The shoulder is made up of the anterior, medial, and posterior deltoid muscles, all of which you can tone with raises and presses. The presses are compound exercises that incorporate more than one shoulder muscle, while raises are used to isolate one muscle in particular. As you lift, your sets and reps will vary depending on what phase of training you are in. One of the worst things you can do is maintain the same sets and reps constantly.
Whether using a barbell in front of or behind your head, or using dumbbells, overhead presses are the major compound movement for shoulder exercises, and are recommended by Stack.com. When you begin your training program, you want to do more reps with light weights to build a base of strength. For the first two weeks, you should do four or five sets of 12 reps. After that, move your reps to six to 10, while keeping the sets the same. Two weeks later, you will begin the last phase of your cycle. The weight will be heavy, so three to five sets of no more than five reps are most effective. Once you have done this for two weeks, start all over again -- but the weight you lift should increase dramatically.
To isolate the medial deltoid, lateral raises are the primary exercise. Stack.com recommends using dumbbells of light-to-moderate weight. As you perform the move, keep your wrists locked and raise the weights up from your side to shoulder height. For the first two weeks the weight will be lightest, so five sets of 15 reps is ideal to fatigue the muscle. After two weeks, you should drop the reps to 10, and two weeks after that, the reps should be no more than five. This six-week training cycle is ideal for preventing muscle adaptation, which lowers the effectiveness of the exercise.
The anterior deltoids are used in the bench press and several other lifts, so it is less essential to isolate these muscles than the other two. However, Military.com names front raises as one of the top shoulder exercises, and these are an effective addition to your routine. With dumbbells or weight plates held at thigh level in front of the legs, raise your arms, with palms down, to shoulder height. Do not bring the weight together, but keep your arms shoulder width apart to best isolate the muscle. In the first phase of the cycle, three sets of 10 is sufficient, while the sets should move to four and the reps down to eight for the second phase. In the final phase, using heavy weight you should raise the sets to five and drop the reps to five.
The posterior deltoid is often overlooked in training. Bent raises are best performed while seated to protect the lower back from injury. Bend forward at the waist, but keep your head up to further protect the lower back. Begin with the dumbbells together beneath your bent knees. Raise them up and out, bending the elbow approximately 90-degrees throughout the movement. Since posterior deltoids are rarely activated by other movements, you should perform more bent raises than any other isolation movement. In phase one, five sets of 15 is ideal, and in phase two and three, you should maintain the five-set routine. Decrease reps to eight to 10 in phase two, and four to six in phase three.
Shrugs are the odd shoulder exercise. The reps will be much higher than other movements. Shrugs primarily activate the trapezius muscles, but also incorporate the medial deltoids; when done with a barbell, these incorporate the anterior deltoids as well. IDEA Health and Fitness Association recommends these as an effective exercise that you can easily perform at work -- just keep a set of dumbbells in your desk drawer. In phase one, perform three sets of 20 to 25 reps. Be sure that you do not roll your shoulders; simply raise them up and down. In phase two, four to five sets of 15 to 20 is ideal. In the final phase you should do five sets of 10 to 12 reps.