It is effortless to keep an eye on areas like thighs and hips when you work out because they are clearly visible from the front and in any mirror. However, unless you position yourself between a few mirrors, even areas that are visible to others – like your upper back and back shoulders – will be difficult for you to see. Sometimes this means “out of sight, out of mind” when it comes to planning your exercise routine. If it is you, your upper back and shoulders can be a little neglected. They may be a little weaker and less shaped than you’d like. If you want to look your best in your sleeveless and / or strapless vacation attire, spend some time exercising those “out of sight” muscles.
The shoulder is a complex structure and that makes it harder to deal with. This is because the shoulder deltoid is not content with moving a bone in a single direction. Instead, fibers from different regions of the muscle are selected to move the humeral bone of the upper arm forward (flexion of the shoulder), backward (extension of the shoulder), sideways (abduction) and back to the body from a starting position with the arm raised. It’s amazing that a triangular shaped muscle can perform all of these functions (and combinations of functions). However, the structure designed for maximum mobility also offers us very poor stability. It’s also a pretty poor mechanical lever, so enormous amounts of force have to be created in the muscle fibers before even the smallest loads can be lifted.
Structure and function
The deltoid is usually described as having three “heads”. While they aren’t actually separate heads, the deltoid comes from three regions on the bony parts of the shoulder. The front part of the deltoid is mainly involved in shoulder flexion (e.g., lifting the arm forward), the medial deltoid is responsible for lifting the arm laterally to the side of the body (abduction of the arm at the shoulder joint), and the posterior deltoid is largely involved in shoulder lengthening (pulling the arm backwards as if setting up a back blow in the pool). Exercises such as overhead presses affect all three areas of the deltoid muscle, but this tends to activate the anterior fibers and only minimally affect the posterior fibers. For example, if only doing overhead presses for the shoulders, the posterior fibers wouldn’t get much direct work at all, and this would eventually result in a poor balance of muscle strength around the very sensitive shoulder joint. Strength and development in one region (e.g., anterior shoulder) but not another (e.g., posterior deltoid) can increase your risk of a shoulder injury, even when performing simple things like a tennis hit or picking up a bag of groceries .
The posterior lateral elevation of the machine preferentially activates the posterior (posterior) portion of the deltoid muscle, and therefore the anterior and medial fibers of this muscle are not discussed further. The posterior fibers of the deltoid are attached along the spine of the scapula (scapula), a bony crest located on its upper and posterior sides. They anchor to the lateral side of the humerus about a third of the way from shoulder to elbow. These fibers create a great deal of stretching (which brings the humeral bone backwards) and this is the main function in lateral elevations of the posterior machine. The posterior fibers also contribute to the lateral rotation of the humerus at the shoulder joint. The lateral rotation rotates the medial side of the arm away from and away from the body (e.g., rotating the arm counterclockwise).
The shoulder joint is between a very flat plate on the shoulder blade called the glenoid cavity and a fairly large ball on the head of the humeral bone of the upper arm. The ball joint arrangement makes this joint the most flexible in the human body, but it is also the most prone to injury. It is therefore common to find that a high percentage of household or recreational injuries are shoulder-related. Many injuries can be avoided if all three regions of the deltoid muscle are stressed and the correct exercise technique is used.
The rhomboids – major and minor – deep back muscles, which lie medial to the shoulder blade, are also activated by machine-assisted posterior lateral elevations. These muscles strengthen your upper back and improve your posture. The rhomboid muscle fibers begin along the midline of the back at the thoracic vertebrae and attach to the medial edge of the shoulder blade (the side closest to the vertebrae). The larger major rhomboid muscle sits just below the smaller rhomboid minor muscle, but both have similar functions. The major and minor rhomboid muscles adduct the shoulder blade (squeeze the shoulder blades together) and rotate the shoulder blade upward (as if you were lifting your arms over your shoulders). The medial part of the great trapezius is located above the rhomboids. The medial sections of the trapezius are attached medially to the vertebrae and laterally to the scapula. The medial fibers of the trapezius support the major and minor rhomboids during adduction of the scapula during retraction in machine posterior lateral elevations.
Lift the rear of the machine sideways
The deltoid works closely with other muscles (e.g., upper back, arms, middle and upper trapezius, and pectoral muscles) in most shoulder movements. This makes it difficult, if not impossible, to isolate regions within the shoulder. As it turns out, the machine’s posterior lateral elevation provides an excellent means of isolating the posterior fibers of the deltoid and the middle and deep fibers of the upper back from the anterior or medial fibers of the deltoid.
1. Position yourself in a seated breast machine (Flye), but instead of looking away from the back pad, your face and body should be in line with it.
2. The machine handles should be level with your shoulders in front of you. You will know that your arms / elbows are in the correct position when they are parallel to the ground when your hands grip the machine’s handles. If not, adjust the seat height on the Flye machine before proceeding.
3. Take a handle in each hand. Your elbows should point towards the back of your body and away from the machine. If you have a pec deck that has padding instead of handles, just put the back of your arms (triceps) in the respective pillow. You’re doing the exercise the same as the version where your elbows and triceps are pressed into a pad instead of pulling back on the handles.
4. Slightly bend your elbows and hold them in this position. Pull your hands back as far as you can. Keeping your arm abducted (to the side), don’t drop your elbow and point to the floor. The trajectory of your arms and elbows should be directly posterior, but movement should be at your shoulders, not your elbows. Focus on moving your arms and back delta fibers as you use them to pull your hands back and squeeze your shoulder blades (shoulder blades) together.
5. Hold the position until two before slowly lowering the resistance back to the starting position. This increases the activation of both the back of the deltoid and the deep fibers of the middle back muscles. Don’t let the weight rest on the stack before starting again. Don’t rest until you’ve done at least 12 repetitions in your set.
You can increase the difficulty of the exercise by lowering the seat so your arms start over a position that is parallel to the floor. This will raise your elbows so they will point slightly down toward the ceiling as they move backwards. This increases the stretch of the fibers of the posterior deltoid muscle from the start and throughout the exercise, thereby increasing activation in that muscle.
If you find your hand grip giving in front of your shoulders and mid back, you may want to switch to the seated pec deck machine. Pressing your elbows into the pads of the pec deck machine and pushing them backwards will avoid grip strength fatigue while still getting a great workout. On the flip side, with the pec deck you lose a bit of freedom of movement, while raising the machine to the side gives you more movement and a slightly fuller contraction at the rear.
It is not necessary or even desirable to try to use a heavy weight with this exercise. The shoulder joint, perhaps more than any other, should be worked with relatively rigorous movements. So if you work carefully and with gentle, rigorous movements, your shoulders will respond, strengthen and tighten. The added benefit is that the muscles in your middle back (between your shoulder blades) are strengthened and toned through this exercise. You may also want to bring out those firm and taut shoulders a little more. After all, your hard work deserves your attention!
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