A
andrei t
Guest
I dont usually do cardio before my workout (well, maybe a few pushups and crunches)
and i was wondering if running with a backpack with weights in it (6-10 kg) would help me build some muscle mass (especially in the arms or shoulders)...or would it only make me extremely exhausted? have you ever tried this? but running with wrist weights? does this help building some muscles? 
thank you
and sorry for my bad english 


thank you

