1]"Nothing special about his windup". I recently stated along the lines that...."loading is only as effective as it helps to UNLOAD." Paul, similarly, is hinting at the fact that is NOT primarily about loading. More fundamentally, it is about how one unloads.
2]Yes, of course, this DOES relate to loading. But I think the fundamental point is: One cannot NECESSSARILY conclude as to how one is going to unload....
3]..., based on loading parameters such as , stride length, tempo going into foot plant, exact throwing arm alignment, etc.
4]I do think that SOME loading parameters ARE pretty vital. One is that of creating a sufficient degree of scapula RETRACTION [otherwise known as horizontal adduction of the shoulder].
5]Kelly does create this kind of scapula action. But what really strikes me as significant is the SPEED of the "reversal" from maximal retraction, to "lag" to release.
6]In looking both in real time and slo-mo, it appears to me to be ....VERY QUICK!!
7]This kind of load/unload quickness is [of course] very consistent with research regarding "stretch-shortening" processes wherein a reduction in the "amortization" time yields greater power.
8]Along with the noted speed of the upper body unload, I would further note that one can infer the "fullness", so to speak, of the connection of the finger release to the more proximal shoulder component [the scapula musculature].....
9]...by looking at both the flexion of the trunk and the "finish"[so to speak] of the throwing arm. Note the rapid flexion of the trunk [and note the magnitude].
10]Based on everything I know about momentum processes this is a REACTION to the combined angular rotation of the upper trunk and the scapula protraction of the back scapula.
11]You can further infer this from looking as to the "finish" of both the throwing arm and the body mass, ie., both are displaced towards the first base dugout.
12]Bottom line: Kelly, like ALL other hard throwers, creates VERY good shoulder rotation, and VERY good physical linkage between the distal element [hand/ball] and the more proximal linkage [back side scapula].Better known as CONNECTION.
These 2 clips are very good [but pretty subtle] examples of what I refer to as the relatively subtle difference between "squatting" vs. "sitting". Let me try to explain this subtle difference. And it CAN POTENTIALLY effect the swing [unload].
1] Note the basic initial set-up difference. On the left he is creating greater knee flexion/trunk tilt; on the right he starts with less knee flexion and less trunk tilt.
2] But from there as he starts to move [stride], on the left the first action is more knee flexion[subtle] --what I refer to as "squating"; as opposed to "pushing the hips back" via HIP FLEXION seen in the right clip.
Probably close to 20 yrs. ago is when I first ran across the concept of the "serape effect." This preceded finding Tom Myers's "Anatomy Trains", and along the same time I found Mel Siff's "PNF" exercise programs, and preceded finding "biotensegrity models."
ALL of which I find related in the sense that they all helped me to better understand how to think about, as I sometimes simply phrase it, "how the body works" in the specific context of throwing/swinging.
Here's a link I cited and talked about quite a few yrs. back about the serape effect:
I've talked about this before. I think the best physiological/biomechanical explanation is that the back leg action [post contact] is a REACTION to the upper trunk's [arms/bat included] angular momentum.
Said another way: It is a function of the distal component [the back leg] attempt to create greater gyroscopic stability, ie., as the as the trunk leans forward and as the arms/bat go "out and around" to get to the low/outside contact point, the back leg tries...
....to "offset" that action by essentially reacting in the opposite direction.
As always, Paul's comments are very thoughtful and relevant. I want to try to add some context here as regards how to effectively deal with this "disconnection" problem as a teacher.
By "disconnection" I mean that the flawed movement that one is trying to change is a function of a movement pattern that has been done MANY times, and as such it has become AUTOMATED ,ie., not consciously derived/executed.
It may have initially been a function of some type of explicit instruction, eg., "stay back," "swing down", "make your hands quicker",etc., et al, but regardless as to the origin, eventually [via trial/error/repetition], the movement becomes tacitly expressed.
To add some context to my following comments, I would suggest looking at some of my ending comments about motor learning theories in my most recent threadreader post.
Let me say at the outset that I am no novice to books on motor learning/motor control THEORIES [my emphasis because I want to denote that MUCH of the research is simply that ----theory---as opposed to well established physics views on how things work, so to speak].
[Yes I do realize that various aspects of quantum mechanics has muddied the waters, so to speak, but for now I'll simply assert that Newtonian physics is more grounded relative to motor learning theories].
Before I start, I want to thank "Hitters Edge" for putting this up. The real value of a clip like this is that it gives you a rapid compilation of a single hitter swinging at a variety of pitch speeds and locations.
Thus allowing a quick comparison and analysis of the kinds of similarities and differences --within 1 great hitter---that can be gleaned.
Let me add a little context to this clip by saying that these are most certainly not the first clips of Kenny that I have tried to analyze. My guess would be that I have spent at least 100 hrs. [starting at Setpro around 2001] looking at Kenny's swing via slo-mo and real time.