Does building your wrist and forearms help you punch harder and have better form?

I believe the strength of a punch comes from the strength of the shoulder and back.

The form and power comes from your core (hips and torso), not your wrist, forearm or elbow. If you’re practicing chudan punches, include hip flicks when you punch. Stand up straight, but it doesn’t have to be stiff; or if you’re in Zenkutsu stance, make sure your upper body is straight from your hips upward.

As you punch, your wrist should be positioned in such a way that a cup of tea could rest on the back of your hand, and your forearm is bent enough at the elbow so that your punch would land in the solar plexus of an opponent the same height as you. You’re not trying to hyper-extend your shoulder; you could injure yourself.

Stretches

Of course—haven’t you ever seen Popeye?