Giant Set 4: Seated Shrugs/Supinating Shrug. Work the traps with a seated shrug which will help focus on the movement of the muscles by taking momentum out of the equation. Move straight into a supinating shrug which will bring in the external rotators along with the mid and upper traps. Remember to have the dumbbells pronated at the bottom and supinate the dumbbell as you squeeze the weight up. Depending on your energy levels, aim for 3-4 sets of 15 reps per exercise. Nick Jones - World Champion Bodybuilder & Justin Wessels - 3x Mr Australia.