For the first time in the show's history, The Biggest Loser contestants will compete while paired in teams with somebody they have a pre-existing relationship with.
While nine of the 10 teams -- including a mother and son; mother and daughter; two husband and wife teams; a divorced couple; best friends; father and daughter; brothers; and former football teammates -- already have a bond, the tenth team will consist of two strangers who didn't meet until they were paired together.
Throughout the season, the teams of two will be training, competing in challenges, and weighing in together rather than as individuals for the chance to claim the $250,000 grand prize.
Bob Harper and Jillian Michaels will both return for the show's fifth edition, however Kim Lyons -- who replaced Michaels as the Red Team's trainer prior to the show's third season -- will not.
When contacted earlier this month, NBC attributed Lyons' The Biggest Loser: Couples absence to her decision to "pursue other opportunities," including the promotion of her upcoming book. "Kim Lyons' Your Body, Your Life" -- a new exercise guide penned by Lyons and published by Sterling Publishing Co., Inc. -- is scheduled for release in January.