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Huge Rear Shoulders Through Bent-Over Dumbbell Lateral Raises |
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Written by Stephen E. Alway, PhD, FACSM
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Tuesday, 24 April 2007 |
Huge deltoids can make a good upper body great. They project laterally and posteriorly so the trapezius muscles appear thicker and the back muscles emerge wider and denser. Given their importance, why doesn't everyone have great shoulders? Well, it's not a simple task, because the shoulder is by far the most complex joint in the body. It's a very mobile joint, but this makes the ligaments, muscles and tendons vulnerable to injury, especially if there are any unbalances in muscle structure around this joint. The posterior region of the deltoid is one of the most neglected areas of the shoulder. Strengthening the posterior deltoid will help stabilize the shoulder if it's hit from the back or if you fall on your shoulder in a contact sport. A stronger and thicker rear deltoid will also improve your ability to pull the arm posteriorly (extension of the arm, which brings it backward), thereby enhancing your back exercises by allowing you to use more resistance in rowing and pulldowns. One of the best approaches to building mass and strength in this area is through bent-over dumbbell lateral raises.
Muscles Activated: Shoulders and Deep Back
The shoulder is capable of flexion and extension and the deltoid has a major role in both of these functions. The anterior (front) fibers of the deltoid attach along the lateral part of the clavicle (collarbone) above the shoulder joint. The anterior fibers produce strong flexion of the humerus at the shoulder (bringing the humerus bone of the upper arm forward) and medial rotation of the humerus at the shoulder. The humerus bone rotates at the shoulder so that the anterior aspects of the arm and palm of the hand are turned toward the mid-line of the body. The posterior fibers of the deltoid attach along the upper and posterior side of the scapula (shoulder blade). These fibers produce strong extension (bringing the humerus bone posteriorly) and this is the primary function in bent-over dumbbell laterals. The posterior fibers also contribute to lateral rotation of the humerus at the shoulder joint. The medial fibers of the deltoid sit on the lateral side of the shoulder, attaching between the anterior and posterior fibers of the deltoid. The medial fibers abduct the humerus (raising the humerus away from the side of the body).
Our Maker designed shoulders for rotation and maximum mobility, but the design sacrifices joint stability. The shoulder is also a rather poor mechanical lever so tremendous amounts of force must be generated within the deltoid fibers even before the smallest of weights can be lifted. Thus, the deltoid has the potential to generate high and potentially injurious forces through this unstable joint. Bent-over dumbbell laterals will help to strengthen and thicken the posterior fibers of the deltoid and this helps to prevent forward (anterior) displacement of the shoulder.
The rhomboids major and minor muscles are deep muscles of the back that lie medial to the scapula and are also activated by bent-over dumbbell flyes. These muscles can add both thickness and detail to the back when the body fat is reduced to competition levels. The rhomboid muscle fibers begin along the midline of the back at the thoracic vertebrae and attach on the medial border of the scapula (the side closest to the vertebrae). The larger rhomboid major muscle sits just below the smaller rhomboid minor muscle, but both are mechanically similar. The rhomboid major and minor muscles adduct the scapula (squeeze the shoulder blades together) and rotate the scapula upward (as when you raise your arms over your shoulders). The medial fibers of the trapezius muscle lie over the rhomboids and assist them in scapular adduction during the upward lift in bent-over lateral raises.
Bent-over Lateral Raise
The posterior fibers of the deltoid, rhomboids and medial trapezius muscles are the prime targets in this exercise.
1. From a seated or standing position, bend over so your back is parallel to the floor. The seated position (e.g., at the end of a bench) is best for anyone with lower back weakness or injury. Your arms should hang toward the floor with your thumbs adjacent to each other in the bent-over position. If standing, your knees should remain slightly bent and remain in this position for better balance and to reduce the likelihood of lower back strain.
2. With your elbows slightly bent, raise the dumbbells out to the side of your body and as high as possible. The trajectory of the dumbbells should fall slightly behind your shoulder joint, but the dumbbells should be raised to the same height as the level of your shoulder joint (or higher, if possible). Your elbows should be pointing toward the ceiling throughout the rise and descent of the weight.
3. As the dumbbells approach the top position, rotate your arm at the shoulder joint so the lateral side of your hand (the side with the thumb) is pointing toward the ceiling. This rotational movement is the opposite of what you might normally do for this exercise. It might seem awkward at first and it will likely take some effort to perform this correctly. However, after you have learned to put this lateral rotation at the top of the bent-over dumbbell lateral raise, you will experience an extra burn in the posterior deltoid that you have not felt before.
4. Hold the top position for a count of two. This will really force the deep middle back muscles and the posterior deltoid fibers to smolder throughout the contraction, but it will be worth it.
5. Slowly reverse the movement to the starting position. This will result in medially rotating the arm at the shoulder joint and then controlling the descent to a position with your arms perpendicular to the floor.
6. Do not pause at the bottom or between repetitions, but immediately continue upward. Your posterior shoulder should be under constant tension from the beginning to the end of the exercise.
Important Tips
The bent-over dumbbell lateral raise incorporates both the shoulder extension and lateral rotation functions of the posterior fibers of the deltoid and the scapular adduction functions of the rhomboids and trapezius muscles. Lateral rotation does not usually occur in most training schedules, and as result, you can expect some post-training soreness. It's very important to rotate your arms (humerus bone) at the shoulder joint rather than at your hand and wrist in the top portion of this movement. Simply supinating and pronating your hand involves movements in your forearm, but that will do nothing to help your posterior deltoid. It is equally important to keep in the bent-over position throughout the exercise, otherwise the work of the posterior deltoid fibers will be minimized and the trapezius, medial deltoid fibers and other smaller scapular muscles will assume the majority of the benefit.
You might be tempted to "cheat" by using momentum from the torso to help the weight move upward once your muscles begin to fatigue. However, this creates an unnecessary torque through the lower lumbar vertebrae and risks injury to the intervertebral discs. In addition, it removes the tension from the middle muscles of the back and most of the tension from the posterior deltoid, as well. Instead, minimize all spine movement after obtaining the correct initial starting position. Thereafter, move only your arms at the shoulder joint. If you become too fatigued, immediately put the weight down and pick up a lighter dumbbell to resume the set, or have a training partner help by pushing lightly on your arms so you can continue the set for a few more repetitions.
Explosive twisting or ballistic rotational movements at the shoulder should always be avoided when doing this exercise. Because the shoulder is literally being held together by its muscle attachments, it's not wise to explode into this lift, especially during the lateral rotation part at the top of the movement.
Try to go for the best exercise form to create the optimal muscle "burn" rather than the maximal weight you can hoist in a sloppy fashion. Extremely heavy weights will impress your friends, at least for the moment, but if you are swinging the weight up and dropping it down uncontrollably, your muscles will get very little benefit- and they will not grow. Do not fall prey to the short-term mind games for heavy weights at all cost in the gym. On the other hand, do not use pencil weights, either. The rear deltoid is like any other muscle. It will enlarge and grow dense if you work it using good form with gut-busting effort, but injury or sloppy exercise will not accomplish those goals. It takes a little more thought and work to develop a set of massive and symmetrical shoulders as compared to muscles that have only one function, but the rewards will be worth the effort.
References
Cools AM, Witvrouw EE, De Clercq GA, Danneels LA, Willems TM, Cambier DC 2002. Scapular muscle recruitment pattern: electromyographic response of the trapezius muscle to sudden shoulder movement before and after a fatiguing exercise. J Orthop Sports Phys Ther; 32:221-229.
Gagey, O., Hue, E., 2000. Mechanics of the deltoid muscle. A new approach. Clin Ortho., 250-257.
Halder, A.M., Zhao, K.D., Odriscoll, S.W., Morrey, B.F., An, K.N., 2001. Dynamic contributions to superior shoulder stability. J Orthop Res, 19, 206-212.
Lorne, E., Gagey, O., Quillard, J., Hue, E., Gagey, N., 2001. The fibrous frame of the deltoid muscle. Its functional and surgical relevance. Clin Orthop, 222-225.
Roman-Liu, D., Tokarski, T., Kaminska, J., 2001. Assessment of the musculoskeletal load of the trapezius and deltoid muscles during hand activity. Int J Occup Saf Ergon, 7, 179-193.
Uhl TL, Carver TJ, Mattacola CG, Mair SD, Nitz AJ. 2003 Shoulder musculature activation during upper extremity weight-bearing exercise. J Orthop Sports Phys Ther; 33:109-117.
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