Make Muscle Mass for Shoulders and Traps

In reality, shoulders are such a small muscle group that it's easy to over train them. Shoulders muscle respond well to heavy weights - as well as light weights and high reps - but not too heavy and not too often. The shoulder joint is vulnerable and doing behind the neck barbell presses with too much weight and a grip too wide can lead to injury. These non-pressing movements are guaranteed to make your delts and traps muscle pump and grow.

                                REAR-DELT LATERAL CABLE RAISE

Probably the best known way to work rear delts is with bent-over dumbbell laterals. Another way to really smoke 'em is with cables. Place a flat bench about 3 feet away from a low pulley. With one hand, grab a stirrup handle and lie down on your side facing the low-cable pulley. Bring the arm up and back in line with the body. Squeeze the rear delt muscle at the top peak-contracted position. Slowly lower the cable back down and repeat. Go for reps 12-20 for each side.

                              BEHIND-BODY CABLE SIDE LATERAL

In Arnold Schwarzenegger's The Encyclopedia of Bodybuilding, Arnold is pictured doing this exercise. Talk about showing his incredibly separated delts muscle. What inspiration! And if you do them correctly, you're bound to be inspired by the results that will soon be apparent.
Place a small bench about 3 feet away from and directly in front of a low pulley. With the cable handle in your left hand, sit on the end of the bench with your right side next to the apparatus. With the cable behind your body, raise your left arm out to your side and up to shoulder level. Hold in the peak contracted position for a count, then slowly lower and repeat. Go for 12-20 reps for each side.

                                    STANDING CALF MACHINE SHRUG

And you thought the standing calf machine was just for calves. It's a great way to work your traps muscle, and you don't even have to hold on to anything.

With feet flat on the floor or on the block, position yourself under the standing calf machine, just like you would if you were going to do standing calf raises. With the pads resting on your shoulders, legs straight and upper torso erect, lower your shoulders, then shrug them up as high as possible. Hold the shoulders up and keep the traps muscle in the fully contracted position for 1-2 seconds, then slowly lower the shoulders and repeat. Do as many reps as possible.