How many weeks are contestants on the biggest loser?

For the latest season (Season 15), the contestants spent 16 weeks on the ranch and then six weeks at home before the finale.

Rachel Frederickson was crowned the winner of "The Biggest Loser" Season 15; she started the season at 260 pounds and lost 155 pounds, that's 59.62% of her body weight.

Despite the criticism that she's lost too much weight, "The Biggest Loser" winner Rachel Frederickson insists that she's "never felt this great." Find out more at ABC News.

Find the latest on The Biggest Loser on Twitter @biggestlosernbc.