Darren Criss - Criss Took Boxing Lessons For Tough Glee Scenes

The singer/actor performs a rendition of Christina Aguilera's hit Fighter in this week's (begs09Apr12) installment, and he is shown taking out his aggression on a boxing bag.

To prepare for his character Blaine Anderson's scenes, Criss was given tips by boxing experts - but he was also warned not to take up the sport as a hobby for the sake of his music career.

He tells EW.com, "Yeah, I hit pretty hard, but I'm also really terrified because I think my friends who box will be like, 'Ugh, this guy doesn't know what he's doing.' As they should because I don't and I'm not a boxer. A while back when I found out Blaine was gonna be a boxer, I went to this famous Hollywood boxing club and I kinda got put through the ringer, literally.

"It was really funny when I went the first time, I just said, 'Hey, I just kinda need to know what I'm doing so it looks effective on camera.' Then towards the end of it my hands were hurting pretty bad and I was like, 'Is there any way I can take any precautions? I use my hands - I'm a musician.' The guy was like, 'You're a musician? Professionally? What do you play?' I said, 'A little piano. A little guitar.' He just looks at me and goes, 'Yo man, you can't be boxing!'"