When skinning a limb such as an arm or leg, you can frequently get a bendy or rubber effect. Unless you’re creating a cartoon character, this look is usually undesirable. Magazine 3DWorld brings a quick tutorial how to create a better crease on a limb joint in 3ds Max to avoid this rubber effect.
So if you want to avoid the rubbery look of cartoon characters for a more human appearance then follow instructions in link bellow.
Source: 3D World magazine