Hey i was at the gym today and i was wondering when u do shrugs with the bar behind you , if it work a different part of yuor traps , my traps are a good size as of now , but i want the peak at the top and i want them to show more and the back, should i do in front and in back to get that ? oh and also how is doin shrugs on the smith machine , or is it better free weighted?