My weak little arms!

Burrr3Three

So Ive been trying various new machines at the gym, one in particular that you put your knees on and pull them up...I wish I remembered the name of it! It's supposed to work out your abs. The problem is, it kills my sad little arms anyone else having this problem? I'm wondering if I'm just not doing it right or if my arms are still so weak that they need to be built up more?