The pain of crushing your own genitals against the floor is a big incentive to do the exercise to your own personal max and raise off the floor as high as possible.  When your torso is up and all of your weight is transferred to your legs, you should be OK.  It's getting to there that's the hard part.

Danny, if you don't have that kind of strength or flexibility yet, or if you can't get into the pose fast enough, or hold the pose long enough, talk to your instructor.  She couldn't possibly know what this particular floor exercise does to her male students - unless someone tells her.  If there are other guys in your class, they are probably going through the same thing, so they should be able to back you up if you talk to the instructor.

One Who Knows

>.> Hey Danny, I do these back lifts every night and I know two things that will ease the pain. First, don't do it directly on a hard floor. If you can find a yoga mat, or even a thick rug do the exercises on that. Second, try tucking "it" between your legs so that your weight isn't falling on it. This can be hard in a dance belt sometimes. And just keep trying to modify it until it hurts the least.      >>Hey ppls! Im just wondering.. When im in class doing limbering when im asked to do these back lifts (lay on the floor, tommy down, and life ya back up) I find this hard as it hurts...'down' there. I know it might be stoopid o ask but i was just wonderin fi you have any ideas of how to help? or if that its a usualy thing??