Continuous chain on the upswing to inversion and extension? No! On his 5.95, I count 5 frames where he's stuck in the "flat back" position, and on his 5.60 I count 10. That's a significant improvement after 9 years, but still not Petrov.
So I score Mack a 3 out of 6 on my "Petrov Compliance Scale".
It's interesting that if you watch his vid full speed, he seems to be quite fluid ... in the continuous chain sense. But when you break it down, it's definitely not the Petrov Model.
Kirk
Run. Plant. Jump. Split. Whip. Extend. Fly. Clear. THERE IS NO ROCKBACK OR TUCK!
Hey Kirk..
I have to say he has a “continuous chain”.. big time.. and I will try and explain why… a little later
But first… let me say… his (and B’s) intent has ALWAYS been physics.. which is totally what I have always though we saw when we first saw Bubka jump and what I read in Petrov’s paper and is being called the Petrov/Bubka model, (maybe, and I say maybe because we are making the interpretation, not Petrov or Bubka.. and the same can be said about what we are saying about Tim and B.. this is our “opinion not their’s) I work from what I see from Physics.. application of force.. the picture with the movement…
Tim’s “intent’ has always been to takeoff out.. again always.. in 1995 he had a 53-8 mid and a 12-8, 13 foot take off.. in 2004 his 5.90 jump was 13-8 and 54-8.. a considerable improvement. Yes he is slightly “under’ and as Bubka said he was able to achieve a “free” takeoff some of the time… (Tim may have never achieved a free takeoff... if so he was probally on the wrong pole with the wrong grip and flew over the back of the pit.. the way Tully did the first time he took off "out".).. a faster athlete on the runway has a greater “margin of error” than a slightly slower athlete.. so what is the next best thing if you are only going to have a free takeoff “some of the time”.. it is the
impulse.. which Bubka had in spades.. what Alan calls a “pre-jump”.. Tim worked really hard on having that “impulse’ so he could “negate’ some of the effect of “slightly” under… off course slightly out.. is ALWAYS the first option.. but is hard to control even for the “master’.. the “impulse” can be trained and preformed on every jump if the vaulter drops and “turns the pole over’ correctly over the last 4 steps…
Now to the back flat point… yes I said the “back flat point’ is a “marker”.. but what is happening is the key… off course.. you said 5 frames while in the back flat position.. on most vaulters yes that would constitute a “stoppage” in the chain.. but it Tim it does not.. Tim’s trajectory is different than most others through this position. He is still penetrating and moving forward toward the pit. This is why the bio-mechanist tagged him as “too flat”.. But the fact that it only took him .49 seconds to reach maximum bend and that he had reached the “back flat position” just before maximum bend and traveled forward with the pole (continuous) allowed him to use the swing to “make” the pole reach maximum bend applying force all the way.. the use of his “hands” is really not a use of his hands as such it’s a continuation of the swing all the way Up and around the high bar so to speak.. just as a gymnast will use the “forearm” and grip to propel themselves into the “cast’ concave chest position…..
I think that Tim is more efficient than most in this position because the timing is “natural” to the point that he actually releases the pole just as it reaches it’s maximum length again.. Bubka often released the pole before it had straightened and the vertical lift he may have gained from “swing speed” may have been lost in release height and none vertical pole angle..
Tim tried to take off “out”.. tried to move the pole (grip) up and through at the takeoff and tried to swing like he// off the top…
The fact that it only took Tim 1.43 to 1.46 seconds (depending on how you measure the time of the jump) to complete the jump tells you it was continues.. the pole still moving at maximum bend tells you it was continuous and the 5 frames at maximum bend only, in this instance, gives a false reading..
The other vaulter I emailed you jumping 5.90 is a case of “stop” action.. which created his tuck and shoot.. and if you compare that vault you will see he is way below the “back flat” position at maximum bend AND the pole has stopped moving toward the pit.. only his superior speed on the run allowed him to grip the same as Tim and jump the same height as time.
dj
--very slowly.