heya all,
I’m 20 yrs old, I got 166 pounds. Now, I’ve been training boxing for about 6 months now. Not very actively, cuz in my town we aint got no boxing gym. So I bought a hard bag for home workout. I’ve been concentrating on my boxing technique lately, although I’ve started out more because of fitness reason.
So..my question would be…which exercises would I have to do to have strong back like the true boxers have. I’m not very heavy so I don’t need no huge muscles, but I would like to develop all these tiny muscles on my back, including the bigger ones of course 
Would the trick be just to do alot of heavy bag punching or does it mostly depend on the weights workout programme?
Thank you