Transcript for Olympics 2012: Evolution of US Athletes
and a 30-tablet free trial. As we said, the london olympic games are under way. There are 530 men and women on team usa. Many of them have spent almost their entire lives preparing for this one moment. That's not unusual for olympic competitors, this year's athletes are bigger, stronger, faster, than the americans who came before them. Why is that? Jeffrey kofman in london tonight on the evolution of the american olympian. They are the gold standard of athletic excellence with muscles toned and movements honed, they're the fittest and finest of the worth's athletes. Go back a few decades and it's not just the funny outfits that are different. So are the athletes' bodies. The physique from charles in 1920 and watt field in 1948 to muscular david wolths in 1972. There is tiny korbut, the russian gymnast who awed the world in 1976. Here is team usa's jordyn wieber, a mass of muscles. Mark spits, who won seven gold medals in 1972. You recognize michael phelps. The shoulders, it's all changed very recently. Just asked judy who captained team usa to two gold medals in soccer. My last olympics was in 2004. We were just getting into, hey, strap on a heart rate monitor. That's really cool, we can check our heart rate. Now if I was playing, they have wires on them, plaits on them, they're doing treadmill tests. Reporter: To grab that gold, athletes do things that would have been unthinkable, rigorous discipline and an exploding field of sports science. The dissection of movement. We know gold medal sprinters are taller and bulkier. Marathoners, smaller and leaner. Talent still drives the bus. But you got to remember we're in a sport where a 1% difference is the difference between a gold medal and not making the final. The olympics of old, athletes were born competitors, today they get a little extra help. Now I feel hessly inadequate.
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