Hand & wrist conditioning

I need some serious hand and wrist strength and conditioning advice. I would want to be able to defend myself if the need would arise, but I feel so weak in those areas I feel like delivering a solid punch would break my knuckles and jar my wrist. It's even bad when I'm hitting the punching bag. I cannot hit the bag as hard as I can because my wrists can't seem to absorb the blow.

I've heard of people doing knuckle push ups to strengthen their knuckles, punching thick newspapers tapped to...

Hand & wrist conditioning