According to TV Line, a source revealed that the stars have been working out for two weeks to prepare for the episode.
The scene allegedly focuses on Lauren (Ashley Fink) getting nervous about performing her first solo.
To relax, she remembers that Puck (Mark Salling) once suggested imagining the audience naked.
The episode is expected to air in the middle of February in the US. The show returns in America on February 6 after the Super Bowl on Fox, while the second season continues in the UK on Mondays at 9pm on E4.