RM, you said,

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"For years, racists have had a field day using bogus studies to describe changes in bone density and buoyancy in blacks to explain the differences in swimming ability. Racists need something to latch onto to feel superior."
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And you're absolutely right. If you'll notice, the fanatical preoccupation with the abilities of Black people is a fixation that seems to be exclusively dwelled upon by bigots.  There's a very simple reason for that, and you touched on it in your article. They're insecure, and when they come across the many Black people who are superior to themselves in life's various endeavors, they see it as a direct assault on their personal self-esteem.  That's why I asked you not to intervene on my behalf with the trolls on my wall.  Soaking up the agony of their insecurities is one of  the great joys of my life, and when you refocus their thinking in a way that forces them to try to justify their ridiculous propositions, it dilutes the purity of their agony, and thus, my joy, because it sends them into deception mode.  I enjoy feeling the full furry of their angst, because I know that for a bigot, suffering a sense of intellectual inadequacy in the face of a Black man is more painful than if I shot him.  In addition, he's denied the luxury death. It's something that he has to live with for the rest of his life.  So in their racist mentality, they've created their own Hell.
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Racists tend to be the mediocrity of White society, so they try to use the fact that they were born White to define themselves and to compensate for their lack of personal value. Their entire sense of self-esteem is based more upon group association than individual value and accomplishment, and their entire claim to personal significance is, "Well, at least I'm better than them." 
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That's what's driving radical conservatives so crazy about President Obama - he's walking, breathing, evidence that they cannot claim superiority by virtue of the color T-shirt they were born in, and that simple fact alone is causing them to suffer a severe attack of cognitive dissonance before the eyes of the entire world. That's also why they're so determined not to allow President Obama to be successful, even if it means destroying the country - and international corporatists are using the social division inherent in those sentiments to lower the standard of living of the American middle class.  
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Thus, this entire nation, and the future of our children, is being threatened by the desperate attempt of a handful of insecure bigots to maintain their delusions of superiority, and as far as they’re concerned, if the country has to be sacrificed for that cause, so be it.

Unfortunately, there aren't nearly as many public swimming pools as you might think, and the numbers are dwindling. Community pools are in trouble, and that affects people of all ages and races - but kids most importantly. Learning to swim is a life saving tool most effectively taught in a controlled body of water; without free access to a swimming pool it likely won't be achieved. The "free" aspect is essential for inner-city and low income kids, and that does create a racial disparity.

From the above link:

And finally, perhaps the greatest reason saving community pools matters so much to so many is they teach a vital skill. As opposed to say, public tennis courts, a public pool provides the setting for learning a potentially life-saving skill. As the well-known African-American swimmer Sabir Muhammad once told an ESPN reporter, "No one dies from not being able to play basketball."

Eadweard Muybridge, groundbreaking photograpic & kaleidiscopic studies of the human body as well as animals in motion, 1887 and thereabouts.

Here are "Racists" at Howard University using "bogus studies" to back the "myth" that blacks don't have the right bodies for swimming (but do for other sports - I was watching marathon runners yesterday & horn-of-Africa runners seem quite different from usual American body types) - even as USA Swimming explores other cultural & demographic factors:

Twenty-eight of the last 38 world record holders in the men's 100-meter dash have been black athletes, and researchers at two universities think they know why.

A new study by researchers at Howard University, a historically black school in Washington D.C., and Duke University in North Carolina suggests why black athletes may outperform athletes of other races in running events. Physical differences in the length of the limbs and the structure of the body mean the center of gravity tends to be higher in the bodies of black people, the researchers say.

Since 1968, the world record holders in the men's 100-meter dash have been black athletes. And since 1912, when the International Association of Athletics Federations started keeping track of the record holders in that event, only 10 non-black athletes out of 38 individuals have held the title.

"There is a whole body of evidence showing that there are distinct differences in body types among blacks and whites," said researcher Edward Jones, who researches adolescent obesity, nutrition and body composition at Howard University. "These are real patterns being described here. Whether the fastest sprinters are Jamaican, African or Canadian, most of them can be traced back generally to Western Africa."

Why center of gravity matters

Although there are also cultural factors at work, it all comes down to body makeup, Jones said.

"Blacks tend to have longer limbs with smaller circumferences, meaning that their centers of gravity are higher compared to whites of the same height," said Adrian Bejan, Jones' co-author, an engineering professor at Duke University. "Asians and whites tend to have longer torsos, so their centers of gravity are lower."

"These differences are small, and we don't really see them when we look at someone," Bejan told Life's Little Mysteries. "We are only rarely struck by how long someone's legs are."

But these small differences certainly matter in races lasting less than 10 seconds, Bejan said.

The height of a person's center of gravity affects how fast his feet are moving when they hit the ground, Bejan said. Each step a runner takes is like falling except the athlete breaks the fall with his foot. So the feet of a person with a higher center of gravity will hit the ground faster than someone with a lower center of gravity.

Torsos and legs

In the study, the scientists gathered data available from the militaries of 17 nations. Militaries measure their recruits for uniform fittings and are a reliable source of data, Bejan said. To approximate torso length, the scientists compared the average height of the military men with their sitting height – the distance from a chair to the top of the head.

Results showed the average sitting height of blacks was about 1.5 inches (3 cm) shorter than that of whites who were the same height. This means that, among blacks and whites of the same height, the legs of blacks were longer (think of a high-waisted person), while the torsos of whites were longer.

This physical difference gives a black athlete an advantage, even against an athlete of another race is who is taller and has a higher center of gravity, said Bejan. From a physics perspective, Bejan said, the legs do the work of running and the torso of the body is just extra weight that the legs must carry, so the race goes to the runners with longer legs and shorter torsos.

By contrast, whites tend to have the advantage in swimming, where a longer torso allows for faster speeds.

"Swimming actually generates a wave. The sport is the art of surfacing on that wave. When the wave is bigger – because the torso is longer – they go faster," Bejan said.

The study was published online this week in the International Journal of Design and Nature and Ecodynamics.

Bonus: The Ideal Swimmer's Body, Ideal Body Types for Different Sports, Your "Ape Index" and How It Affects Your Swimming (ratio of arms to body length) from SwimSmooth. "It's [sports success] about 55:45, genes to environment," says Mike Rennie, professor of clinical physiology at the University of Nottingham Medical School in Derby, as he notes"In swimming, only 5-10% of the propulsive force comes from the legs, so technique is vital." To illustrate his point, he cites triathletes, who are all extraordinarily fit, yet who may fail to reach competition standard if their swimming technique is poor. "

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The Scientific Theory [note: the first half goes into the Cultural Theory - fear, access to pools, peer habits, etc.] Here is original Duke University article on joint Duke/Cornell study.

The human body is amazing.  Despite all of our cultural differences, us humans are roughly the same.  Studies show that intergenic DNA, (around 70% of our DNA) has no apparent function.  Genes are around 5%.  Around 99.8% of the DNA sequence in all humans is identical.  That leaves a small margin for major differences.

But certain studies claim that that small margin has a large affect.  Prior to writing this, my father showed me a study that he had stumbled across that clearly explained concept of the centre of gravity of the human body.  The centre of gravity, believe it or not, is found in the length of the torso.  Duke’s Pratt School of Engineering’s Professor Adrian Bejan has formulated a theory that may be of great aid to solving the conundrum.

Professor Bejan, along with Ph.D. candidate Edward Jones, Jordan Charles believe in a theory states that athletic success–and failure–lies in the center of gravity.  The longer the torso, the lower the center of gravity.  The lower the center of gravity, the larger wave one makes.  Read what Jones had to say:

There is a whole body of evidence showing that there are distinct differences in body types among blacks and whites.  These are real patterns being described here — whether the fastest sprinters are Jamaican, African or Canadian — most of them can be traced back generally to Western Africa.  Swimmers tend to come from Europe, and therefore tend to be white.

Jones and Bejan agreed that it is not necessarily linked directly to race, rather, it is linked to anatomy.  They said:

Blacks tend to have longer limbs with smaller circumferences, meaning that their centers of gravity are higher compared to whites of the same height.  Asians and whites tend to have longer torsos, so their centers of gravity are lower.

The centre of gravity is three percent higher in blacks than in whites.  As a matter of fact, many measurements show that a black men have a higher centre of gravity than white men of the same height.

According to Bejan,

“Locomotion is essentially a continual process of falling forward. Body mass falls forward, then rises again. Mass that falls from a higher altitude falls faster. In running, the altitude is set by the location of the center of gravity. For the fastest swimmers, longer torsos allow the body to fall forward farther, riding the larger and faster wave.”

Still, there have been numerous studies about the bone densities and buoyancy of either race.  According to the American Journal of Human Human Biology, an experiment was conducted studying the buoyancy of thirteen black males and thirteen white males.  They were matched for age, weight, and height.  In a swimming pool, they were tested for vertical and horizontal buoyancy.  Similarities were found in the breathing patterns of both races, eliminating the notion that the black swimmers were afraid of sinking, thus affecting the ability to float.

The main difference was this: the whites had significantly higher fat distribution; the more fat, the more buoyancy.

As for the bone densities, Edward Jones stated something that should ring a bell: black women have a lower incidence of osteoporosis than white women because of the increased density of their bones.  The Journal of Clinical Endocrinology and Metabolism stated that at certain skeletal areas, bone density is 4.5–16.1% higher for black than for white men and was 1.2–7.3% higher for black women than for white women.