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Volteur,

i should have called it relative weight then, yes? It radically increases after this 45 degree angle.

No. This is quite wrong!
Consider the vaulter running in the direction left to right. Imagine the start of the run (for the purpose of clarification) the pole is held at 90 degrees to the right horizontal. Before there is any inclination of the pole away from the vertical the weight of the pole (pole mass x gravitational acceleration) is supported by the vaulters contact on the pole and the weight acting vertically downward mid way between the shoulders on to the torso. There is no torque created by the pole at this stage because the pole is vertical.
Now consider the run with the pole inclining in the direction to the run way. The more the pole moves away from the vertical the greater the horizontal distance away from the supporting axis to the vertical action line of the pole weight . This increase in distance makes the weight of the pole produce a greater turing effect of the pole about the axis of support. Pole weight force x horizontal dist to axis from the line of action of the weight creates a torque (turning or rotational effect of a force acting at a perpendicular distance from the axis).

The further the pole moves away from the vertical and the line of weight force action from the axis, the larger the torque becomes. This continues until the pole reaches a horizontal position above but parallel to the run way. At this instant the torque applied by the pole is maximum.
(If the arms are not being forced forwards or backwards in a pumping action -not desirable- and the pole support axis has not been changed my explanation holds).
After the pole has continued to move further away from the vertical and is below the horizontal the torque created by the weight of the pole is reduced slightly and continues to reduce until ground contact is made.

Forward and backward pumping action in the run serves to alternately increase and decrease the torque due to the pole weight and causes impulsive jerk on the pole and reduces pole drop smoothness of motion.

So, all other things being held constant, the torque created by the inclination of the pole increases until it has passed throught a 45 degree angular displacement from the vertical and subsequent to that point is reduced.

I do disagree that the left hand (R-hand vaulter) sits directly in front of the sternum. It sits to the right of the sternum. I agree with you that an overly wide grip exacerbates the asymmetry. I also have to disagree with a 3 stride plant (unless you mean the third stride is actually the 4th last stride. The plant begins 4 strides out

I think we will have to agree to disagree about the hand placement with respect to the sternum. You are correct the 3 step plant does indeed begin the 4th step out!

I think before I go any further with this let me suggest the issues the above raises should be discussed on the plant and approach thread. There is much to discuss and unravel.

I would like to get back to the mid mark thread and continue with DJ's chart discussions because I feel valuable as the above discussion might be it will detract from what is beginning to emerge in explanation of the science underlying the chart.

I am happy to discuss the plant technical issues under that thread.

Volteur this thread will be fine could you call it pole plant technique instead of just the pole?

here is that thread.

PVStudent to continue

Firstly i think a few definitions may help as we may just be disagreeing about terminology

Weight - is a measurement of the gravitational force acting upon an object. The objects mass combined with the gravity acting upon it. Not only is it a formula of the physical sciences, it is something we can feel. When i use the term i am thinking of what i can feel.

-It changes whereas the mass remains the same. Saying relative weight is me referring to the changing weight of the pole as we lower it. It gets heavier.

A torque - is a measurement of how a force rotates an object around an axis. The greater the force - the greater the torque; and the greater the distance between the force and the axis - the greater the torque. In this case the force is the weight of the pole.

-So the more vertical the pole and the closer it is to the axis (a point somewhere inside the body) the lower the torque, as you have said and weight as i would have also said

- as the pole lowers from vertical the torque/weight increases (although because the pole is supported in front of it's axis some torque is being applied even when vertical)

-at 45 degrees something changes and we feel the weight of the pole far moreso. You did say toque increases to horizontal at one point and it diminishes after 45 degrees at another. Typo?

-the way i see it from vertical down to 45 degrees, more of the weight of the pole is heading downwards than backwards, and from 45 degrees to horizontal more is heading backwards than downwards. We of course stabilise against these backwards and downwards directions.

How is that so far?

I'm glad we agree with the four stride plant, it was one of the points i wanted to talk with Agapit about from BTB.

I wonder how we can discuss about the ideal position of the left hand?

cheers

Volteur

PVstudent wrote:Volteur this thread will be fine could you call it pole plant technique instead of just the pole?

How is that instead?

So, all other things being held constant, the torque created by the inclination of the pole increases until it has passed throught a 45 degree angular displacement from the vertical and subsequent to that point is reduced.

I was a bit rushed in putting this up I meant the pole must displace throught an arc of 90 degrees from the vertical and at that point would be horizontal but parallel to the run way. After passing through the horizontal and continuing to rotate towards the runway the torque produced by the weight of the pole is reduced. In the pole angle change from the vertical to the horizontal the torque due to the pole weight increases.

The actual maximum torque exerted by the weight of the pole is also influenced by the location of the hands with respect to the shoulder position. Leaning shoulders and torso back from or in front of the hips also influences what this actual maximum will be. Body posture vertical alignment is an important contributor in how effective the vaulter is in performing the plant action freely and smoothly throughout the plant process and in using this torque to assist in the increase of final 3 step cadence.

To discuss the plant fully and to ensure we are speaking unambigously within a shared language and conceptual framework we might start with a definition of what action starts the plant, where this start occurs and when precisely a plant action can be recognized as occurring.

Note that the reference framework should be that of the external observer because the kinaesthesis (the feeling) of the actions experienced by the vaulter need not necessarily be temporally or spatially in exact agreement with what is observed by objective means (film /video/ force platforms etc)used. Also the kinaesthesis of the vaulter is unique to the person and there is no definite way to prove or falsify (in the Popperian sense) this form of description.

Since I am a 'Petrovian' by training and hold the belief that the 3 - step plant gives the vaulter more time to optimize plant effectiveness to achieve efficiency of momentum and energy transfer in the takeoff my preference is to limit the discussion initially to the 3 step method.

Where to from here?

Here are some points re definitions and setting a base for talking in the same way about the same things.

The Approach Run (or run up)

Is the running sequence starting from the initial forward step of the vaulter, in the direction horizontally along the runway towards the vertical plane of the pole vault crossbar, and ends at the first discernable touchdown contact of the foot used to execute the jump takeoff. Usually the approach run comprises an even number of running steps with the first step being made to land on the non takeoff leg foot (right leg for a right hand top grip or left foot for a left hand top grip) and the final step to land on the foot of the takeoff leg.

The 3 - step Plant culmination of the approach run. (description for a right top hand grip and left foot takeoff)

The 3 step plant is considered to have the following foot contact and step flight pattern:

(4th last foot contact)Right Foot Toe Off and Flight phase to land on
Step One of Plant
(3rd last foot contact) Left Foot Contact Touchdown The wrist, elbow, shoulder actions to initiate the plant have just commenced at initial touchdown of the left foot. Left Foot Toe Off and aerial flight phase to land on
Step Two of Plant
2nd last (Penultimate Foot Contact) Right Foot Contact Touchdown and plant movement sequence has progressed to where the vaulter's right wrist has moved slighty forward and upward to a position just above or at vaulter head height. Right Foot Toe Off and aerial flight phase to land on
Step Three of Plant
Last (Takeoff Foot Contact) Left Foot Contact Touchdown the pole tip contact with the planting box apron may occur at this instant or a very short time after this. Both the vaulters arms continue their primarily upward motion of the plant action until interrupted by the pole tip impact with the rear wall of the box.

The plant (approach run phase) is considered to be completed and the takeoff (culmination phase of the plant) commenced at about the end of the braking component time of the takeoff foot contact with the ground and initial pole tip contact with the planting box. During the small time of the pole slide in the planting box and the vaulter's upward spring the plant arm action continues upward so that culmination of the plant occurs at or just after the the toes of the takeoff foot can no longer exert downward or horizontal forces against the ground.

More to follow.

Volteur, I hope you can agree to using weight as a concept of force and not an indication of the "heavyness" experienced in handling an object.

The sensation is not directly equivalent to force as it is influenced by many other considerations (a silly example but 1 kg of jelly, 1 kg of feathers, 1 kg of gold all have the same weight but the sensation( kinaesthetic) experienced in trying to lift or handle them will be quite different).

Can we agree to use torque and weight according to mechanics definitions?

Sorry i haven't replied sooner PVstudent, the first couple of times i glanced at your posts it was 'whoa i better take this seriously', so here goes

1. I agree with your statements on official definitions of torque and weight and my own definition of weight. So in order to be clear i will always use that definition of weight in italics from now on, as the thing we can feel from the pole, pressure or heaviness or whatever. I wish to retain this feeling/sensation aspect because, even though it might be found subjective in comparison to a theoretical discussion, in my opinion individuals often share their subjective experiences, and often in quite intricate detail. So i hope we can refer to that sort of thinking as well as theorise the crap out of this.

This would need some agreement as i don't think i can go through a completely theoretical discussion. I guess i would be happy in trying to cut into some of this theoretical mess by connecting general experiential knowledge with theoretical knowledge so we can sort of the 'wheat from the chaff' as they say.


2. The plant begins when? I think you are saying at touchdown of the third last footfall or at the end of the third last step. Is the general rule a two stride plant?

I would say the planting action begins on the uprise just prior to the toe off of the fourth last footfall ie off the right foot for a right handed vaulter. This is where the right hand begins to rotate and rise and the right shoulder etc adjusts for this -- or maybe it is the other way around?

3. prior to the plant we have the continuous lowering of the pole from its near enough to vertical starting position. In this phase of the vault we have the first step ie initiation of movement, the progressive acceleration of the run-up to this 45 degree angle and then usually two strides till the plant begins - from then on there is another two strides before the pole is horizontal and then a further two before the plant is completed.

Sorry i ignored the specific steps of the plant for now it is just that so much happens to the pole prior to even the plant and i would like to go into that stuff initially - sort of in a timeline. Still i wonder whether you agree or not with that timing of the plant?

There are also a few other things that might or might not be agreed upon. Firstly, the continuous lowering of the pole. Secondly, the progressive acceleration of the runup which leads to a progressive acceleration of the takeoff. Thirdly and maybe most importantly, that precise starting point of the planting action.

cheers

Volteur

I am not theorizing it is just that the use of carefully defined and used words will simplify the connecting of "experiential and theoretical knowledge". In a sense, since one cannot be privy to what is actually a thought in another person's mind, all written or spoken discourse is theoretical.

I cannot accept your use of the term relative weight as the equivalent of torque induced load because weight is merely a force, or a mass accelerated downward vertically (towards the center of the earth) whereas the torque (due to the weight force) causes the mass to be accelerated in a circular path about an axis. Whilst the two effects may feel the same at any instant for the vaulter they produce entirely different motion consequences. There is nothing theoretical about this need to differentiate between weight / relative weight force and torque because the motion descriptions of the vaulter and the observer of the actions of the vaulter will confuse rotation and linear translation.

I prefer to be specific and hence I refer readers to the accompanying PDF file as I answer the points you raised for clarification. (pdf at THIS LINK)

Firstly let us be clear. I am using the term step and I do mean step and not stride.

A stride is defined as the ground horizontal distance travelled from a foot breaking contact with the ground until that same foot next makes ground contact ( ie from Toe - Off (foot breaks contact with the ground) distance covered from that point on the ground to the Toe Touchdown point of that same (ipsilateral) foot on the ground ).

A step is defined as the horizontal distance travelled between a foot breaking contact with the ground and of the other (contralateral) foot contact ie Toe - Off from one foot to Toe Touchdown of the contralateral foot.

The 3 step plant: (defined according to the timing of the action of the arms synchronized to the declination of the pole from about 10 degrees above the horizontal until the pole tip contacts the planting box).

starts (for right handed vaulter) in the late portion of the aerial flight phase from 4th last foot contact on the right foot to continue through to the (1) left foot ground contact followed by (2) right foot contact and finally

ends on the (3) left foot contact (the last or jump takeoff foot contact: initial braking phase through to mid stance) when the pole tip contacts the planting box.

(Use the scroll bar next to the graphs/images to see the bottom portion.)

If the plant is to be defined according to the point in time where the vaulter experiences an increase in the rate of pole declination from the actual 65 - 75 degrees pole carry angle above the horizontal in the initial phase of the approach run, the plant could be considered to start between the 11th and 10th step touchdown out from the takeoff. However the rate of pole decline towards the horizontal increases rapidly from the 7th step touchdown out from takeoff. This could be argued to be the start of the plant phase using the rate of pole declination speed rapidly increasing as the referent. From the coach's perspective it is much easier to recognize and note the commencement of the plant initiating action of the arms at or immediately prior to the 3rd last foot touchdown! From the vaulter's perspective the pole declination acceleration between 7th and 6th last foot touchdown acts as the cadence increase stimulus and the setting up of the postural orientation and readiness to initiate the arm action properly timed and synchronized to the pole dropping rate and foot ground contact on the 3rd last foot touchdown. Once initiated the arm action proceeds at a rate in the (predominantly) hands upward direction in harmony with the step length, rate and trunk posture of the vaulter until about midway through the stance phase of the final ground contact when the pole tip makes its initial planting box contact and the take - off starts.


Models of what I call the 3 step plant is shown in the PDF file slide sequences taken from competition performances of Bubka, Johnson, Markov, Gibilisco, Tarassov,Feofanova, Isinbayeva and the left handed Becker.


I offer these examples to give a clearer viewing of the spatio - temporal aspect and the plant movement sequence used.

Volteur, I suggest that careful examination of these models will show that your description of the timing of the initiation of the plant action (with arm action initiation) is quite wrong in these individual cases.

The striking aspect of the evidence I present is the high degree of movement pattern similarity between the vaulters!

I deal in this post exclusively with a precise definition of the 3 step plant and identification of a consistently recognizable start point for the plant process. My evidence is in the PDF file and the vaulter performances as shown. Note that the photo sequences are all produced from competition footage and includes Isinbayeva's most recent WR of 5.03m.

The definitions are not theoretical but reflect what I believe the exemplars actually demonstrated in the particular pole plant actions depicted.

A case can be mounted for the start of the plant as occurring as early as the 7th last foot touchdown whilst I consider a plant starting later than the 3rd last foot touchdown to be less than optimal in achieving the functional objective of the pole plant.

(I am not prepared to mount that case as I am advocating the 3 step plant as being not only easily recognized but practically usable by both vaulter and the coach in ensuring efficient, precise and consistently reliable entry into the takeoff).

The functional objective of the "pole plant action" I define as:

The function of the pole plant is to enable the vaulter to arrive at the takeoff with a body configuration and pole orientation angle placement in the planting box that optimizes the transfer of the final momentum and energy of the approach run into a takeoff that can minimize total system energy loss whilst maximizing the potential and kinetic energy imparted to the vaulter pole system at take - off. Efficiency in directing the vaulter - pole system towards achievement of the ultimate goal namely maximum bar height clearance by the vaulter must also be achieved as a consequence of the plant action used.

I am open to alternative interpretations of the evidence I have put up. Still frame photos cant tell the full story. I would like to know if I am perceptually blinded by my bias in viewing the original footage and what I reveal is mere chaff rather than wheat!

These images at least can provide a source for honing the accuracy of any 3 step plant action descriptions that hopefully will follow.

Continuous lowering of the pole and progressive accelerations in run up and takeoff remain to be sorted out. Precisely what is meant by continuous lowering and progressive acceleration in the pole drop (declination) and the run remains to be explored and clarified.

At this stage the focus is rightly on identifying where the plant starts and finishes. A full motion sequence description of the plant can then follow when we have achieved some consensus on what we are talking about!

Then it should be easy to identify what an "early" and "late" plant is and to identify their possible causes.

The other issues about the running action in the phases of the approach run could then proceed after the above has been achieved.

Hi PVstudent

nice preparation and thanks for those definitions. Also thanks for such clear argumentation.

PVstudent wrote:I am not theorizing it is just that the use of carefully defined and used words will simplify the connecting of "experiential and theoretical knowledge". In a sense, since one cannot be privy to what is actually a thought in another person's mind, all written or spoken discourse is theoretical.

before i get into the tech stuff this paragraph is filled with good things but i have to argue, this is theorising and we are theorising. Also whilst true we can't be as privy to another persons thoughts as they are, we can get pretty close. When we share an idea we are getting pretty close. A concept sharing even closer. Sharing an experience closer again, although always differing perspectives of course. Empathy is about discovering what another person is thinking or feeling and i think a coach would do well to have empathy for these things in their athletes.

Back on topic and in agreement with you, some words like weight and weight can't be compared because they are describing things from a different frame of reference. Weight is referring to what an object feels like. It is subjective as you said and one persons feel of a particular weight will differ from anothers. Weight is a theoretical objective measurement and can be used for such discussions but not for describing to a 13 year old boy. When i use that word they immediately assume weight and for this reason i use it. It is a word accessible to all. An example is let your weight fall with each stride when you run. Or feel the weight of the pole as it lowers.

It is feeling the weight of the pole as it lowers that is the key to this way of looking at pole vault. You could call it The Way of the Pole. But i do steal from history.

The pole begins at vertical - weightless; and it ends vertical - weightless, from one end of the runup to landing on the pit.

Those jumps we sometimes do - where the pole is left balancing in the box, would be the ideal end of this 'model'. I put the word model in italics because it's not a model but more of a way of looking at the vault. I will explain the view.

Facing the runup from sideways about 50m away watching the pole as the vaulter goes from the runup's first stride to landing in the pit. (landing in the pit is the end of the energy process).

The perfect view of this would be a smoothly rolling pole with no jerks nor accelerated periods breaking it from it's natural rolling action. The rolling action will progressively accelerate until the slowdown as we start to bend the pole with our bodyweight's momentum. During the pole bending phase the cord line takes over as the straight pole line until the pole is straight again.

So what this means is that the plant 'must' begin at a certain point that is determined by the natural rolling of the pole. The timing is determined by the pole.

Any interference with this natural rolling of the pole is taking potential energy away from the vault. Any energy left in the pole at the end of the jump is also lost potential energy. This is why a perfect still and balanced pole at the completion of the jump is the ideal. Never something to focus on, it is the remainer of a perfectly executed jump. Anyway moving on.

I cannot accept your use of the term relative weight as the equivalent of torque induced load because weight is merely a force, or a mass accelerated downward vertically (towards the center of the earth) whereas the torque (due to the weight force) causes the mass to be accelerated in a circular path about an axis. Whilst the two effects may feel the same at any instant for the vaulter they produce entirely different motion consequences. There is nothing theoretical about this need to differentiate between weight / relative weight force and torque because the motion descriptions of the vaulter and the observer of the actions of the vaulter will confuse rotation and linear translation.

I agree with your non-acceptance, i also don't accept but we could get detailed. Anyway as explained above there is the universal idea of weight (heaviness) and the theoretical or scientific meaning of the word weight. Also explained above is the ability for empathy between the observer(coach) and the observed(athlete) and this potential in anyone. But more importantly i don't think there would be any confusion because i don't use biomechanics as a language when i coach. The really interesting bit though is the last part of the last sentence - rotation and linear translation during the plant. How to get this bit correct can be determined by the natural rolling of the pole but this part of it gets tricky for me, however i will have a crack.

As the pole finally pivots over the fulcrum (ie the left hand for most of us) the fulcrum needs to rise and move forward to allow the pole to follow its continuous rolling action. If the pole doesn't move like this it will pivot too quickly. If the left hand doesn't move forward enough as it rises it will cause this pivoting too quickly. If the vaulter does this and is used to the pole pivoting at a speed which is too quick, then naturally they will start the plant later.

*doesn't work for me could you reply to this post and add it and Isi's and Bubka's? Please.

In this sequence Lojo suffers from the above ailment. However, even though this plant is late there is still minimal movement from the right hand as he leaves the ground on the 4th last step. From photo one to two the right shoulder has lifted and the right hand has moved from below the hip bone (greater trochanater) to above it. The planting motion has begun.

Looking at when the plant begins mechanically the right hand will rise with the up-momentum provided by the entire body most easily. As in a clean we get the bar moving with the body and then as the body slows the bar continues it's motion upwards. Same with the pole on a smaller scale. So as we leave the ground the pole is coming with us. All we need to do then is allow it to continue to rise as we descend for the next step. This is why more motion appears to occur during the descent into the 3rd last than from the rise off the 4th last.

Anyway moving onto Isi but i use the side on jump. From first photo (4th last step) to second photo (just after mid stride) her right hand moves substantially and the right elbow angle decreases markedly. I see Petrov all over this. For one she is new to Petrov (compared to Bubka) and so she is overemphasising Petrov's bits, such as bringing the right hand all the way up the right side before pivoting at the shoulder. In Bubka his elbow angle doesn't close as much as this would be more correct mechanically than what Isi is doing here.

Ending with the Bubka black and white sequence things get pretty clear. His right hand rises from pic 1 to pic 2 and his left hand lowers. The fulcrum at this point is midway between his two hands or where the pole intersects where his right ASIS is (front top of hip- the bony protuberance). Now i agree his elbow angle hasn't changed much at all and i see this as correct. What is changing moreso is his shoulder position. If you look fairly quickly through pics 1,2 and 3, you can see how his shoulder is rolling back and over. This is what is lifting the pole. It isn't much movement but then at this stage of the plant there isn't much movement. It is after the pole tips over the fulcrum that the right hand has to accelerate a lot.

So all in all from 4th last to 3rd last the pole is still coming to the horizontal, thus the right hand isn't lifting much, it is mainly guiding the pole to the horizontal. The left hand is also lowering to assist the changing angle or rolling of the pole to the horizontal. From 3rd last to 2nd last the pole comes to the horizontal by the time of 2nd last takeoff. During this stage the right hand simply continues the motion initiated upon leaving the ground from the 4th last step. After the horizontal the right hand moves much more quickly of course.

Continuous lowering of the pole and progressive accelerations in run up and takeoff remain to be sorted out. Precisely what is meant by continuous lowering and progressive acceleration in the pole drop (declination) and the run remains to be explored and clarified.

yes they do but hopefully some of the above words have added to their description.

To finish i would like to look at the definition you provided

The functional objective of the "pole plant action" I define as:

The function of the pole plant is to enable the vaulter to arrive at the takeoff with a body configuration and pole orientation angle placement in the planting box that optimizes the transfer of the final momentum and energy of the approach run into a takeoff that can minimize total system energy loss whilst maximizing the potential and kinetic energy imparted to the vaulter pole system at take - off. Efficiency in directing the vaulter - pole system towards achievement of the ultimate goal namely maximum bar height clearance by the vaulter must also be achieved as a consequence of the plant action used.

Nice, so the plant is merely a function enabling maximum bar clearance and not an end in it self. It achieves this specifically by minimising any total system energy losses during the action of putting the pole in the box. You have the result or goal - the bar clearance, the factors involved - body configuration (position?) and pole orientation, and the objective - minimise energy loss during this action, nice! I would prefer less words but i'm a little like Agapit in this way .

cheers

Pete

hello pvstudent?

Volteur,

I am preparing my responses. As you know from my posts I give considerable care and effort to what I put up. Also I am extremely busy and coaching is my priority at this time.

So there will be a response soon.

By the way what was the problem with the PDF file was page 003 unclear?

Also the discussion I believe at this stage is about clarification of the approach run and plant, not the whole event. Nor is it about coaching methodology. Description and explanation of the approach run and plant needs to be clear before entering the minefield of how to develop and coach this aspect of the vault. I still want to be clear in that we discuss the topic using precise and commonly accepted and understood language otherwise it is in danger of being a futile exercise. The issue about running with the pole is far too important to be left to mere word play or pole vaulting jargon!

I will respond be patient.

PVstudent wrote:Volteur,

I am preparing my responses. As you know from my posts I give considerable care and effort to what I put up. Also I am extremely busy and coaching is my priority at this time.

So there will be a response soon.

By the way what was the problem with the PDF file was page 003 unclear?

Also the discussion I believe at this stage is about clarification of the approach run and plant, not the whole event. Nor is it about coaching methodology. Description and explanation of the approach run and plant needs to be clear before entering the minefield of how to develop and coach this aspect of the vault. I still want to be clear in that we discuss the topic using precise and commonly accepted and understood language otherwise it is in danger of being a futile exercise. The issue about running with the pole is far too important to be left to mere word play or pole vaulting jargon!

I will respond be patient.

thanks pvstudent just thought you might have forgotten. There was no problem with page 3, the problem was i did not know how to get the actual picture up onto the screen in my post. Lacking technical knowledge maybe.

My post was a bit of a mix i agree. I am finding the need though to talk about general matters in order to define some specific boundaries, after all i want to talk from a feeling perspective and you want to talk from a theoretical perspective. How to marry the two is going to be interesting.

I will correct one thing though - The pole begins at vertical - torqueless; and it ends vertical - torqueless, from one end of the runup to landing on the pit.