'The Biggest Loser' winner Rachel Frederickson dropped 155 pounds and it was not without controversy.

When she revealed her new, slim frame on the show's Feb. 4 finale, trainers Bob Harper and Jillian Michaels could not hide their shock over her transformation. Now, Harper is speaking out about his visibly bowled-over response.

Harper taped an appearance on 'The Rachael Ray Show,' which will air on Feb. 13, explaining his extreme reaction to, well, an extreme body change for Frederickson, which had fans and critics questioning what such a drastic weight loss could mean for the contestant's health.

He explained (quotes via Us Weekly) that his reaction was genuine because he had not seen Frederickson in quite some time.

"What people don't understand is, when the contestants leave to go home ... they're in charge of themselves," Harper reasoned. "I had not seen her until that night, and so when she walked out, I was just kind of like, 'Whoa.' And I've been on the show since the beginning, forever."

Harper admitted he was "stunned," although he didn't need to, since his face pretty much revealed exactly how he was feeling. "I mean, we've never had a contestant at 105 pounds," he said.

Harper and Michaels declined to specifically comment on Frederickson, since they were not her actual trainers. That role was occupied by Dolvett Quince. They did make statements on Facebook, which read:

We're not comfortable commenting on Rachel's journey because we weren't her trainers and weren't given an opportunity to work with her at any point. Any questions about contestants on 'The Biggest Loser' should be directed to the show's producers.

Quince himself commented, saying,"'Biggest Loser' is a journey which has its ups and downs. Please try not to look at one slice of Rachel's journey and come to broad conclusions. Rachel's health is and always has been my main concern and her journey to good health has not yet ended!!"

So, basically, the trainers are saying that Frederick's weight loss was, and is, a journey not a destination.

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