- Lavillenie gibilisco and Bubka all slightly under take-offs.jpg (85.99 KiB) Viewed 10023 times
- Damiel DOSSEVI - 5m60 attempt sample of his technique part one..jpg (94.45 KiB) Viewed 10020 times
Above to assist my previous post and your deliberations.
The critical issue to be resolved, in my view, is how the athletes are solving the initial energy / momenta exchanges during the impacting collision of the pole with the rear wall at the deepest point of the planting box in relation to their take-off point location, grip length along the pole, pole stiffness and the pole chord angle that remains to travel through before the vaulter plus pole reach the plane of the crossbar.
The efficiency of the energy exchange and momenta transfer at the final velocity and COM height above the runway of the vaulter is determined by the energy losses during this pole -box and the pole-vaulter collisions. How does the vaulter optimise the take-off and , yes, MINIMISE energy wastage is the question to be answered before proceeding to subsequent stages of pole support?
Boiling my answers down to essential take-offcoaching points expressed in as few words as possible.
My take home messages for the take-off:
1. Max CONTROLLED approach run Velocity KEY WORDS ACCELERATE SMOOTHLY
2 .Accurate High Pole Plant KEY WORDS BOTH HANDS HIGH
3. Jump Up to Move the Pole about the tip in the box KEY WORDS: JUMP HIGH (technical analysis shows foot plant and roll on to toes technique is very efficient).
4.DRIVE the pole and SWING No STOPS from Toe off till Pole release KEY WORDS: GRIP and DRIVE
5. Make initial swing Kick so STRONG,LONG and FAST that top and lower arms grips KEY WORDS: [u]WHIP LEG LONG n STRONG
6. PULL against the bend of the pole[/u] (Controversial but some thought about mechanics shows this must according to physics be true once the take-off toe tip is off the ground!) KEY WORDS: AMP UP THE ARC of SWING . AMP = Amplitude.
Note: No instruction given about pole bend at all or anything about the lower arm action during or immediately after take-off. Why not? It just isn't necessary and misdirects the vaulter from accomplishing the purpose of the vaulting challenge!
Many Old schoolers just find this mystifying.Rethink the challenge and reapply the physics on how to efficiently rotate the whole system without stalling at any stage in the process and perhaps you will see through a glass less darkly!
Note: Despite the old belief that prolonging ground contact time will enable vaulters to generate more initial pole bend and effective jump impulse, the research shows this to be not true in practice. Many Elite vaulters tend, as they become more proficient and have longer pole grip lengths, to reduce take-off ground contact time as their run up speed increases.
High final approach run speed is necessary but not sufficient to differentiate between vaulters who are World Elite standard despite correlating positively with higher bar clearance .
(Correlation is the association between the numbers representing the co related variable comparison and the relationship need not be causal. There is less range of variability in the standard of elite vaulters which also reduces the extent to which correlations necessarily can be used for predictive purposes).
What has this thread added.
Nothing New or Unknown Added
Strong Points
Always consider the cost benefits and recognise individual differences in vaulters capacities and abilities.
Science
If the facts input are wrong the conclusions are very likely to also be wrong.
Yes, the vault is complicated. But it can be simplified allowing the coach and vaulter to act with confidence by asking the right questions on the basis of reasonable facts.
Vaulting Technique Efficiency.
My biased assessment.
Mostly about the wrong question because the focus has been on the vaulter and not the primary challenge to all of the work (useful v useless) that a vaulter must do.
Successful jumping using a flexing spring device is fundamentally about how the vaulter plus pole ,as a total system, can be rotated about a pivot point so that temporarily stored energy in the spring is returned to an inverted vaulter at the point in space and time that optimises the vaulter's work and achieve legal passage across the bar.
Focusing on what the vaulter does about the remote centre of rotation of the vaulter and ignoring the work of the total system COM about the global system centre at the pivot point in the box leads to complex often misguided or wrongly directed solutions to the vault challenge. There are no "style" points in pole vaulting but efficient effort is key to success, while wasted effort leads to the dustbin of history at best and at worst the grave.
Lavillenie technique is not "radical" and I have produced evidence to support my thesis that as Renaud grips at a greater length along the pole and progresses to jumping on stiffer poles, because of the challenge imposed to the total system (vaulter + Pole) ,he is evolving his technique at take-off to resemble, at this stage of the vault, a Petrov - Bubka Method trained vaulter.
Why? Because the "Old French School Type "under and initial force bending method" of take-off is too great an impediment to achieving successful take-off energy and momenta input using this method. He must take-off further out as his grip length on the pole increases.
Reduction in the pole chord ground angle this entails increases the probability of the total system stalling out before it reaches close enough to the plane of the cross bar with sufficient energy from pole recoil to give him sufficient final kinetic energy in the horizontal and vertical direction or sufficient whole body rotational kinetic energy about his COM to clear the bar.
It is my contention that the Risks of failure using a technique that causes the early pole recoil inherent in the Old French Technique and his stature limitations necessitate the change we now see emerging in his take-off technique.
Nothing new or revolutionary, Russian or French!
Dare I say it, plain old common sense really.
Explaining why is not an easy task even if I am an Anglophone.
Physics concepts (mechanics) in my view using classical foundations , especially dynamics if applied properly, are sufficient to un ravel the basic facts for Vaulters and Coaches who still actively pursue their passion for the event in what is after all a Newtonian World.
The world of "Chaos Theory" fascinating as it may be to mathematicians and theoreticians does not hold a candle to just "doing it!"
Finding out what works and what doesn't by running, sticking the pole in the box and jumping is so much fun and excitement, that KISS is easier and progress is faster. We all know this.
I contend the more you know, the more the simplicity of the event reveals itself.
Understanding intellectually is one thing. Expressing that understanding though personal actions is also very revealing of the amount of wisdom from experience required to sort pole vault science from the fiction.
Wisdom is not an emergent state property of inert navel gazing.
