The Biggest Loser viewers won't have to wait long for the show's next season.

NBC has announced The Biggest Loser's fifth edition will premiere with a two-hour episode on Tuesday, January 1 at 8PM ET/PT, exactly two weeks after the finale broadcast of its currently-airing fourth installment.

NBC's decision to debut The Biggest Loser 5 as primetime midseason programming represents the first time the network has aired two regular The Biggest Loser editions in the same television season.  All four of the The Biggest Loser's four previous editions had aired as part of NBC's fall schedule.  (The only exception was The Biggest Loser Special Edition, a spin-off that aired a six-episode run in January and February 2006.)

Also for the first time in the show's history, The Biggest Loser's fifth-season contestants will compete while paired in teams with somebody they have a pre-existing relationship with (such as a family member, friend or coworker). 

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.

During The Biggest Loser 4's premiere broadcast in September, a "surprising new twist" resulted in Lyons taking control of the traditional Red Team, Harper helming the traditional Blue Team, and Michaels training a new "secret" Black Team of contestants that had failed to be chosen for the other two trainers' squads.

"When those doors opened, the first thing I see is Jillian," said Lyons during The Biggest Loser 4 broadcast when Michaels and her secret Black Team were revealed.  "The competitor side of me was just like, 'No way! I can't believe she's back!'"

When reached by Reality TV World, NBC attributed Lyons' The Biggest Loser 5 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.

The Biggest Loser 5 -- which is still in production at an undisclosed location -- is expected to run 14 episodes, most of which will be two-hour broadcasts, according to an NBC spokesperson.

New fourth-season host Alison Sweeney will return to helm The Biggest Loser's fifth edition.

The Biggest Loser is a production of Reveille LLC, 25/7 Productions and 3Ball Productions.  Ben Silverman -- NBC's programming chief and a reality television producer who launched Reveille in 2002 before producing The Biggest Loser for NBC in 2003 -- serves as executive producer for the show along with  Dave Broome, JD Roth, Todd A. Nelson, and Mark Koops.