Xiaopeng Backward

Morning!  

Was just curious if someone could explain to me the bio mechanism as to why when I'm performing this mobility work, where the "crunching" sound/feeling is coming from. It feels more musculature  than osseous.  & it's much worse in the beginning sets rather than when I'm wrapping them up.  

I'm not complaining, either. Just very curious as to what's compromised in performing this (& grateful that this work will alleviate it!)?

I feel it more at the beginning of the rep with the transition from shoulder extension to flexion...just before my left arm is straight up in the air, if this helps.

Appreciate your insight!

The crunching could be fascia adhesion or bubbles of air. If pain occurs probably the range of motion is forced and you need to twist more your spine in the transition from extension to flexion.

talking about the biomechanics means to talk about the upper arm and its muscles work, the complex of scapulae and its muscles, the complex of AC joint and it muscles and the spine muscles. I think it is a bit complex to be discussed here.

If it doesn't hurt, it usually doesn't matter.

During a Xiaopeng, the humeral head will both rotate and glide over the surface of the glenoid fossa. If the surfaces are not congruent, then you might feeling a crunch, pop or "give", and these may also have sound associated with them. The sound (crepitus) is apparently nitrogen or carbon dioxide being squeezed out of the synovial fluid that lubricates the joint surfaces. At least, this is what I read about it during studies a few years ago.

Just as you're about to reach the top of the Xiaopeng, your upper arm + humeral head will start to rotate, so this is where the joint surfaces will likely be less congruent - it's not a "normal" position for a lot of people, so the surfaces won't have adapted to it. Joint cartilage does adapt, it just takes time.

Some - I have no idea how much, it probably differs from person to person - of the joint glide/rotation is is controlled by the rotator cuff muscles (supra/infraspinatus, subscapularis and teres minor). Depending on the amount of contraction and relative amounts of contraction of each of these muscles, plus the force exerted by the larger muscles around the shoulder (traps, pecs, lats, deltoids), the rotator cuff muscles may keep the humeral head moving on the glenoid in a "normal" manner. "Normal" means the right amount of glide/slide/rotation for you to be able to complete the movement.

It's possible to change the degree of activation of the rotator cuff muscles a little, sometimes this might reduce the cracking and popping, sometimes not.

Try:

• gripping the weight a little more tightly, or less tightly, and see if this makes a difference. An article I read somewhere stated that a tighter grip activates the cuff more as there is feedback to the shoulder that something heavy is being held
• do some hinge rows (1 set of 10) before the Xiaopengs and see if that makes a difference (more lat + external rotator activation)
• perform the Xiaopeng as half a dislocate: slow it down a bit and actively push the weight AWAY from the shoulder at all times: the movement of the weight is a large circle; make the circle as WIDE as you can.

 

Dope!  Thank you so much for elaborating on this, Nick! I was initially thinking my supraspinatus tendon may be compromised with this motion, but I figured someone here may have a better idea.  I appreciate your insight! Rock on, bro.