there weren't many of them, so they probably didn't experience famines often. But I'm speculating.

Natural Athlete said...

Stopped clock I have no idea were you got those figures. I have yet to read about a famous upper paleolithic specimen that even reached that height. The old man of cro-magnon himself was orginal estimated at 190 centimeters 6^3 and thought to be very tall for his time later estimates dropped him down to much less impressive 166 centimeters. The grimaldi skeletons were 177 centimeters on average. I have seen the figures of 5^10 and even six feet thrown about for upper paleolithic modern humans but with no real support and the best figures I can find indicate a height of closer 5^8.

I love seeing this sort of anthropometric Data its real shame that it isn't more regularly studied lots of enlightening information available through it study if people could get over their fear of the concept of race.

This provides some interesting looks into genetic differences but its hard to parse them out due to the confounding factors of poverty, and obesity.

The mess of category of hispanic probably certainly averages out as look at central american amerindian mixed group. These people are genetical inclined to short stature but many, many of them also come from malnourished backgrounds and second and third generations imigrants are significant taller then first generation so what is genetic and what is poverty.

Likewise with waist size all americans are fat, I am 6^2 and 200 with larger then average frame and my waist is 33, 37 at 5^10 is huge. I also not that while we have grown .6 inches in the last generations remember seeing statistics of average weight as being 175 a generation ago so thats an 11 pound weight gain in a generations thats frightening.

There's interesting stuff going on at the tails, Hispanics have a real slim tail on bottom end of the waist size indicating the seem to be naturally thicker in the abdomenon even without excess fat. While blacks have fat tails on both sides of the height and waist distribution which would seem to indicate they're overall greater genetic diversity. My observations would seem to indicate that healthy male blacks have smaller waists significantly with distinct wasp waisted look and the fat tail on the other side is correlated with poverty related obesity.
Black women seem to have relatively more robust and powerful frames on average, I read a study recently that indicated the in west africa the preference for WHR in women was 80% as opposed to the 70% common in europeans and asians so part of the their greater waist size may be genetic even while poverty must be huge factor.


Really interesting stuff its to bad there is not more in depth data.

VoodooMan said...

Hugh Oxford:
It's interesting that in America of all places, arguably the birthplace of modern meritocracy, height discrimination is still a tangible reality.

Heightism is largely an upper-class Anglo-Saxon thing. You don't (or at least I didn't) see as much of it in Italian, Hispanic, or even poor Anglo communities.

The left, of course, aren't that interested in fighting height discrimination, even when you point out that stature is a greater determinant of salary and organizational status than sex.

The modern Left is also reluctant to champion disabled people, particularly those physically disabled. I actually heard a leftoid dismiss wheelchair access as a "white issue" - as if non-races are so much more mighty-thewed. There may well be a hidden social-darwinist double standard here.

Blode032222 said...

Call me ignorant, but how would one fight height discrimination? I can't think of a way to do it politically, except for with [blechkh!!] affirmative action. Then again you could also use moral suasion / civic action / etc. That I would be fine with.

As a tallish person (6'1"), I always feel like people ignore me in person about as much as they do online, so this issue is pretty orthogonal to me. :)

Hugh Oxford said...

The modern Left is also reluctant to champion disabled people, particularly those physically disabled.

That's because they want to kill them before they're born. They don't want them to even exist.

Stopped Clock said...

I am at the 2nd percentile for adult white male height, that is, about 5'6". I think I've been on both sides of the discrimination equation because of my height.

Once I worked for a boss who was an immigrant from Egypt and even shorter than me, and I noticed that he seemed to like to work with me because I was the only employee who could stand next to him to look at paperwork, etc without obstructing his view of the rest of the room. He seemed more comfortable talking to me than to the other employees and once said that wanted to promote me to a supervisory position, perhaps so I could be his go-between, but I told him I was moving in a few months and couldn't stay.

On the other hand, I've worked manual labor jobs where I work with men who are generally much taller than me and find that the managers usually give me tedious jobs that don't involve muscle strength, even though I've shown that I'm just as strong as most of the other workers.

I've never really gotten into the world of white collar office work, so I can't say whether height discrimination plays any real role there ... and that's what most of the allegations of discrimination seem to be about. In general I'm skeptical, since I don't believe discrimination is the root cause of the racial wealth gap or the male/female wealth gap either.

Regarding Cro-Magnon height: were the Grimaldi skeletons all male? In either case, I could be wrong; I'll check up on the hard data later.

VoodooMan said...

There's really no way to fight height discrimination; and I was not suggesting that government should be doing that. I was merely suggesting that liberals and leftoids could be less hypocritical regarding their choice of downtrodden underdogs.

Strangely enough, the world of white-collar / urban professional office work has some of the most atavistic prejudices imaginable - but none of these involve race, so the liberals are happy.

My own experiences were the opposite of Stopped Clock; in that blue-collar adult environments were fairer, and more based on talent than superficial image. Life is not a Hollywood beauty contest - but try telling that to some so-called professionals.

Anonymous said...

"I'd guess he (Abraham Lincoln) must've been closer to 4 S.D.s."

The average white American man born in the 1st half of the 19th Century was 5'8.25". Working on a 2.5" S.D., he was 3.1 S.D.s above average. Assuming a 2.25" S.D. (which I doubt because nutrition would have been more unequal then, causing increased non-genetic variance), 3.44 S.D.s.

"I've known a lot of very tall guys. Two at 6'9", one 7', and quite a few around 6'6"-6'7". One thing that struck me about most of them was their lack of strength relative to size."

That's simple physics. The contraction power of a muscle increases proportional to its cross sectional area perpendicular to the axis of contraction, whereas weight increases as a function of volume (i.e., as you get proportionally bigger, strength goes up squared and weight cubed so power to weight ratio drops). E.g., if you were twice as tall and breadth and depth increased proportionately, you would be 4 times stronger and eight times heavier (and would probably collapse under your own weight). If you were simply to get taller/more elongated without getting broader/stockier your weight would go up linearly (as only one dimension is increasing) and your strength would not go up at all. This is why smaller athletes can do everthing proportionally better than larger ones. E.g., take Usain Bolt and Maurice Greene. Bolt has a faster 100m time (9.69 vs. 9.79) and is taller (1.96m vs. 1.75m). 100m is 51.02 times Bolt's body length and 57.14 times Greene's body length. If Greene keeps a constant pace to his 100m time, he can run 51.02 times his body length (89.3m) in 8.74s. Hence, relative to his size, Greene is much faster than Bolt, but Bolt edges him out in absolute terms.) Larger athletes, however, often have an advantage in absolute performance until they become so large that they reach a break point (which varies depending on the sport and position) where they become so underpowered that they can no longer take advantage of their larger frames.

"So I'm unconvinced. Either the data that rob1 cited is wrong or it has an explanation of which I am ignorant."

The later is the case. Height declined in Late Medieval/Early modern Europe for several reasons: Climate (The mini-Ice Age) deteriorated, reducing agricultural yields as population was increasing, so nutrition deteriorated. Also, populations became increasingly urbanized, which further impacted nutrition because it was difficult to get enough fresh food into the cities with the given transportation methods available. Also, large cities, with their high population density, constant streams of visitors from different regions, and poor sanitation meant that the disease load on people became much heavier, which impacted growth.

For data on historical heights, see here:
http://web.econ.ohio-state.edu/rsteckel/VITA/2003%20New%20Light%20on%20the%20Dark%20Ages.pdf

http://www.eco.rug.nl/medewerk/jacobs/jjdownload/Workshop14May-Koepke.pdf

http://www.sirguillaume.com/Downloads/Old_Age-Height-Nutrition.pdf

"Modern Europeans still have not approached the average height attained by the Cro-Magnons, which was about 6'5" for men and probably about 6 feet for women. This maximum value occurred so far back in history, however, that it seems likely that the actual genetics of our people have changed."

Rubbish. Upper paleolithic European males appear to have been about roughly modern stature (179cm/5'10.5") and slim (67kg/147lbs.) while the females were small and robust (158cm/5'2" and 54kg/119lbs). They had proportionately longer limbs with elongated distal segments than modern Europeans (more like modern africans) so they seem to have genetically caused differences in body build.

http://hormones.gr/pdf/Stature_europeans.pdf