hope i'm in the right place to ask...

[retired_Benn]

i'm thinking of buying a punching bag...i dont know if this is a good idea, i am hoping to build up my arms and legs, and eventually purchase a speed bag...is it wise for me to buy a bag? i exercise regularly, and am currently taking karate

 

[Exe]

You wanna build mass? gotta do weights. http://www.exrx.net/

Punchbag will just make your arms firmer and improve thier endurance, wont make em grow.