The newest round of contestants on The Biggest Loser are the biggest ones yet. This season, which premieres tonight on NBC, will feature one contestant who weighs in at 526 pounds, a size that the show’s trainer, Jillian Michaels, is worried about.

"The contestants keep getting bigger and bigger," she told Ladies' Home Journal. "As the trainers we have no say over the challenges. We worry about them too."

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Despite a woman passing out from heat stroke during a one-mile run last season, the show will go on, said producers.

"We all worry," said executive producer Todd A. Nelson, adding that the show is learning how to safely manage the medical conditions of the heaviest contestants, "and this allows us to fine-tune the process and reach out to a heavier population." Go to PopEater for more on this story. (PopEater)

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