a friend of mine told me that working out stunts your growth.

PLEAS PLEASE PLEASE PLEASE PLEASE tell me this isnt true.

This is a common myth. Working out by itself does not stunt your growth.

Basically, this myth came about because, when lifting weights, it is possible (however unlikely) that you can injure your growth plates. If you injure your growth plates, they can fuse themselves prematurely and that bone will stop growing. The thing is, you can injure you growth plates pretty much any way you can break/impact a bone (sports, etc.). Just learn how to lift with proper form, don't be an idiot in the gym, and you'll be okay.

I've also heard that the extra muscle mass from lifting creates resistance to your bones growing, and your growth plates basically give up and fuse themselves prematurely. This is absolute nonsense.

thanks man i was worried.

Would working out before you're done growing help to increase your height at all, because of the GH increase? Just wondering, because I am taller than both my mom and dad, and I stopped growing before both of them did (my dad stopped at 16, I stopped at probably 15)