I dunno I have to disagree with some here... I here people preach all the time go super heavy on traps..and that may work for them..
but IMO traps are not a large muscle group. I see people all the time with 4-5 plates each side shruging (or rather bouncing) away..with virtually no trap development. so really, what muscles are being worked? legs? calves? delts? In reality look at your biceps or even your pecs..they are a larger muscle group then your traps...can you bench 5 plates? Once again, IMO, Traps need to be isolated and hit hard. I have seen my traps grow far larger from doing shrugs with 225 and having no movement in my body except extreme trap isolation, then shrugging with 495 and honestly looking pretty ugly. I honestly have never seen anyone shrug 500 with PERFECT form. If you like going heavy, thats great...if you get good development, keep doing it. But you might try rotating workouts with extreme isolation on the traps and going super heavy. My days of going superheavy are over.. I have a rod and 6 screws in my back...Surprisingly my surgery has forced me to focus more and more on no movement whatsoever and perfect form...and my traps have actually grown.... Legs are another story, as I am only 16 weeks out from surgery and cant put to much pressure on my back that is needed to work legs correctly...
so for thoose of you that shrug and shrug and get no growth..just reducing the weight a bit and focus on form and being super strict till you feel that burn deep in the muscle. You might be surprised. As I always say "check your ego at the door".. I do have to say i always find it amusing when I am doing strict curls with 40lbs and some 150'lbr pulls up next to me and does his full body curls with 45lbs. sorry, just can't preach Form enough.