A former contestant on The Biggest Loser says they 'died that day' after attempting an extreme challenge.

A new docuseries on Netflix, streaming from today (August 15) called Fit for TV: The Reality of The Biggest Loser takes an inside look at the making of the hit reality TV competition that ran for 18 seasons beginning in 2004 and finishing in 2016. Although there was an attempted revival back in 2020.

The three-part series explores the good, the bad, and the complicated during the show's lifespan. It features interviews with former contestants, producers, health professionals and trainers like Bob Harper who were involved in making the show.

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It examines the show’s approach to transformation, the support systems in place, and the unique challenges of filming reality television. Many of those involved reflect back on what it was like to make the show, what it meant for them at the time and how they view it all today.

Tracey Yukich appears in the documentary to talk about her experiences as a contestant. Tracey featured in season eight and says it was life changing.

However, that is not simply because she was just able to lose weight. During one particular extreme challenge set up by the show's producers, she says she had a near death experience.

For the participant's first major mission that year, they were transported away from the ranch that they spent majority of their time in to a beach front location. Crews were filming them from helicopters as well as on the ground.

A mile-long course had been set up along the beach to test each of the new contestants before they had even really started their new exercise regimes. Tracey struggled and collapsed.

Footage is shown of the dramatic moment on the show, where there is serious concern by fellow contestants. The medical team rush onto the scene and they are heard several times exclaiming Tracey is unresponsive.

Describing what happened for the documentary, Tracey says: "I'm running, and my legs feel really heavy. Like lead. What's happening right then is my body's starting to shut down. I might not make it. But I told myself 'I'm gonna do it' because I wanted to change my life."

Tracey is then seen on the show, unable to walk and struggling to speak as she begins to crawl towards the finish line. Other contestants then come over to try and help her. However, as they do and cheer for her, she collapses.

"I don't remember a lot," Tracey says, "I remember hearing the helicopter. I just felt like I was floating. And then my grandpa was there. And then I saw darkness. But then I saw light. So I knew, I knew I died that day."

At the time of filming, it was believed Tracey suffered heat stroke. However, she has since explained it was rhabdomyolysis, a potentially life threatening muscle injury.

"My organs were literally shutting down. I didn't realise that I had rhabdomyolysis. And rhabdomyolysis is your body's way of saying 'I'm going to shut down on you'. It started with my liver, then it was in my kidneys and then it goes to your heart. And that's where I almost died."

Tracey says that she was unable to get out of bed to go to the bathroom herself and could still feel grit and sand in her fingernails. Doctors warned her that they may need to perform drastic surgery to aid her recovery.

She also acknowledges that only the show's medical advisor Dr Robert Huizenga understood how sick she was. Dr Huizenga also tells the documentary that the show did not inform him of the challenge Tracey and the rest of the contestants were undertaking.

Despite what happened, and still feeling physically weak afterwards, Tracey remained on the show. She lasted until week eight, when she was voted off.

Fit for TV: The Reality of the Biggest Loser is streaming on Netflix.