Bringing out the shape and striations of the shoulder muscles is a big part of upper-body training, but first you need to make sure you have sufficient delt muscle mass. Here are three tips for adding massive size to the shoulders.

1) Go heavy

Working in the 8- to 12-rep range is generally the best way to add muscle mass to most body parts (the one exception being legs, which respond better to slightly higher reps). But I firmly believe that muscles, especially the deltoids, also need to be subjected to very heavy weight to grow to their potential—a weight at which you can do only 5-6 reps. Go ahead and do lateral raises in the 8-12 range (even 15-20), but I suggest doing overhead presses in the 5- to 6-rep range at least every other workout. It’s not that every set of presses has to be heavy; if you’re doing, say, 4-5 sets of seated barbell presses, you can do your first set or two for eight reps, but then make your last 2-3 sets heavier.

2) Get creative with your presses

Most people vary their shoulder training only when it comes to lateral raises—they’ll do front-, middle-, and rear-delt raises with dumbbells and cables, from different angles—but when it comes to presses, they mainly stick to barbells and dumbbells. There are many other versions of overhead presses that you should work into your delt routine, such as the Smith machine overhead press, Arnold press, both in-front-of-the-head and behind-the-neck overhead presses (using a barbell or a Smith machine) and standing overhead barbell or dumbbell presses (military press).

3) Utilize rest-pauses on presses

As intensity techniques go, I think drop sets and supersets are great when doing front-, middle-, and rear-delt raises. On overhead presses, however, my favorite technique is the rest-pause. The reason behind this is with rest-pauses, you never have to lighten the load—you start with a heavy weight and stick with it for the whole set. To refresh, here’s how to perform rest-pauses: Pick a weight for a Smith machine overhead press with which you can do about six reps. Do a set of 4-5 reps, rest 15-20 seconds, and then do 2-3 more reps with that same weight. Rest another 15-20 seconds, then do another 2-3 reps. At that point, you’ll have done 8-11 reps with a weight with which you could normally do only six. These tips will help spark growth in your shoulders, so give them a try next time delts day rolls around. Follow your pressing moves with high-intensity laterals and you’ll have the best of both worlds: size and definition.

Arnold’s shoulder workout routine

This workout emphasizes going heavy on your first two exercises, and it’s ideal for building massive delts.

Excercise Sets Reps
Smith Machine Overhead Press 4 5-6*
Arnold Press 4 10,8,6,6
Barbell Upright Row 3 8-10
Dumbbell Lateral Raise 3 10-12
– superset with –    
Dumbbell Bent-Over Lateral Raise 3 10-12

* On your last two sets, perform 2-3 rest-pauses.