Fundamental Motor Skill Acquisition ?'s

.....some motor skill training questions1) When choosing t-spine mobility drills do you find ones that work better than others? Or do you just go with whatever changes the pattern? I find myself using quad/lumbar locked variations, rib rolls and Brettzel positions the most. Does the Brettzel even qualify as a t-spine mob?Of the choices you mention, I find that they all can work, but I will get the most use out of Rib Roll and Quadruped T-Spine Lumbar-Locked.  For those that are more than fairly limited, these options still allow for them to get into a decent position and progress on their own.  With Quadruped T-Spine, the phasic arm position is a consideration.  Most people who have a shoulder motion limitation will also have a t-spine limitation, and the IR position stiffens both up.  If we leave the IR out and use the cross-arm position instead, we can address the t-spine alone and then back-fill the shoulder motion if it is still needed.  The ER position, I have found, is useful for only a warmup or cooldown.  Anyone that needs the drill for a motor skill regression can't do the movement adequately.  And for those that can, they don't need the motor skill.I do count Brettzel as t-spine.  Here is its namesake, Brett Jones, with a brilliant introduction to coaching the Brettzel.  I have found that for those with upper half limitations, the Rib Roll is far more useful, so we won't go to Brettzel until someone can get 1 fist (their fist) off the floor in the Rib Roll.[embed]https://www.youtube.com/watch?v=yMnamNJZMBk[/embed]Some T-Spine options assisted and assisteare....1x1-2: Pressup w/packed neck, Rib Roll, Brettzel2x1-2 - Quadruped T-Spine, High Quadruped Lats, High Quadruped T-Spine Extension3x1-4 - Half Kneeling Hips, Seated/Kneeling T-Spine Ext or Rotation, Half Kneeling OH Rotation, Kneeling Halo4x1-4 - Standing Rotation, Standing HaloAll of these can be executed with combinations of barrier engagement, high tension strategies like hold-relax, and breathing.2) If someone is dysfunctional with lumbar locked/ext rotation could [one] use this position as a corrective...or ....check..int. rotation first to see if it's a t-spine issue, in addition to checking to see if lat or pec length is an issue?As I mentioned above, I insist that anyone that can execute Quadruped T-Spine w/ER doesn't need to do it for the purposes of improving mobility. It doesn't change competency (you already have it), and it doesn't add power or endurance. So why would you do it?I've also never seen someone suck at Quadruped T-Spine w/ER and then actually get better at it by doing it.  It fits the 1st criterion for motor skill acquisition of putting the individual up against their barrier or success, but it does not fit the 2nd of having a progressively increasing level of success.If the elbow doesn't stay in line with the shoulder, this drill is not being executed properly.  There is likely a TED somewhere in the system particularly if T-Spine is improved in other arm positions that do not challenge the gleno-humeral joint or scapula. 3) Where in a corrective strategy does Kolar's dying bug or other deadbug progressions fall?  Ive used them as anti-ext. excercises, but wondering if they can be useful in other situations.I've found this movement useful in post-abdominal trauma SMCD's such as post-partum or abdominal or spinal surgery.Depending on the individual's current strategy, I could see it coached for anti-extension or anti-flexion.I think most people do them just to do them, or someone they look up to says to do them, but rather they do nothing to change motor skills beyond the severely restricted.  It's just an EMG or biomechanics-based exercise that does nothing more than burn calories or act as a weak warmup most of the time.As far as changing pain, I think it can be very useful again in lower level stricken patients.  In most situations, there are simply better options.4) I've used single and double leg bridge progressions for many years...... I'm now starting to look at them more as a core exercise than as a true posterior chain strength exercise......does the slide board leg curl really build strength in the glutes/hamstrings or is it really a display of proper core strength allowing the glutes and hamstrings to work correctly....? Deadlift variations seem much more useful and I'd rather do 2 days of KB deadlifts with someone.....than.....a bridge variation.Irregardless of likes or dislikes of any option, again, if a choice doesn't change competency or add capacity, it is nothing more than a warmup or cooldown.  That doesn't cheapen an option.  It just best positions it.I think bridges are a very useful warmup, but not for any suggestion of "activation."  In some individuals, I would not argue utility in changing muscle stiffness between hips and spine in terms of a TSPU or ASLR pattern.  Bridges could also be a regression for squatting or deadlifting in a highly deconditioned or elderly individual.SBLC I think can be useful for the same reason as well as supporting double leg hinging patterns in a lateralization.If someone could Double KB DL, I'd choose that over everything else previously discussed for a warm-up, cooldown, or a main lift.5) As far as side bridges go, I use them as a lateral stability exercise (as well as shoulder stability), but where would they fall in the corrective strategy for you?Side Bridge is a TSPU static stability regression in my mind, but in older FMS Level 2, it was an RS regression. In the end, anything can correct anything regardless of how it is positioned in a commercial product.  I think it also makes a lot of sense as a static stability option for a shoulder or other upper quarter SMCD.The plank variations in general, in my mind, are strategies to teach the motor skill of stiffness and tension in the vertical position.  If we can feed tension forward in lower positions, I think it can potentiate feedback tensions in the vertical especially when speed or fatigue are part of the drills.