Read this New York Times article by Buzz Bissinger. Plain and simple: in order for the girls (not women: the average age of this year's US team, for instance, is only 17 and a half) to develop skills necessary to compete at the Olympic level, they can have no childhood, only grueling and rigorous years of training. And of course, the decision to undertake this training is, by definition, not a decision made by the athlete as an independent adult, it is a decision made for them by her parents. The effects of such nightmarish training on these girls' bodies, their development both emotional and physical, would be bad enough by itself, but the odor of worse abuse attaches itself to the intense relationships coaches develop with these girls. Bissinger points out several examples of sexual abuse pre-teen gymnasts have suffered at the hands of their coaches, and while such cases are surely a small minority, the demanding/dependant relationship between coaches and the young girls is psychologically damaging in any event.
The Romans enjoyed gladiatorial combat to the death, and while the abuse suffered by female gymnasts isn't quite so extreme, at least the Romans didn't kid themselves as to the source of their enjoyment or the suffering of its victims.