I guess I'm most disturbed by the quote from the producer that the contestatns did better than they expected, which of course means they anticipated some participants would face extreme pain and possibly severe injuries.
There's a huge moral dilemma in these shows, in that the producers are motivated by the income generated. The more dangerous and painful to the participants, the better television it is.
And on the other hand, people have the right and responsibility to make their own decision about participating. Some of the trainers and physicians hired by the show may believe that they're helping, but unlike the "real" world, they're not being paid by their clients, they're being paid by the show. That's a huge potential conflict of interest in that they're getting paid quite a bit to do what's best for the show, not the participants.
As long as you don't have any delusions that the producers are out to actually help anybody, and the show is entertainment only (don't try this at home and all that junk), I guess it doesn't bother me any more than other "unscripted" shows. I say unscripted rather than "reality" show because most of these shows do not reflect reality in any significant way.