Are athletes really getting better, faster, stronger?

A new TED talk by David Epstein says “not as much as you might think.”

From the transcript, here is one interesting excerpt:

…consider that Usain Bolt started by propelling himself out of blocks down a specially fabricated carpet designed to allow him to travel as fast as humanly possible. Jesse Owens, on the other hand, ran on cinders, the ash from burnt wood, and that soft surface stole far more energy from his legs as he ran. Rather than blocks, Jesse Owens had a gardening trowel that he had to use to dig holes in the cinders to start from.Biomechanical analysis of the speed of Owens’ joints shows that had been running on the same surface as Bolt, he wouldn’t have been 14 feet behind, he would have been within one stride.

This is interesting too:

In the early half of the 20th century, physical education instructors and coaches had the idea that the average body type was the best for all athletic endeavors: medium height, medium weight, no matter the sport.And this showed in athletes’ bodies. In the 1920s, the average elite high-jumper and average elite shot-putter were the same exact size. But as that idea started to fade away, as sports scientists and coaches realized that rather than the average body type, you want highly specialized bodies that fit into certain athletic niches, a form of artificial selection took place, a self-sorting for bodies that fit certain sports, and athletes’ bodies became more different from one another. Today, rather than the same size as the average elite high jumper, the average elite shot-putter is two and a half inches taller and 130 pounds heavier. And this happened throughout the sports world.

There is this contrast:

… if you know an American man between the ages of 20 and 40 who is at least seven feet tall, there’s a 17 percent chance he’s in the NBA right now…in sports where diminutive stature is an advantage, the small athletes got smaller. The average elite female gymnast shrunk from 5’3″ to 4’9″ on average over the last 30 years, all the better for their power-to-weight ratio and for spinning in the air.

I cannot say I am convinced, if only because I don’t recall too many NBA players from my boyhood looking like Charles Oakley.  You can suggest that example more than fits the author’s hypothesis, but then I wonder which view he is arguing against.  If you hold enough other things equal, of course performance has to be equal too.

For the pointer I thank Mitch Berkson.