ideal technique in the fiberglass vault

[david bussabarger]

In response to Pole Vault Student,
Thanks for your excellent response. You must understand that being a minority of one on this site means that when I post an "article" I am overwhelmed by negative responses and cannot read through and respond to all of them. So I skim read them and then respond.
In my article I propose that if we are to approach vault technique scientifically (using Darwin and Hubble as examples to follow ), then the technique of a large number of elite vaulters must be throughly analyzed and conclusions must be sorted out in an organized fashion ( i.e. what are the common denominaters and what are the variables ). This is what I have been doing for decades and what my ideas on the vault are based on.
As a result of my studies, I do not believe in one ideal theory of technique. Realty or empirical observational evidence of champion fiberglass vaulters throughout
the history of the event makes this assertion virtually unassailable.
In regards to the take off point: based on empirical observation it is my conlusion that there is a "functional take off zone" that varies from vaulter to vaulter. Excellent results have been achieved taking off 3 to 4 inches behind the vertical plane of the top hand when the vaulter is in a vertical postion before leaving the ground ( and the tip of the pole is secured at the back of the box ). Historically this goes back as far as the early 60's. Good examples are Manfred Preussger and Klaus Lehnertz. Typically, vaulters who take off out have a free-take off ( as Preussger and Lehnertz did ). So the free-take off is nothing new and has been around since the being of the use of fiberglss poles.
On the other end of the spectrum John Pennel and Fred Hansen were problably the first champion fg. vaulters to take off under. I hope no definition of this term is needed. Hansen took off extremely far under. My guess is about 20". When looking at 6m or better vaulters many of them take off under( Mack, Stevenson, Lobinger and so on). At the exteme end Ecker, Brits and Galfine all took off around 18" under. Hooker and Hartwig often, but not always, took off slightly under. I find the studies that state that taking off under is a flaw because it reduces take off velocity dubiuos. I think these studies are missing the point. The critical factor in the take off is how much pentration force a vaulter generates during the take off. An analogy can be drawn from boxing. Boxers with the most arm speed are not the heavist hitters ( think Ali vs Foreman here ). A vaulter can take off under and still be able to generate alot of penetration force.
In regards to Lavillnie's take off: He is an outstanding example of a vaulter who generates tremendous pentration force, so having a lower angle at take off doesn't affect him much. The ability to generate great penetration force during the take off with fg. poles has allowed small men to reach elite levels of performance going back to the early years of fg. vaulting. An outstanding example here was Claus Shiprowski, oly silver medalist in 68 at 17-81/2, 1/2" under the world record at the time. Ship. had a top grip of about of about 15-8, which was as high as anyone at the time. He was only 5-9 3/4 and like alot of vaulters of this period used a very low modified rigid pole plant. He also took off about 18" under. The point here is he had an extremely low angle at take off but was the 1st vaulter I know of to really exploit the development of pentration force during the take off.
I hope I have answered most of your questions. If not, let me know.

[KirkB]

A major issue with any scientific analysis of competing "PV models" is that there's so many variables involved. There is the technique itself (and all its variants - not easy to classify or quantify), and then there's the physical attributes of the subjects (such as speed, height/reach, weight, strength, body shape, age, years-experience).

There are also some intermediate variables, which are strongly correlated to competing techniques as well as the subjects' physical attributes (such as pole stiffness, grip, height of top hand on takeoff, distance of takeoff from box). Some additional variables can be computed from these (such as angle of pole on takeoff, push-off, or strength-to-weight-ratio).

The aspect of time - beyond just speed on takeoff - adds another set of variables (time between takeoff instance and pole striking box - can be negative or positive; time from takeoff to start of swing; time from start of swing to end of downswing - when trail leg passes the chord; time to reach flat-back position; time - or speed - thru the flat-back position; time to full body extension; time from full body extension to release of top hand; time from release of top hand to maximum CoG/hip height). Note that some of these timings can be combined - for example "time on the pole" would be the time from takeoff to pole release. I believe that DJ has already done quite a bit of research on this.

I think the timing aspect of any PV technique distinguishes one PV model from another even more than the physical measurements taken in the absence of a time element. It should be obvious that you cannot just hang on the pole and let it propel you over the bar, because (a) you also need to be inverted during this propulsion (or you will flag out); and (b) the longer you wait for the pole to propel you the longer gravity will affect your flight-path on and above the pole. i.e. If you delay too much, then gravity will "take over" too soon.

The Continuous Motion Theory advocates (I'm one of them) stipulate that there should be no passive phases in the vault - you should eliminate all passive phases, and you should ALSO speed up each active phase to the max. There are limits to this of course, because the timing has to be in unison with the coiling and uncoiling of the pole, but (for any technique) it's much more common to be "too slow" on the pole rather than "too fast".

There have already been many scientific studies performed with many of the aforementioned variables. The challenge is to pick the BEST variables, and to use those in benchmark studies or comparisons of alternate PV techniques.

Another challenge is that Bubka was the fastest vaulter of all time, and also (arguably - apparently) the best technician of all time. Therefore, we cannot even seem to settle on the CAUSE of his WRs - whether they were caused by his speed or by his technique. Clearly, BOTH were significant factors in his stellar clearances, but to what proportions?

Suppose we zeroed in on a single key variable - the speed of the vaulter at the instant of takeoff. The second variable would be the height cleared. The third variable should be a particular aspect of a PV model that is under debate. This could be the "time between takeoff instance and pole striking box", or it could be the "speed thru the flat-back position" or the "time on the pole".

Most of the discussion on this thread thus far has been about the former, but in terms of differentiating a Tuck-Shoot technique from a Petrov technique, I think "speed thru flat-back" might be even more revealing. Also, even with the naked eye, it's quite apparent whether there was a delay in the flat-back position or not, whereas it's not as apparent exactly how/when/where the subject's takeoff foot left the ground.

The other reason why I'm partial to the "speed thru flat-back" (or "time on the pole") variable is that you just need to count the number of video frames in which the subject is in this position (or phase). And since the flat-back position (or time on the pole) is after the takeoff, it's a RESULTANT measurement, rather than a SOURCE measurement. Thus, by "grossing up", it will take into account any technical advantages or disadvantages (such as a free takeoff) achieved in earlier phases of the vault sequence.

I am proposing that if we fix certain key variables, then we don't have to limit our sample size to just elites over 5.80 or 6.00. From the perspective of young aspiring vaulters and their coaches looking for performance-improving direction (advice based on science - not opinion), it would be highly advantageous to analyze any and all subjects (not just elites) where these key variables are measurable with some degree of accuracy. Takeoff speed is also sex agnostic whereas bar clearances are not.

For simplification (although admittedly not very scientific), a subject's speed on takeoff could be approximated by counting the number of frames taken from mid-mark to takeoff, and dividing by the frame rate.

Furthermore, if the primary variable is speed on takeoff, then any aspiring vaulter (with a video camera at his disposal) should be able to measure his own speed on takeoff, and compare it against a chart of all other vaulters with similar speed, and determine his potential bar clearance if he (for example) chooses to have a free takeoff, or if he chooses to optimize his swing such that his speed thru the flat-back position is improved.

With sufficient raw data as described herein, there should be "clusters of technical excellence" that begin to become obvious on a two-dimensional plot-chart of speed v. bar clearance. Each data point can be shown in a contrasting color for each discernible variant (such as flat-back values over/under a certain threshold).

Note: Video camera frame rates vary - they are usually 24, 25, or 30 frames per second. Once the frames are counted on a certain camera for a certain variable, they must be converted to meters per second based on the frame rate.

Kirk

[KirkB]

As an avid proponent of The Continuous Motion Theory, I have now updated my tagline accordingly!

I'm actually not against tucking. Even Bubka tucks a bit (ever so slightly), once he finishes his downswing. It's the pause at the end of the tuck that I'm against.

Tucking actually speeds up the rotation of the body - to invert faster. However, most (not all) tuck-shooters tuck way too early - losing some of the power of a fully-extended trail leg on the downswing.

Ironically, if they had a more powerful downswing, they wouldn't even need to tuck much at all!

Kirk

[david bussabarger]

I would say that the complexies and variables are so great in the fiberglass vault that technique can potentially evolve and improve indefinately. This why I object so muuch to the claim that the p/b model represents ideal technique. If eveybody believes this, technical evolution comes to a dead end. Fortunately there are still a few independent thinkers around in the vault world. I love Leonardo Da Vinci's motto: "never let what has come before you limit you" ( this goes for both thought and action ).
Bubka was not only the fastest vaulter of all time, he was also the most explosive in terms of the execution of his vault. In my view, this was also a key factor in his ability to dominate the vault . Note that Launder vociferously denies these facts. The claim that Bubka's technique was good, but not ideal is backed up by the fact that:
1. The next best mark by a vaulter who closely fits the p/b model is currently 19-5 by Dean Starky, a very good mark but FAR below Bubka's pr of 20-2. Note that I do not include Tarasov here because he had a prounced stiff arming action during the take off and swing which violates a key principal of the p/b model.
2. The ideas of the p/b model have been around since the late 1970's, yet in all that time it has not produced even one vaulter who could even come anywhere close to Bubka's wrs. I would agrue that Hooker and Lavillenie, the most notable challengers to Bubka, both have
their own style and are note b/p vaulters.
A final point, it is commonly stated that the swing of tucking vaulters is inferior to that of vaulters successfully employing a continuous sweep to the completion of the r-b. I suggest that somebody time the swing speed of elite tuckers to elite swing-back vaulters. This would have to be based on the maximum velocity developed during the swing. This point should occur when the extended trail leg reaches alignment with the axis of the pole. I would bet that Gibilisco's max. swing velocity is greater than Tarasov's and maybe even Bubka's, for example.

[KirkB]

Moving this post to the end of the thread. I didn't mean to insert it here.

Kirk

[KirkB]

David, what do you think of my first proposal - to measure the difference in flat-back time and use that as a differentiator in plotting Tuck v. Petrov subjects on a graph of Takeoff Speed (on one axis) and PR (on the other axis)?

It sounds to me like you're actually challenging my premise, and you don't think we'll find any differences in flat-back times between Tuckers and Petrovers?

Kirk

[KirkB]

Shall we start with the PRs for each of Gibilisco, Tarasov and Bubka?

On second thought, I think we should first compare an obvious Petrover to an obvious Tucker with an "in" takeoff. Like Bubka v. Brits?

Kirk

[PVstudent]

Thank you David for your reply.

I shall just say that at the moment that there are quite a few things in your reply that I find both interesting and subject to considerable debate though worthy to explore further.

For example in relation to penetration force. This could be penetration force acting on the vaulter, penetration force acting on the total system centre of mass. By penetration force are you referring to the horizontal force component acting on the total system centre of mass at the instant of take-off or for example at maximum pole bend or both?

However I would like you to address the specific example of the video recorded images that I specifically provided and the still images also provided. By doing this everyone reading the thread will be dealing with the discussion from the same empirical evidence base.

Remember that the majority of readers only know the names of many of the vaulters you refer to and will not have had access to film or sequence photos that were used, for example, in the many editions of "Mechanics of the Pole Vault" by Dr. Richard Ganslen.

The matters you and Kirk raise though fascinating, and perhaps relevant, the central issue in your criticism of ideal models in coaching and elite vaulter performance is not being explored.

As I have stated I am open to being convinced that in the coaching and teaching of the take-off in pole vaulting that I have been wrong in my fundamental belief that the central tenet of the Petrov/Bubka Model "The Free take-off" is more efficient in redirecting and conserving momenta. It is able to do this, I believe, because it takes into account individual variation in take-off foot toe-tip placement relative to the rear wall of the planting box due to size (stature in particular) of each vaulter and their grip length from the pole tip to their top grip hand.

Once I, and I hope other readers, have your answers reflecting your perspective on the specific examples then I think we will be able to communicate clearly to find shared common ground and find rational reasons to argue/debate/discuss the issue in language and terms that are mutually agreed and understood.

Kirk I think perhaps you are being somewhat hasty in your enthusiasm and if you review the scientific literature, scanty thought it may be, the answers you are seeking have been partially provided. What has not been done is to actually make the direct comparisons between the individuals you and David cite.

By consulting the IAAF Biomechanics studies that have been carried out you can probably make a pretty good comparison between Bubka, Tarassov and Starkey.

The comparisons you specifically want to make are not quite as straight forward as you imagine. Yes, video can be an excellent timing device but you will find that the source video unless taken from the orthogonal side on view and at the same original film speeds and then converted to Quicktime for analysis the measurements made can only give "ball park guesstimates" at best.

I think the results would be interesting and generally informative and possibly worth while doing. Before I would be prepared to conduct such a study I would want to be sure that the variables I decided to measure were the appropriate ones needed to answer the question being asked.

At this juncture I am still eagre to have my specific questions about the specific examples I put up answered by David or anyone else who might be prepared to do so.

I think David has, by playing Devil's Advocate, gone more than a few steps too far and I want to be perfectly clear about what he is trying to communicate and ensure that I come to know whether I really disagree/agree with him. More importantly I will know the reasons why I agree or disagree.

In a sense David's position is a good one in that;

"Only those who will risk going too far can possibly find out how far one can go"
T.S. Eliot

In the meantime I will await further clarification.

[KirkB]

Kirk I think perhaps you are being somewhat hasty in your enthusiasm and if you review the scientific literature, scanty thought it may be, the answers you are seeking have been partially provided. What has not been done is to actually make the direct comparisons between the individuals you and David cite.

By consulting the IAAF Biomechanics studies that have been carried out you can probably make a pretty good comparison between Bubka, Tarassov and Starkey.

I'm not aware of the IAAF Biomechanics studies, but I am aware of the articles published by Nicholas Linthorne and by Dr. Peter McGinnis (unless McGinnis is the author of these IAAF studies that you refer to). As I mentioned, I'm also aware of David Johnson's work (a collection of PV statistics), but I don't think he's published any articles on it yet, or drawn any conclusions based on his analysis of the stats yet. DJ?

Also, the one unique idea that I was adding to the mix here was to create a "scatter-plot" of Takeoff Speeds v. PRs (which has already been done by the aforementioned) but ALSO differentiate each subject by whether they are classified as a Petrover or a Tuck-Shooter (based perhaps on the "time on the pole" but particularly based on "time in the flat-back position"). As I mentioned, by color coding the resultant data points in contrasting colors, with a statistically significant sample size, these dots would reveal the trend of each model!

Do you agree that this idea hasn't been published in any scientific articles yet?

The comparisons you specifically want to make are not quite as straight forward as you imagine. Yes, video can be an excellent timing device but you will find that the source video unless taken from the orthogonal side on view and at the same original film speeds and then converted to Quicktime for analysis the measurements made can only give "ball park guesstimates" at best.

Yes, I anticipated and I accept this criticism. I'm also concerned with the identification of the precise frame where each phase begins and ends. I have done this on numerous occasions, and sometimes (unfortunately) the timing of the frames is such that the precise moment in takeoff is maybe halfway between one frame and the next. So the level of accuracy may be only plus or minus a frame - at best. Do you have a more scientific alternative? I'm all ears.

I think the results would be interesting and generally informative and possibly worth while doing. Before I would be prepared to conduct such a study I would want to be sure that the variables I decided to measure were the appropriate ones needed to answer the question being asked.

Agreed.

To be fair to Dave, I think some of this is new to him, and I think he's listening with an open mind - almost.

Kirk

[david bussabarger]

Reply to vault student,
I'm not completely sure what you are asking me to answer. I'm guessing it involves the efficacy of the free-take off. As I stated ,empirical observational evidendence proves that many vaulters, throught the history of the fg. vault , have achieved great success with a free-take off action. What I strongly disagree with is the THEORY that the free-take is an ideal technique that everybody should strive for. There is no empirical evidence that supports this theory other than Bubka's singular unmatched success. However, even Bubka took off under some of the time with great results. I have many vids of Bubka and the most impressive one I have of him is his w.i.r. 19-1 1/2 in 84. On this vault he takes off about 1' under and soars over the bar by a foot or more. This is not to claim that taking off under is superior, only that it is a perfectly viable option as long as the take off point remains within functional boundries ( the take off point is not excessively under ). In otherwords, according to my analysis, the take off point is a variable aspect of the technique of elite vaulters, not an invariable aspect as is claimed by p/b advocates. The mistake that p/b supporters make over and over is that they advocate theories that are not supported by what the great majority of elite vaulters actually do in the real world ( empirical evidence ). This is completely unscientific.
By penetration force, I mean the inward force of movement of the vaulter's body ( particularly the c.m. ) generated during the take off. Given correct execution, this force is directed both into the pole, generating pole movement and bend, and into the vaulter's subsequent swing. One of the most important advancements in fg. technique over the years has been the improvement of the development of penetration force during the take off. This has allowed vaulters to raise handgrips to current levels while retaining equivalent push-off distances achieved by early fg. vaulters with much lower grips. Note that Seagren gripped 15-1 on his 1st wr in 72, 5.60m ( push-off of 3'-11 1/4" ). A critical point in the development of penetration force was simply controlling posture and hip position during the take off. The hips of virtually all early fg. vaulters ( with the exception of J. Pennel ), curved upwards very rapidly during the take off. Good examples are Sternberg and Hansen. As a result very little horizontal force was generated during the take off. J. Johnson and D. Roberts pioneered the development of penetration force in the early 70's. Note that I consider previously mentioned C. Schiprowski an historical anomaly. His technique had no real infleuence on succeeding vaulters because his career was so brief. In adition to improved posture, both Johnson and Roberts actively pressed their torsos inward during the take off. If you compare the number of frames Johnson's and Robert's torso's move inward during the take off on vids, they move inward mush longer than any other top vaulters of the sme time period.

[IAmTheWalrus]

David,

No one that I am aware of is arguing that you can't be successful with an inside takeoff, tuck,etc. I am not even going to argue that a free takeoff is superior (or any other p/b element). However I will continue to state that your observations do not support your conclusion. That is my only true point of contention.

A. Empirical evidence suggests that vaulters can achieve extraordinary marks (>5.80m or even 6.00m) with inside takeoffs, tucks, stiff left arms, etc. TRUE

B. Empirical evidence proves that there is no optimal technique. FALSE
- The empirical evidence certainly does raise questions, and invites a proper study.
- A proper study would include controlling as many variables as possible and isolating the variable in question (p/b model, or better yet, one element of that model (e.g. free takeoff)

C. The Petrov model is proven to be superior/inferior. FALSE
- Insufficient information, as you have said there are a limited number of p/b vaulters at the elite level that clearly demonstrate all aspects of the model, and I don't think there is agreement on who they are outside of Bubka (most people would include Tarasov over Bubka in my opinion).
- This definition is made more difficult by the inconsistency in exclusion criteria, e.g. if they tuck they can't be petrov, or if there arm is straight it can't be p/b.
- Bubka's success can't be discounted. It is impossible for us to say (especially if we are only evaluating empirical evidence) how high Bubka would have jumped with a different model, or how much of his success beyond that of his competitors was due to athleticism vs. technique.


You repeatedly mention how proponents of the P/B model are ignoring empirical evidence and science, but you are drawing conclusions well beyond the implications provided by your empirical evidence. An equal if not greater demonstration of scientific ignorance. Your opinion/theory is that there is no ideal model is a valid opinion/theory. I understand that you are basing this on what you have observed. Also valid, but it has no more merit than any other untested theory. In order for your theory (which I don't think is new, nor does it represent "rebel thinking," just go to a collegiate track meet or practice. So many different models and styles are used in America) to become accepted it must be tested, as PVStudent state, with an attempt to disprove it. The fact that there aren't many elite vaulters using the p/b model doesn't indicate that it is a bad model; it implies few people are able to put in the time/effort to master it!

[dj]

Hey,

The swing speeds of most if not all of the 5.90 to 6.00m jumps I have checked, mostly done by McGinnis have been in the 1.45 sec range from takeoff toe about to leave the runway to max height of the COM.. Tucked and none tucked were no different...

Ie Tim Mack v Jeff Hartwig

Jeff, on his best jumps went "through" the tuck faster than average jumps...

An interesting thing about the "physics" of the vault is a 20 foot jump by Bubka or Tim Mack takes much less time to complete than the average 14 foot high schooler...

Time times distance... Yada.. More force .. A faster swing over a greater distance (higher grip) produces.... Force to move that grip and pole to vertical...
Dj