About The Biggest Loser Season 12, Episode 12 :

The stakes are higher than ever when all the contestants return to the same spot where they had their first challenge to compete in a marathon. For the first time in the show's history, the contestant who wins the race automatically becomes a finalist, eligible to compete for the $250,000 grand prize. But there's extra incentive because the first five players who finish the race will also get to split $50,000. The only way to guarantee a spot in the finals is to either win the marathon - or be one of the contestants who stay above the red line at the weigh-in. In the end, the three finalists of season 12 will be revealed.