Jillian Michaels and Bob Harper – longtime trainers on “The Biggest Loser" – appeared inseparable on screen, but behind the scenes their friendship fell apart.

After Biggest Loser alum Bob Harper called out Jillian Michaels for not checking in on him following his 2017 heart attack, Jillian reacted to his comments.

Since the documentary aired, cracks have also begun to show between the show's familiar faces, including Jillian Michaels, and fellow trainer, Bob Harper. During The Biggest Loser's hay day, while ...

Season 15 winner Rachel Frederickson lost nearly 60% of her body weight, shocking viewers and health experts at the time. Fit ...