There are many factors which normally affect pulling biomechanics. Joint angles in the start position, weight distribution through the pull, arm bend during the pull etc. However, there is one thing that has an effect on these factors. I am referring to the packing of the shoulders or the tension created within the scapula. I discuss this very often during my interactions with my lifters as well as during the workshops/seminars that I have done. Creating tension in the upper back or attempting to use the lats is usually interpreted as pinching the shoulder blades back. Yes, that creates alot of tension but in the wrong direction and will subsequently affect your pulling mechanics in the snatch or clean. Here is why: 1. It Shifts Your Pull Forward.
Secondly, if the shoulders are not packed properly in the start position, it causes the combined centre of mass of the weightlifter and barbell to sit forward over the base of support (feet). And when the mass being lifted on the barbell is more than the weightlifter's mass, this means that the combined centre of mass will be further forward upon movement being initiated. So keeping the shoulders properly packed will not only ensure that trunk stability is established but also allows increased balance as the weight is shifted off the ground.
Keeping your scapulas down in the start to help you keep the bar within your base of support (feet) to avoid having the pull go forward. Photo credit to Catalyst Athletics.
When that happens, then as the bar gets pulled into the power position and you already lose the shoulder position, you end up executing the second pull with your shoulders and subsequently the bar sitting in front of where you should be, resulting in your second pull either being initiated too early or your pull being forward.
2. It Reduces The Ability to Create Trunk Stability
When you address the bar and set yourself up for a snatch or a clean, you do your best to maintain tension in the trunk. We are always told to maintain the arch or stay tight as we come off the ground. We assume that by pulling our shoulders back or pinching the shoulder blades, it allows us to create the tension we need for trunk stability or maintain the arch. However, we actually put our lumbar stability in a vulnerable position as the middle back may not have adequate tension once movement is initiated. This will place the lumbar region in a position to work harder to maintain trunk stability and possibly put too much strain on the lumbar region to hold the stability as the load increases.
Losing your shoulder position due to the inability to create sufficient tension is also detrimental in the receiving position. As the movement of the snatch or the clean is so fast, the organisation to create trunk stability at the start is critical to establishing trunk stability in the receiving. In other words, it means there is no time for you to try to tighten up your core any further just when you execute your second pull and before you receive the bar. So if you have lost shoulder tension due to poor packing of the scapulas, chances are that you will have poor trunk stability when receiving the weight and the increased probability of collapsing or not being able to support the weight overhead or on the shoulders.
3. It Can Result in Poor Shoulder Mechanics and Subsequently Poor Performance or Injuries.
Not being able to get the scapulas in the right position will affect the structures around the shoulder joint. Most of the time, shoulder issues arise from the stress placed onto the anterior structures of the shoulder joint/capsule. Like trunk stability, shoulder joint stability cannot be reestablished or created in a a matter of milliseconds. So having the stability from the start is critical to prevent injuries particularly in the receiving position. More importantly, it will promote neuromuscular performance of the supporting structures in the shoulder joint because it allows those muscles supporting the shoulder to work in unison and not get inhibited due to poor position of the shoulder joint or scapulas.
Also, not packing the shoulders appropriately will result in the turnover becoming more of a loop as your shoulder blades are already pinched back. The only direction of pull that your scapulas would be capable for would be towards the back when you perform a shrug for the turnover phase. Depressing the scapulas would then allow correct shoulder blade movement downwards when creating tension and subsequently upwards when finishing the pull.
So we know the issues that poor shoulder alignment or scapula position can cause in regards to your pull and weightlifting performance. Correcting this issues would require a few simple steps. Here is what I normally do with my lifters to allow them to understand shoulder positioning and scapula movement.
1. Power Position to Fully Extended Position.
Packing the shoulders down (scapula depression) in the Power position is easier as you are upright and the movement of your scapulas is more pronounced. From there, the next thing to do is to keep the scapulas depressed and extending up onto the balls of the feet, as though finishing off the second pull. Then bringing the shoulders to the ears to perform a shrug will then allow correct scapula movement (elevation). More importantly, the shrug needs to be performed correctly. Many shrug by pulling back instead of driving up. If that happens, I would suggest even shrugging to somewhere in front of the ears. This will be performed till the lifter is moving correctly and the positions are ideal before more weight or speed is added.
2. Pulls from the Ground then from the Hang.
Next form of correction would be performing the pull movements starting from the ground before proceeding to performing them from the hang. Starting from the ground would allow the lifter to feel the pronounced movement of the scapulas under no tension as the load of the bar has not been added to the demand of the movement. Only until the strength to maintain scapula depression is attained, then the movement can be progressed to the hang variations.
3. Pauses within the Lifts.
By adding a pause in, you not only reinforce position but also build strength in that position (how many times have you held that from most coaches). More importantly, think of pausing the knees and making sure that scapula depression is still active and you do not have to search or find that tension which connects your middle back to your lower back. The two pauses I would recommend would be at the knee as well as at the power position. You also need to sense that you are pretty well-balanced in your paused position but not completely relaxed. For example, in the pause at the knees, the hamstrings need to feel "loaded up" or stretched. If you don't, it probably means you have either sat back further or you have lost tension through the scapulas.
Pause here, ensure "scaps down", "legs loaded" and "balanced weight". Photo credit to Ironmind.
So this is the one thing I personally experience in my lifts where sometimes being lazy, I do not keep scapula depression well enough. It pulls my lifts forward and it also mucks my shoulder up. Might not be the same cause for your shoulder problems but it's definitely worth a try eh?
Stay Tight and Keep Lifting,
The Training Geek