Netflix's tell-all docuseries about The Biggest Loser featured interviews with former contestants, trainer Bob Harper and more people associated with the show - but was Jillian Michaels involved? During the third part of Fit for TV: The Reality of the Biggest Loser, which premiered on Friday, August 15, the docuseries featured a message that read, "Jillian Michaels declined to participate in this documentary." (Michaels, 51, was mentioned in all three parts and archive footage of her and Harper was used throughout.