For years, Bob Harper and Jillian Michaels appeared to have great chemistry onscreen while filming “The Biggest Loser” together. But a new docuseries about the NBC weight-loss competition has fans wondering if the dynamic duo actually got along in real life.
“Fit for TV: The Reality of the Biggest Loser” takes a look back at the wildly popular series, which aired on NBC for 17 seasons.
The three-part docuseries features interviews from former contestants and hosts of the show, including Harper. Michaels, meanwhile, declined to participate in the project.
Harper’s comments about his former co-star have many fans buzzing about the status of their relationship. Below, we’re breaking down all the essential info.
How Long Did Bob Harper and Jillian Michaels Work Together on ‘The Biggest Loser?’
“The Biggest Loser” aired on NBC between 2004 and 2016, per IMDB. It was later rebooted for one season on USA Network in 2020.
Michaels appeared in 183 episodes of the show between 2005 and 2014, per IMDB, while Harper appeared in 251 episodes between 2005 and 2020.
During their tenures on the show, Harper and Michaels competed against each other as personal trainers working with contestants.
What Has Harper Said About His Relationship with Michaels?
In 2020, Harper told Us Weekly that he and Michaels had not been in touch with each other “at all” for quite some time since they’d worked together on “The Biggest Loser.”
While appearing in the Netflix docuseries โFit for TV: The Reality of the Biggest Loser,โ Harper addressed the heart attack he sustained in 2017.
โIt was one of the hardest things Iโve ever gone through. I was dead on the gym floor for nine minutes,โ he said.
While referencing his former co-star Michaels, Harper said she did not reach out after his health scare.
โHow do I put this? People were always like โYou and Jillian have been so closeโ, and I was like โWell, we were really close on television,โโ he said. โAfter I had my heart attack, sheโs the one person I never heard from. So, I mean, that to me spoke volumes.โ
During an interview with The Guardian in August 2025, Michaels addressed the topic once again.
โWe werenโt besties, but we were partners on a television show for a very long time,โ he said, while explaining why it “spoke volumes” that Michaels didn’t reach out.
โI would not expect Jillian Michaels to do anything other than what she wants to do,โ he added.
What Has Michaels Said About Her Friendship with Harper?
Following Harper’s heart attack, Michaels offered the following comment in 2017 while appearing on E!’s Daily Pop.
โKnowing a little bit about Bob, I know that he does have a family history of it. I was there when he lost his mother to a heart attackโ with him the night that she died. So there is a family history,โ she said.
As Michaels went on to explain, she suspected that Harper’s adherence to the Paleo diet, which he no longer follows, and love of CrossFit played into his health.
โItโs not a great combination with poor genetics,โ she said. โNot that he has poor genetics, but if you have heart disease in your familyโฆ .โ
During the interview, Michaels also said she understood why Harper is a fan of CrossFit.
โHe loves it, and he loves the community, and he loves the challenge … from what I remember of Bob, heโs looking at it, and heโs like, โWell I can!โ Heโs not thinking about it that way. He, personally, is like, โI love this challenge.โโ
So far, Michaels has not replied to Harper’s claims that she did not reach out to him after his heart attack. TODAY.com has reached out to Michaels for comment.
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