Kinematic Sequence Question
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Ed C
4 years, 9 months ago
This may be a silly question...
To my untrained eye, in the kinematic sequence chart of an elite golfer (link to graph below), the pelvis, thorax, and arm are all slowing down in rotational speed before/at impact - it makes me wonder if the rotational speed of the club could be increased further if they were all peaking at the same time right before/at impact? Or in reality, do the muscles in the human body somehow fire better (faster) as a result of sequencing/peaking in that particular order?
https://www.mytpi.com/articles/biomechanics/the_linear_kinematic_sequence
3 Replies
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Tyler Ferrell
Coach
4 years, 9 months ago
It looks like you didn't quite finish your last thought.
But I'll give an opinion about the first part. The kinematic sequence is well known for rotational sports. The exact timing depends on a few factors (like how long or heavy the implement is). In golf, the club is long enough and heavy enough that you need more time to transfer the speed to the clubhead than say throwing a baseball. So the pattern of the sequence will be similar, but the details will be a little different. You mentioned are the muscles more effective when fired in a sequence. For speed, yes.
That said, there is some debate on the exact graph shape and pattern. Dr. Kwon shows in his graphs that the shoulders to ribcage peaking order could be reversed depending on how the data is collected. So the exact timings of the peaks may be more stacked than first reported.
I think there are a handful of keys to learn from the sequence.
1 - Everyone shows the hips going first.
2 - Everyone shows the slopes to be somewhat similar (good use of connectors/stabilizer muscles).
3 - Everyone shows the peaking happening around delivery position and then a decelerating of the body as the wrists and club accelerate rotationally
4 - The majority of elite golfers show the club head reaching peak speed at impact (amateurs often peak early)
5 - The majority of elite golfers show the thorax moving faster than the lead arm at impact (amateurs are usually reversed)
Hopefully that helps,
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Ed C
4 years, 9 months ago
Thanks for the feedback.
Do the connector/stabilizer muscles, by stretching and contracting, help generate more speed - for the next body part - as the swing moves through the kinematic sequence?
Not sure if I said or asked that right, but I'm merely trying to develop a very very basic understanding for why the human body produces an ideal swing with amplitudes peaking in a sequence, as opposed to peaking all at once.
The interest stems from ... curiosity.
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Tyler Ferrell
Coach
4 years, 8 months ago
Having something for the muscle to resist allows it to create more force. Imagine trying to life an empty milk jug, you couldn't activate your muscles nearly as fully as if you were trying to lift a heavy weight. Same rule applies. The kinematic sequence creates more time (to create force) and creates more resistance for the next segment to activate against.
It's why most people can jump higher with a running start. The muscles that slow down the run, also contribute to the jump. Because the muscles slowed down the run, when they go to jump, they have been activated at a higher intensity and so you jump higher.