For every exercise, there's an equal and opposite, behind-the-neck variation. Behind-the-neck lat pull-downs, pull-ups, push presses, strict presses, are just a few examples of exercises I've seen people try to do behind their necks. Perhaps they're trying to hit the same muscle groups in a new way, or target different muscles altogether. Regardless of the reason, I am not generally a fan of the behind-the-neck training club.
Given the overwhelming number of shoulders stuck in internal rotation and spines stuck in kyphosis for the average desk-worker or sedentary individual, many people already come into the gym with a slew of shoulder restrictions and postural limitations. The shoulder is the most mobile joint in the body. Because of the huge range of motion in the joint, many people have poor stability overhead. Men and women alike suffer from scapular flaring (see below) as a result of lifestyle habits and poor posture.
|She may look like she's at peace, but she's forcing her shoulders into an unstable position!|
For starters, let's analyze the neck position of someone doing an exercise behind his neck.
Now, let's move on to what might be happening to the shoulders in a movement like the lat-pull downs in the above photo.
As the result of the neck position, (because the human body works as a chain) his shoulder stability is also compromised. Ideally, his scapula should slide down the ribcage as he pulls the bar towards his traps. However, if the shoulders are internally rotated, the shoulder blade tilts forward and slopes off of the ribcage.
Many Olympic lifting coaches teach jerks or presses behind the neck, because it enables the athlete to keep his torso more upright in the dip. Unfortunately, for most, this might also damage the integrity of the shoulder position in order to maintain a vertical torso.
In an ideal situation, a behind-the neck exercise might be beneficial for an athlete. Unfortunately, the shoulder position is often compromised. If you have had shoulder issues in the past, you more than likely lack mobility or stability in the shoulder joint, and these types of exercises will just exacerbate your issues.
Unless you are certain you can sustain an ideal position in a behind the neck exercise, perhaps your routine is better off without them!