Interval training workout programs face competition in the search for America’s next fitness phenomenon.

Terrell Owens joins Jillian Michaels and our judges as they try three fan-based workout programs.

Guest judge Tito Ortiz joins Jillian Michaels in the search for America’s next fitness phenomenon.

Jillian Michaels tests out three of most unusual workouts yet, seeking out a program with mass appeal.

Guest judge Lolo Jones joins Jillian Michaels to find America’s next fitness phenomenon.

Jillian Michaels assesses three innovative group exercise programs.

Jillian Michaels and the judges test three new resistance training programs.

Jillian Michaels and the judges test the stability and viability of three platform fitness devices.

Jillian Michaels, the judges and a panel determine who will be crowned America’s next fitness phenomenon.