Muscle mass is critical to bodybuilding success, but bodybuilding champions are more than just the accumulation of slabs of beef. If that were not the case, the bodybuilder of average height could never beat a six-foot two-inch athlete. Muscle width, depth and symmetry are additional factors in the formula of bodybuilding success, and the illusive "V" taper with a wide upper back and narrow hip structure is the frame upon which all upper body symmetry is assembled. Even if our Maker did not grant you an optimal bony structure from which to establish your upper body width, you can still build a wide upper back and a "V" taper worthy of many championships. The key is that you must be willing to work hard for it.
Structure and Function
Several upper back muscles contribute to a wide upper back. The most recognizable is the latissimus dorsi muscle and most lifters would readily conclude that building the "lats" is the final word on achieving a wide back. However, this conclusion is a little misleading because, although it is the largest of the back muscles, most of the latissimus dorsi is located in the middle of the back, not the upper back. The fibers of the latissimus dorsi extend from the lower (inferior) thoracic vertebrae and the iliac crest of the hip and the thoracolumbar fascia (a tough connective tissue sheet in the region of the lower back) to converge much like a fan on the upper (superior) portion of the humerus bone of the upper arm, near the shoulder.
This rather extensive attachment probably explains why the ancient anatomists identified it as the latissimus dorsi, which is Latin for "widest of the back." The fibers in this rather complex muscle have several different angles of pull, depending on where the origin of the fibers is located. In general, the primary function of all of the fibers acting together is to extend the humerus (pull upper arm backward), adduct the humerus (bring arm towards center of body), and medially rotate the arm at the shoulder. (For example, if the palm of the right hand is initially facing forward, the latissimus dorsi muscle would rotate the arm counter-clockwise so the palm would turn toward the body).
The lower part of the latissimus dorsi has a more direct line of pull when the shoulder is flexed and the arm is raised to a position that's about 30 degrees above a line that's parallel to the floor. The middle fibers of the muscle have a more direct pull with the hands and arms working at mid-chest level. The upper fibers are best activated with the arms a little above shoulder height. Working with the arms directly over your head tends to activate the middle and lower parts of the muscle more effectively.
Although the latissimus dorsi gives the width to the middle of the back, it's the teres major muscle that provides most of the width of the upper back immediately under the arm, in the region of the axilla (armpit). Development of the teres major is critical for success in poses like the front double biceps and front or rear lat spread. The teres major is also responsible for a wide flare of muscle in the axilla and for creating the tie-in and sweep to the latissimus dorsi muscles.
The teres major muscle begins on the inferior angle of the scapula (shoulder blade), but it attaches high into the same region of the humerus bone of the arm as the latissimus dorsi. Similar to the latissimus dorsi, the teres major abducts and medially rotates the humerus. It also extends the humerus from a flexed position (i.e., with arm forward). Because it begins on the scapula, it's more completely activated with the arms at mid-chest level, or in work directly overhead. It is strongly activated with the arms abducted (wide apart), and therefore, the wide-grip pulldown is perfectly suited to activate the teres major muscle.
The teres minor is one of the rotator cuff muscles of the shoulder. It is located just above the teres major and provides the last bit of width in the axilla, below the shoulder joint. The teres minor begins on the superior (upper) part of the lateral border of the scapula bone. It attaches into the inferior part of the greater tubercle of the humerus (the larger bump near the head of the humerus). It laterally rotates the humerus when it contracts and, similar to other muscles in the rotator cuff, the teres minor helps stabilize the shoulder joint. Finally, it helps to pull the arm backward into extension.
Wide-Grip Lat Bar Pulldown
The lat bar pulldown stresses the extension and abduction functions of the humerus. This extension of the humerus activates the latissimus dorsi and the teres major and teres minor, as well as part of the pectoralis and deltoid muscles.
1. Take a wide pronated grip (palms facing away from your face). Your hands should be about six inches wider than your shoulders. Very wide grips will more completely stretch the teres major and minor, and this may assist in developing some additional upper back width. At the very minimum, we know that muscle stretch under resistance will induce muscle hypertrophy and thickness. Nevertheless, the very wide grip will not be particularly effective for thickening the fibers of the middle or lower latissimus muscles. If you want good upper back width and good tie-ins to the latissimus at the axilla, stick with the wide grip, but if you're after overall latissimus dorsi development, a narrower grip may better suit your needs.
2. Sit in the chair of the lat pulldown unit and position the thigh-stabilizing pad across the anterior section of the middle region of both thighs.The pad should fit snugly on your thighs and prevent your body from lifting from the seat when doing the exercise.
3. Pull the bar down to the top of your chest and make sure your head is moved posteriorly enough to avoid a collision of your chin with the bar. As the bar is approaching your chest, arch your upper back slightly as you attempt to draw your elbows back as far as possible. The extra arch will increases your elbow movement and this will more fully activate the teres muscles by maximizing the greatest range of motion.
4. Hold the lat bar at chest level and squeeze (retract) the scapula together for a count of three seconds. This position emphasizes the arm extension and abduction functions and should result in a good "burn" in the upper back muscles during each squeeze.
5. Slowly return the bar to the starting position, but don't let the weight stack touch the remaining stack. Try to concentrate on feeling the weight stretching the upper back muscles as the bar moves upward.
6. Pause two to three seconds before beginning the next repetition (i.e., at the top of the movement). During this pause, your upper back muscles should be really stretched under the resistance of the weight stack. Under no circumstances should you allow the weight to "jerk" your shoulders upward at the end of each repetition; otherwise you may overstretch the rotator cuff muscle group and de-stabilize your shoulder structures. Furthermore, any jerking into the stretch with a large or ballistic pull will almost certainly injure the attachment sites of these muscles and/or induce tendonitis-like symptoms. After this stretch-pause, continue to the next repetition and complete the set in the same manner.
7. Rather than relaxing completely between sets, use the time to continue stretching the muscles of the upper back. Grip a vertical bar or pole on the lat machine with one hand, bend slightly from the waist and pull to stretch one side at a time. Keep your elbow almost straight, so you feel an intense stretch in the muscles of your upper back as you pull on the pole. Hold each stretch for 10-15 seconds. These stretches will be particularly effective for activating the teres major muscle and they will actually contribute to your muscle width and thickness. Thus, the stretching will greatly improve the overall effectiveness of the lat pulldown.
Training Tips
Stretching between each repetition and between sets is not without risks, if done incorrectly. Again, jerking the weight to stretch your back between repetitions can, and almost certainly will, damage your rotator cuff. Therefore, you need to avoid this. Rather, be in command of the upward movement in the lat pulldown so it's slow and controlled. Hold the stretched position before moving to the next repetition. Always move smoothly into stretches between sets for the same reasons.
If you are persistent and careful, the additional stretches coupled with the wide grip will result in a tight pump across your back in each set. This will quickly translate into a superior upper back thickness and especially width. You'll be amazed at how quickly a few simple changes to an old exercise will greatly change your upper back width and cause you to do some wardrobe shopping. Your friends will ask you how you improved your "lats" so quickly, but you'll know that the lats are only part of the story. Of course, the reason you will now posses a better "V" taper and be closer than ever to your next trophy, is that you have selected the correct exercises, rested and eaten appropriately, and trained safely but harder and smarter than your competition.
References
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Cox, V. M., P. E. Williams, H. Wright, R. S. James, K. L. Gillott, I. S. Young, and D. F. Goldspink. Growth induced by incremental static stretch in adult rabbit latissimus dorsi muscle. Exp.Physiol 85: 193-202, 2000.
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