NBC has revealed the identities of the 20 contestants who will be competing on the thirteenth season of The Biggest Loser, which will premiere January 3, 2012 at 8PM ET/PT.

As previously announced during The Biggest Loser's twelfth-season finale broadcast, the show's next edition will feature 20 individuals comprised as partners in a season of "no excuses." However, the pairs -- which will include parent and child teams, a grandparent and grandchild team, siblings, and spouses -- will not end up working together.

Each set of partners will be separated and must compete against one another, as one member of each team will train with veteran trainer Bob Harper and the other player will work under the guidance of Dolvett Quince -- who will be returning as a trainer for his second season on the show. New trainer Anna Kournikova will not be returning to the series and will be leaving The Biggest Loser after only a single edition.

During The Biggest Loser's thirteenth-season debut, the contestants will immediately compete in a three-part challenge and two of the 20 players who came to the ranch to lose weight with their loved ones will be forced to pair up as strangers.

The 10 teams competing on The Biggest Loser's thirteenth season for the $250,000 grand prize -- as well as their NBC-supplied bios -- are as follows:

Parent and Adult Child Teams:

- Gail Lee, a 57-year-old realtor, and her daughter Lauren Lee, a 26-year-old exercise physiologist from Poolesville, MD

- Mark Cornelison, a 43-year-old youth pastor, and his son Isaac "Chism" Cornelison, a 19-year-old student from Magnolia, TX

- Kim Stone, a 48-year-old registered nurse, and her daughter Megan Stone, a 21-year-old student and support staffer for an organization that assists disabled adults from Dittmer, MO

Grandparent and Grandchild Team:

- Nancy Rajala, a 63-year-old retiree, and her granddaughter Cassandra Sturos, a 25-year-old in-home senior caregiver from Fowlerville, MI

Siblings Teams:

- Conda Britt, a 24-year-old nutrition health services technician, and her brother Jeremy Britt, a 22-year-old banker from Rockford, MI

- Adrian Dortch, a 34-year-old music producer and community activist, and his sister Daphne Dortch, a 37-year-old paralegal and kids activity team member from Evanston, IL

- Joe Messina, a 38-year-old truck driver from Auburn, NY, and his brother Mike Messina, a 41-year-old cook from Oakland, CA

- Allen "Buddy" Shuh, a 42-year-old pastor from Wayne, MI, and his brother Ben Shuh, a 34-year-old retail store manager from Howell, MI

Spouses Team:

- Christine Pickler, a 42-year-old who is self-employed, and her husband Roy Pickler, a 63-year-old self-employed Santa Claus from Middlebury, IN

Strangers Team:

- Emily Joy, a 29-year-old teacher from Huntersville, NC, and Kim Nielsen, a 38-year-old former professional wrestler from Roswell, GA