NBC has announced an upcoming sixth season for The Biggest Loser, one that will follow the same "couples" format as the show's currently-airing fifth installment.

"The current Couples season of The Biggest Loser has been one of the best and most compelling so far in this important franchise," said NBC executive Craig Plestis.  "We look forward to continuing to inspire and entertain viewers with more remarkable and life-changing weight loss stories."

The show's sixth-season, 13-city casting tour will begin on February 16 with stops in Boston, Dallas, Chicago, Atlanta, New York City, Nashville, Oklahoma City, Miami, Columbus, Suffolk, Las Vegas, Mesa and Los Angeles - all of which producers have described as America's "fattest cities."

"It has been so satisfying to watch this franchise continue to grow," said executive producer JD Roth, "and Season 6 will be another opportunity to tell powerful, transformative stories of Americans getting their lives back in a healthy, positive way."

Alison Sweeney (from Days of Our Lives) will reprise her role as The Biggest Loser's host for the show's sixth installment, which will also include trainers Jillian Michaels and Bob Harper.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.