Interesting topic and reminded me of a topic in a "Sports in Society" class at SEMO. The topic one day was "Why do so many major sports have a disproportionate number of black athletes compared to the % of blacks in the general population?"
Note: The old tale that blacks have an extra muscle in their legs is a myth. Blacks and white are identical anatomically.
These were the theories introduced, and are just theories;
Genetic theory: Slave owners wanted strong and healthy slaves for workers. Often slaves who were not physically fit, disabled, born with defects, not big and strong, and not valuable workers were castrated and even killed at birth. The healthiest were encouraged to pro create, while the less than desirable slave were prohibited. Thus the gene pool among blacks favor big, strong, muscular, physically fit offspring.
Economic theory: Dating back to the days of segregation and racial discrimination, sports were the first real opportunity for blacks to make a lot of money. For most of our history through emancipation, Jim Crow, and the Civil Rights movement, blacks did not have the opportunity in business to become rich. But blacks did see athletes like Jack Johnson, Joe Lewis, Jackie Robinson, and eventually the inclusion of blacks in all sports become rich.
Social theory: As a result of blacks inclusion in professional sports, blacks began to see sports as their only path to becoming wealthy. For much of black's history, they could not even get into college to become doctors, lawyers, bankers, and big businessmen. As a result, blacks began to focus more on becoming athletes and worked harder to become highly skilled, with the hopes and dreams of becoming rich. Sports such as basketball and football became a part of the black culture. Blacks took to team sports that could be played for free or cheaply, and not the "country club" sports. Still today, the quickest and easiest way for a great many blacks to escape poverty is through sports.
I tend to believe it is a combination of all 3 theories.
