A 9lb house cat can overpower me, and I'm 6ft, 250lb.
Long story short, the GF's cat gets incredibly sick and has to be fed through a tube. Well one day she gets better and decides that she doesn't want to eat through a tube anymore, and that's when I learned just how strong they are. Literally had to use my all of my strength to keep her from squirming, and she was still managing to break free.