Sounds like to me the cat don't like you touching his legs. Try to see if it is hurting him when you do touch them. I hear they are good at hiding pain but if you are concerned contact your vet to make sure there isn't something going on.
Is your cat walking normally? Limping? Not standing long or favoring that leg in any way at all? If so, I'd call your vet. She just may not like to be touched on her legs.