Kirkb, the follow up as promised.
The 1987 data was accurate and as per the report.
The Seoul study did not report the grips lengths, pole lengths, ratings or flex numbers.
For the the digitizing process a team of specialist biomechanists in both the Rome and Seoul studies performed the data reduction. Also where panning cameras were used specially devised algorithms were devised and used to handle distance and parallex error problems.
The Seoul study used film rates of 200 frames per second and the Rome study 150 frames per second.
Seoul Data for subjects and Height of Jump In the Analysis:
Bubka Height 184cms Mass 83kg 5.90mBest jump
Gataulin Height 190 cms Mass 81kg 5.85m ditto
Vigneron Height 181 cms Mass 75kg 5.70m ditto
Bell Height 193 cms Mass 77kg 5.70m ditto
Collett height 186 cms Mass 74kg 5.70m ditto
Note all the jumpers in the finals had their best performances subjected to the same analysis process. Both reports only published the data in table form for the top finishers in the tables in the body of the reports. In accompanying appendices summary data for other vaulters were provided.
(hope data above come out clearly)
Both reports have as a recognised limitation that the necessay (ideal) anthropometric measures of the individuals were not made and they had to rely on "an optimal anthropometrical "model athlete" based on body height and mass of each individual vaulter.
The tables you rightly pointed out show considerable indidual differences and from the Rome occasion to the Seoul measurements about 1 year later.
I summarize them in this way 'If the data in each individual case is carefully examined and compared (Rome v Seoul) they are rather like personal signatures highly individualist and recognisable despite minor differences from one occassion to the next.' Like signatures when the conditions and the pressures under which they are made are changed they can be expected to vary because the time, context (physical and psychological) and place are different.
However the table in the final corrected format I hope makes very clear that in real life average speed horizontally is a function of stride length x stride rate it is a verifiable factual realtionship. It also can be accomplised by the individual in different proportional contributions from each of step length and step rate. The outcome average speed, it can be concluded from the data provided, can be arrived at in different ways. An average speed is a function of the step length and rate and the same average speed can be arrived at in different ways by athletes of different anthropometric characteristics. My conclusion is that neither stride length nor step rate are in invariant proportional relationship. This applies to intra and inter comparisons of vaulters in the final 4 steps of the pole vault approach run.
There is no surprise in this, if we accept that the data were gathered, treated, processed and published using valid and verifiable methods.
The repeated measures data establish that in real life conditions variability rather than invariance is demonstrated in the final 4 steps of the final approach run of Male World Elite Pole Vaulters in 1987 and 1988.
This conclusion tells us nothing in regard to whether the outcome measured is what the vaulter actually intended or if the patterns are correct or incorrect according to someone's predetermined model of correctness.
Mid Mark Chart
The mid mark chart
Every new opinion at its starting, is precisely a minority of one!
The mid mark chart
VT,
I have not stated that I believe that taller athletes on average apply more ground force. The issue of the application of force to the ground and the shortening of ground contact time and the way in which it influences stride length I have not dealth with specifically as yet.
You come to the "kernel" of the issue when you say "... what we are trying to determine is whether two people who both run technically "perfect" with equal ground force would achieve the same step length?" I think you have to add perfectly identical persons to your caveat here. Also technically perfect for what purpose, for whom and under what circumstances must also to be considered. Do you or I know what technically perfect is? I don't know what the infallible criteria are that determine perfection in the approach run in pole vault!
6'4 male v 5'9 male but with an average speed of 10 m/sec. Since we are dealing in average parameters; here are some possible combinations:
Tall person slightly shorter step length than shorter person but at higher step frequency and same average speed.
Tall person same step length and same step frequency as the short person and same average speed.
Tall person slightly longer step length and lower step frequency than shorter person for same average speed.
Which is actually applied in the individual case will depend on what their optimal is in order to achieve the goal of the task.
The goal of the approach run task is to place the pole in the planting box with the necessary accuracy spatially and temporally to minimize energy / momentum transfer losses in the takeoff and thus create optimal conditions for the subsequent actions of the pole support phases to achieve successful bar clearance within the bounds of safety requirements for that bar height and the level of expertise of the individual.
Carolina21,
I agree the point 0.05 level of significance are low odds (1/20 of the resulting correlation being due to chance).
Body Mass has a higher correlation to stride length than body stature(height)? No surprises there for me since the sprinter's task is to propel their body mass in the direction horizontally towards the finish, within the rules re lanes etc., and since the only opportunity a sprinter has to apply force to that mass is during the alternating ground contacts and F = mass x acceleration the force applied will have a strong relationship to the mass to be moved. The acceleration magnitudes and their directions are the critical considerations in maximising the average speed in sprinting on the flat and are also fundamental to successful pole carriage and placement at speed into the planting box.
Examination of how the pole vaulter actually makes this force application in the alternating ground contacts is a critical issue particularly with respect to models of "sprinting technical correctness" and there being a single fixed or invariant way to be correct in sprinting. In sprinting the person with the highest average speed over the distance wins. This is not necessarily the case in pole vaulting! Speed is a necessary but not sufficient factor in and of itself in the determination of the height of the bar that can be negotiated.
Powerplant42,
I Agree with you re the use of the chart and have no issue with the abundant anecdotal evidence as to its efficacy in practice. I think that once the science on which the chart is claimed to be based is clearly explained there will be even stronger support. The data I supply are there to be discussed in the process of clarifying what the science is of the relationships that underly the chart. To do this successfully I am trying to ensure we are communicating clearly and using data correctly and consistently with the ultimate aim to avoid the rancour of misunderstanding. DJ has also found it frustrating in getting the "science" base across. I sympathize with him in this regard and hopefully when we discuss the facts of the matter in the same way we will all be clearer and even more confident as to validity of the science and efficacy claims made.
DJ,
You were quite right I did misinterpret your statement re Quinon. I simply add to my previous comment that his larger average speed could also have been influenced by a slghtly greater stride rate as well as being due to the slightly longer stride length. Do you agree this possibility has to be considered without any hard data being put up?
Here are the reported data for Ben Johnson and Carl Lewis from the final of the 100m at the 1987 World Championship in Rome. These are taken directly from the scientific report.
Ben Johnson time 9.83secnds and placed first.
Height 1.78 m
Mass 77kg
Number of steps 46.2 steps
Average step frequency 4.6999. steps / sec
Average step length 2.164 m
Ratio average step length / height is 1.216
Carl Lewis time 9.93 secs and placed second.
Height 1.88 m
Mass 80 kg.
Number of steps 44.6 steps
Average step frequency 4.491 steps / sec
Average step length 2.242 m
Ratio average step length / height is 1.193
For a video of this of the race see www.sprintic.com (not particularly good quality video).
The comment I wish to make on the above data is that although the average step length and step rate are correct as calculated it does not follow that any actual single step length value or actual single step rate value of the 46.2 and 44.6 total number of steps demonstrated by Johnson and Lewis respectively, matched exactly the averages as shown in the data above. It must be remembered that actual individual step length and step rate values can and do change during different sections of the race! The same point applies in the approach run in pole vault and is demonstrated in data previously posted by me.
Zhanna Pintusevich-Blok of Ukraine (time of 10.82 sec) upsets heavy favourite Marion Jones of the U.S. (time of 10.85 sec) in the 100 metres, snapping Jones' string of 42 consecutive victories in the Edmonton 2001 Women's World Championship Final of the 100 metres. An excellent example of a very good shorter stature sprinter beating a very good taller one!
Zhanna Pintusevich - Blok: Height 1.64m Mass 62 kg.
Marion Jones: Height 1.78 m Mass 68kg
Data from another of the Pintusevich - Blok and Jones contests (Athens: IAAF World Championship Final 1997) are shown below and illustrate the point made above for Johnson and Lewis.
Step Frequency (steps / sec)
Interval 0 to 30m, 30 to 60m, 60 to 100m, 0 to 100m
Jones 4.05, 4.68, 4.44, 4.38,
Blok 4.47, 4.68, 4.63, 4.59,
Step Length (m)
Interval 0 to 30m, 30 to 60m, 60 to 100m, 0 to 100m,
Jones 2.00, 2.07, 2.23, 2.11,
Blok 1.76, 2.07, 2.19, 2.01,
Jones was placed first on this occasion with a time of 10.83 seconds with Pintusevich - Blok second with a time of 10 .85 seconds. (Reaction time at start for Jones 0.160 sec and Blok 0.130 sec).
Finally Mc Ginnis in his 2000 Report of Men's Pole Vault Approach Run Velocities. 2000 U.S. Trial, Sacramento, California, July 16 2000 having found by linear regression analysis a strong linear relationship between average speed over the interval 10m out to 5m out, measured by videotape analysis, cautions and I quote from page 2 of the report :
" So a vaulter must be fast in order to vault high, but just because he is fast does not guarantee he will vault high."
He provides the following equation for male vaulters to estimate the potential bar height clearance that may be possible for an average approach run velocity (m/sec) between the 10 and 5metre marks.
H = 0.847 + 0.542V
Where:
H = estimated crossbar height in metres
V = approach velocity between 10 and 5 metre marks in m/s.
DJ I hope that this has clearly identified that the Mcginnis study backs up the claim of there being a strong positive linear relationship between average velocity between 10m to 5m out and the potentially achievable bar height. I also draw your attention to the rider that McGinnis placed on this relationship as not being sufficient, in and of itself, to guarantee achievement of that bar height.
It is my understanding that we are in agreement on this point. Is this so?
Raising the questions I have, has not mythologised your chart or data. In fact I think the opposite is happenning. The process of clarification, slow and painful though it may be, is productive and is moving the discussion in the direction of demystification! Hopefully I am not wrong in this perception.
I have not stated that I believe that taller athletes on average apply more ground force. The issue of the application of force to the ground and the shortening of ground contact time and the way in which it influences stride length I have not dealth with specifically as yet.
You come to the "kernel" of the issue when you say "... what we are trying to determine is whether two people who both run technically "perfect" with equal ground force would achieve the same step length?" I think you have to add perfectly identical persons to your caveat here. Also technically perfect for what purpose, for whom and under what circumstances must also to be considered. Do you or I know what technically perfect is? I don't know what the infallible criteria are that determine perfection in the approach run in pole vault!
6'4 male v 5'9 male but with an average speed of 10 m/sec. Since we are dealing in average parameters; here are some possible combinations:
Tall person slightly shorter step length than shorter person but at higher step frequency and same average speed.
Tall person same step length and same step frequency as the short person and same average speed.
Tall person slightly longer step length and lower step frequency than shorter person for same average speed.
Which is actually applied in the individual case will depend on what their optimal is in order to achieve the goal of the task.
The goal of the approach run task is to place the pole in the planting box with the necessary accuracy spatially and temporally to minimize energy / momentum transfer losses in the takeoff and thus create optimal conditions for the subsequent actions of the pole support phases to achieve successful bar clearance within the bounds of safety requirements for that bar height and the level of expertise of the individual.
Carolina21,
I agree the point 0.05 level of significance are low odds (1/20 of the resulting correlation being due to chance).
Body Mass has a higher correlation to stride length than body stature(height)? No surprises there for me since the sprinter's task is to propel their body mass in the direction horizontally towards the finish, within the rules re lanes etc., and since the only opportunity a sprinter has to apply force to that mass is during the alternating ground contacts and F = mass x acceleration the force applied will have a strong relationship to the mass to be moved. The acceleration magnitudes and their directions are the critical considerations in maximising the average speed in sprinting on the flat and are also fundamental to successful pole carriage and placement at speed into the planting box.
Examination of how the pole vaulter actually makes this force application in the alternating ground contacts is a critical issue particularly with respect to models of "sprinting technical correctness" and there being a single fixed or invariant way to be correct in sprinting. In sprinting the person with the highest average speed over the distance wins. This is not necessarily the case in pole vaulting! Speed is a necessary but not sufficient factor in and of itself in the determination of the height of the bar that can be negotiated.
Powerplant42,
I Agree with you re the use of the chart and have no issue with the abundant anecdotal evidence as to its efficacy in practice. I think that once the science on which the chart is claimed to be based is clearly explained there will be even stronger support. The data I supply are there to be discussed in the process of clarifying what the science is of the relationships that underly the chart. To do this successfully I am trying to ensure we are communicating clearly and using data correctly and consistently with the ultimate aim to avoid the rancour of misunderstanding. DJ has also found it frustrating in getting the "science" base across. I sympathize with him in this regard and hopefully when we discuss the facts of the matter in the same way we will all be clearer and even more confident as to validity of the science and efficacy claims made.
DJ,
You were quite right I did misinterpret your statement re Quinon. I simply add to my previous comment that his larger average speed could also have been influenced by a slghtly greater stride rate as well as being due to the slightly longer stride length. Do you agree this possibility has to be considered without any hard data being put up?
Here are the reported data for Ben Johnson and Carl Lewis from the final of the 100m at the 1987 World Championship in Rome. These are taken directly from the scientific report.
Ben Johnson time 9.83secnds and placed first.
Height 1.78 m
Mass 77kg
Number of steps 46.2 steps
Average step frequency 4.6999. steps / sec
Average step length 2.164 m
Ratio average step length / height is 1.216
Carl Lewis time 9.93 secs and placed second.
Height 1.88 m
Mass 80 kg.
Number of steps 44.6 steps
Average step frequency 4.491 steps / sec
Average step length 2.242 m
Ratio average step length / height is 1.193
For a video of this of the race see www.sprintic.com (not particularly good quality video).
The comment I wish to make on the above data is that although the average step length and step rate are correct as calculated it does not follow that any actual single step length value or actual single step rate value of the 46.2 and 44.6 total number of steps demonstrated by Johnson and Lewis respectively, matched exactly the averages as shown in the data above. It must be remembered that actual individual step length and step rate values can and do change during different sections of the race! The same point applies in the approach run in pole vault and is demonstrated in data previously posted by me.
Zhanna Pintusevich-Blok of Ukraine (time of 10.82 sec) upsets heavy favourite Marion Jones of the U.S. (time of 10.85 sec) in the 100 metres, snapping Jones' string of 42 consecutive victories in the Edmonton 2001 Women's World Championship Final of the 100 metres. An excellent example of a very good shorter stature sprinter beating a very good taller one!
Zhanna Pintusevich - Blok: Height 1.64m Mass 62 kg.
Marion Jones: Height 1.78 m Mass 68kg
Data from another of the Pintusevich - Blok and Jones contests (Athens: IAAF World Championship Final 1997) are shown below and illustrate the point made above for Johnson and Lewis.
Step Frequency (steps / sec)
Interval 0 to 30m, 30 to 60m, 60 to 100m, 0 to 100m
Jones 4.05, 4.68, 4.44, 4.38,
Blok 4.47, 4.68, 4.63, 4.59,
Step Length (m)
Interval 0 to 30m, 30 to 60m, 60 to 100m, 0 to 100m,
Jones 2.00, 2.07, 2.23, 2.11,
Blok 1.76, 2.07, 2.19, 2.01,
Jones was placed first on this occasion with a time of 10.83 seconds with Pintusevich - Blok second with a time of 10 .85 seconds. (Reaction time at start for Jones 0.160 sec and Blok 0.130 sec).
Finally Mc Ginnis in his 2000 Report of Men's Pole Vault Approach Run Velocities. 2000 U.S. Trial, Sacramento, California, July 16 2000 having found by linear regression analysis a strong linear relationship between average speed over the interval 10m out to 5m out, measured by videotape analysis, cautions and I quote from page 2 of the report :
" So a vaulter must be fast in order to vault high, but just because he is fast does not guarantee he will vault high."
He provides the following equation for male vaulters to estimate the potential bar height clearance that may be possible for an average approach run velocity (m/sec) between the 10 and 5metre marks.
H = 0.847 + 0.542V
Where:
H = estimated crossbar height in metres
V = approach velocity between 10 and 5 metre marks in m/s.
DJ I hope that this has clearly identified that the Mcginnis study backs up the claim of there being a strong positive linear relationship between average velocity between 10m to 5m out and the potentially achievable bar height. I also draw your attention to the rider that McGinnis placed on this relationship as not being sufficient, in and of itself, to guarantee achievement of that bar height.
It is my understanding that we are in agreement on this point. Is this so?
Raising the questions I have, has not mythologised your chart or data. In fact I think the opposite is happenning. The process of clarification, slow and painful though it may be, is productive and is moving the discussion in the direction of demystification! Hopefully I am not wrong in this perception.
Every new opinion at its starting, is precisely a minority of one!
-
ladyvolspvcoach
- PV Follower
- Posts: 606
- Joined: Wed Oct 06, 2004 1:52 pm
- Location: Knoxville, Tennessee
- Contact:
mid
Pvstudent
I genuinly apologize for not responding, but I have been dealing with some health problems that have kept me off the forum. I've sent your comments regarding video performances and the video that I published to Dartfish for their response, since if what you say is true then their technology is not reliable for the uses that I have supported it. When they get back to me I'll relay their comments. In the mean time I'll be unavailabel after next Wed.
At least my cranioanalitis isn't so bad that I have forgotten or missed your reply to my post re the use of Dartfish.
So were the facts of the matter wrong? Can you respond or has your own dose of cranioanalitis left you with convenient amnesia!
I genuinly apologize for not responding, but I have been dealing with some health problems that have kept me off the forum. I've sent your comments regarding video performances and the video that I published to Dartfish for their response, since if what you say is true then their technology is not reliable for the uses that I have supported it. When they get back to me I'll relay their comments. In the mean time I'll be unavailabel after next Wed.
The mid mark chart
ladyvolspvcoach,
Thank you for the response. I hope your health issues are satisfactorily resolved.
Just would like you to know there is no malice or ill will toward you personally. I look forward to the Dartfish response. If the question is to resolved I will be as interested as you are in the answers they provide.
Thanks for getting back to me.
Thank you for the response. I hope your health issues are satisfactorily resolved.
Just would like you to know there is no malice or ill will toward you personally. I look forward to the Dartfish response. If the question is to resolved I will be as interested as you are in the answers they provide.
Thanks for getting back to me.
Every new opinion at its starting, is precisely a minority of one!
Good morning
Let’s see if our math will give us some answers…
First Bubka 1987..
Add…. 2.25
………2.09
………2.16
………1.94
=……..8.44..divided by 4 = 2.11m per step times 6 = 12.66 plus 4.40m take off = 17.06 as a possible Six Step Check..??
Next Add….4.5 ss
…………….4.8 ss
…………….4.9 ss
…………….5.1 ss
=………….19.3…..divided by 4 = 4.82ss..
Divide 6 by 4.82ss = 1.2444 seconds to cover six steps..
Divide 12.66m by 1.2444 seconds = 10.17MPS ??
Or have I done some of the math wrong………..
Hopefully this will give us enough info to “shift” the numbers to us other combinations of stride length and stride frequency..
dj
ps… and not to “blast” any data or research, I find the variance in stride lengths over the last four to be generally way out of sync. Of course there should be a variance at the penultimate if it is performed correctly, but I have not found the ‘undulations’ as they were called in the thousands of runs I have monitored, including, and especially Earl Bells, whom I have monitored for over 15 years, very closely, hundreds of jumps and many of those runs were monitored with markers at every step, filmed, from the “Six Stride Check”. Earl did have a weak “side” as almost all runners do and he had one leg shorter than normal.. that he wore and insert for balance. But the numbers reported there for Earl is way out of the norm. I don’t think the data collectors caught the true COM from step to step..
I use film myself but “stop frame” each step when the thighs are as parallel as possible, or the knees on even.. to me that gives a better gauge of step length from support to support.. and the best point where the “mass” is likely to be the same..
Let’s see if our math will give us some answers…
First Bubka 1987..
Add…. 2.25
………2.09
………2.16
………1.94
=……..8.44..divided by 4 = 2.11m per step times 6 = 12.66 plus 4.40m take off = 17.06 as a possible Six Step Check..??
Next Add….4.5 ss
…………….4.8 ss
…………….4.9 ss
…………….5.1 ss
=………….19.3…..divided by 4 = 4.82ss..
Divide 6 by 4.82ss = 1.2444 seconds to cover six steps..
Divide 12.66m by 1.2444 seconds = 10.17MPS ??
Or have I done some of the math wrong………..
Hopefully this will give us enough info to “shift” the numbers to us other combinations of stride length and stride frequency..
dj
ps… and not to “blast” any data or research, I find the variance in stride lengths over the last four to be generally way out of sync. Of course there should be a variance at the penultimate if it is performed correctly, but I have not found the ‘undulations’ as they were called in the thousands of runs I have monitored, including, and especially Earl Bells, whom I have monitored for over 15 years, very closely, hundreds of jumps and many of those runs were monitored with markers at every step, filmed, from the “Six Stride Check”. Earl did have a weak “side” as almost all runners do and he had one leg shorter than normal.. that he wore and insert for balance. But the numbers reported there for Earl is way out of the norm. I don’t think the data collectors caught the true COM from step to step..
I use film myself but “stop frame” each step when the thighs are as parallel as possible, or the knees on even.. to me that gives a better gauge of step length from support to support.. and the best point where the “mass” is likely to be the same..
-
KirkB
- PV Rock Star
- Posts: 3550
- Joined: Mon May 19, 2008 6:05 pm
- Expertise: Former College Vaulter; Former Elite Vaulter; Former Coach; Fan
- Lifetime Best: 5.34
- Favorite Vaulter: Thiago da Silva
- Location: Vancouver, BC, Canada
Re: The mid mark chart
PVstudent wrote:Kirkb, the follow up as promised.
The 1987 data was accurate and as per the report.
The Seoul study did not report the grips lengths, pole lengths, ratings or flex numbers.
For the the digitizing process a team of specialist biomechanists in both the Rome and Seoul studies performed the data reduction. Also where panning cameras were used specially devised algorithms were devised and used to handle distance and parallex error problems.
...
The tables you rightly pointed out show considerable indidual differences and from the Rome occasion to the Seoul measurements about 1 year later.
I summarize them in this way 'If the data in each individual case is carefully examined and compared (Rome v Seoul) they are rather like personal signatures highly individualist and recognisable despite minor differences from one occassion to the next.' Like signatures when the conditions and the pressures under which they are made are changed they can be expected to vary because the time, context (physical and psychological) and place are different.
...
There is no surprise in this, if we accept that the data were gathered, treated, processed and published using valid and verifiable methods.
...
PVStudent, thanks for this information. It tells me that the analysis was conducted in the most professional way possible.
I was actually expecting a lack of accuracy in the gathering of the data to explain away some of the "inconsistencies" in the data.
DJ's post above alludes to this as well.
If I understand you right, I'm thinking that you consider the mathematical product of stride length x frequency as a significant factor - more important than looking at stride length or freq individually. Perhaps if we looked at that - either tabular or in a line graph - we might see the pattern more clearly (and the variances would lessen)?
I really appreciate your scientific approach to this analysis!
And I accept your "signature" explanation - I have no better explanation.
I'd just like to see more samples in the study. Two events isn't usually enough to prove a trend. It's too bad EVERY jump of every vaulter in each of the two events wasn't digitized.
Kirk
Run. Plant. Jump. Stretch. Whip. Extend. Fly. Clear. There is no tuck! THERE IS NO DELAY!
Re: The mid mark chart
PVstudent wrote:Volteur.
The assymmetry you note in the respective step lengths and rates is not galloping (that is if I understand your human galloping rhythm suggestion correctly) but is a function of the pole carry and the trunk involvement in initiating and progressing the plant through to the last step.
There is also evidence that there is some step length assymmetry in the mid phase of the approach run (see female case study data chart and the male case study 5.30m jump).
The differences are small but can also be associated with the pole oscillations and the rate of pole angle change entering on to the final 6 steps of the approach.
A low angle of pole carry and a low bottom hand increase the degree of right and left step length differences in some individual cases. I have also found that an overly wide grip hand separation increases the assymetry.
The differences refered to are small. Assymetry of left v right side step lengths, you are quite right have been observed in other running take-offs. I am very hesitant to call it galloping.
In the context of pole vaulting it has important functional significance in respect to timing and synchronizing of the arms and legs with pole carriage and plant actions.
I base my comments on observations and measurements made from video recording, on practical coaching and making direct measurements on the runway.
Cheers for the info, so i have this from the discussion now
The small asymmetry observed earlier in the run is due to the effect of carrying the pole
The larger degree of asymmetry later in the run is due to carrying the pole AND the greater weight of the pole once it has passed 45 degrees or at the 6th last step AND the mechanics required for any takeoff.
3 factors leading to this asymmetry? Would you agree?
Volteur
The mid mark chart
Volteur,
No I did not say weight of the pole once it has passed 45 degrees! The weight of the pole remains the same throughtout the entire run. The torque exerted by the weight of the pole changes as the angle of the pole to the horizontal changes during the run not the weight. The vaulter may feel the effect of the increasing torque as an increase in pole carrying angle resistance and ascribe it to increased weight which is incorrect.
The issue, in the final 6 steps and particularly the 3rd step out for 3-step plant technique occurs at the inititiation of the plant. Earlier in the run the alignment of the pole across the body (left hand lined up in front of the sternum about 20cms in front of the lower part of the manubrium with the right hand immediately lateral and just posterior to the right hip and gluteal mass for a right handed vaulter) encourages slight assymmetry which can be exacerbated by a very wide grip.
Also contributing is faulty running in which the pelvis is slightly rotated to the right in the horizontal plane. This produces 'crab like' running with the left side of the vaulter (right handed vaulter) always leading slightly in advance rather than with the lower body 'square' on to the run direction.
Do I agree? Yes with caveats above. Pole carriage and movement transition into the plant, rhythmical structure and pole linear and angular acceleration ("pole drop") must be viewed in the individual case to assess the balance, harmony of arms, torso and lower limbs integration and overall postural stabilty in the run.
The grips of the lower and higher hands in association with the degree of elbow flexions and shoulder abductions and wrist postures also may force the vaulter to compensate by running slightly assymetrically. Carrying with "hunched" shoulders due to faulty grips also may contribute to assymetrical run step compensations.
The pole carriage and run is widely touted by experts as being critical to successful pole vault outcome. Finding actual data and scientific study of the full run up approach and plant in pole vault is sadly like looking for hens teeth!
The larger degree of asymmetry later in the run is due to carrying the pole AND the greater weight of the pole once it has passed 45 degrees or at the 6th last step AND the mechanics required for any takeoff.
No I did not say weight of the pole once it has passed 45 degrees! The weight of the pole remains the same throughtout the entire run. The torque exerted by the weight of the pole changes as the angle of the pole to the horizontal changes during the run not the weight. The vaulter may feel the effect of the increasing torque as an increase in pole carrying angle resistance and ascribe it to increased weight which is incorrect.
The issue, in the final 6 steps and particularly the 3rd step out for 3-step plant technique occurs at the inititiation of the plant. Earlier in the run the alignment of the pole across the body (left hand lined up in front of the sternum about 20cms in front of the lower part of the manubrium with the right hand immediately lateral and just posterior to the right hip and gluteal mass for a right handed vaulter) encourages slight assymmetry which can be exacerbated by a very wide grip.
Also contributing is faulty running in which the pelvis is slightly rotated to the right in the horizontal plane. This produces 'crab like' running with the left side of the vaulter (right handed vaulter) always leading slightly in advance rather than with the lower body 'square' on to the run direction.
Do I agree? Yes with caveats above. Pole carriage and movement transition into the plant, rhythmical structure and pole linear and angular acceleration ("pole drop") must be viewed in the individual case to assess the balance, harmony of arms, torso and lower limbs integration and overall postural stabilty in the run.
The grips of the lower and higher hands in association with the degree of elbow flexions and shoulder abductions and wrist postures also may force the vaulter to compensate by running slightly assymetrically. Carrying with "hunched" shoulders due to faulty grips also may contribute to assymetrical run step compensations.
The pole carriage and run is widely touted by experts as being critical to successful pole vault outcome. Finding actual data and scientific study of the full run up approach and plant in pole vault is sadly like looking for hens teeth!
Every new opinion at its starting, is precisely a minority of one!
Re: The mid mark chart
PVstudent wrote:Volteur wrote
The larger degree of asymmetry later in the run is due to carrying the pole AND the greater weight of the pole once it has passed 45 degrees or at the 6th last step AND the mechanics required for any takeoff.
No I did not say weight of the pole once it has passed 45 degrees! The weight of the pole remains the same throughout the entire run. The torque exerted by the weight of the pole changes as the angle of the pole to the horizontal changes during the run not the weight. The vaulter may feel the effect of the increasing torque as an increase in pole carrying angle resistance and ascribe it to increased weight which is incorrect.
i should have called it relative weight then, yes? It radically increases after this 45 degree angle.
The issue, in the final 6 steps and particularly the 3rd step out for 3-step plant technique occurs at the inititiation of the plant. Earlier in the run the alignment of the pole across the body (left hand lined up in front of the sternum about 20cms in front of the lower part of the manubrium with the right hand immediately lateral and just posterior to the right hip and gluteal mass for a right handed vaulter) encourages slight assymmetry which can be exacerbated by a very wide grip.
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.
Also contributing is faulty running in which the pelvis is slightly rotated to the right in the horizontal plane. This produces 'crab like' running with the left side of the vaulter (right handed vaulter) always leading slightly in advance rather than with the lower body 'square' on to the run direction.
Agreed again although this is going to happen to a degree no matter what because of the pole being carried, minimisation of it is essential.
Do I agree? Yes with caveats above. Pole carriage and movement transition into the plant, rhythmical structure and pole linear and angular acceleration ("pole drop") must be viewed in the individual case to assess the balance, harmony of arms, torso and lower limbs integration and overall postural stabilty in the run.
The grips of the lower and higher hands in association with the degree of elbow flexions and shoulder abductions and wrist postures also may force the vaulter to compensate by running slightly asymmetrically. Carrying with "hunched" shoulders due to faulty grips also may contribute to asymmetrical run step compensations.
The pole carriage and run is widely touted by experts as being critical to successful pole vault outcome. Finding actual data and scientific study of the full run up approach and plant in pole vault is sadly like looking for hens teeth!
It is true all of the factors you listed above are the factors involved in attempting to develop a balanced vault - runup, takeoff, pole bend/inversion, pull and push, clearance. It's just that focussing on them is not going to be productive. Although removing hunched shoulders is pretty important, removing all roundedness in the shoulder girdle would be a mistake, as some in necessary for pole carry.
For me balance is the key. If the run remains balanced then the takeoff can be balanced, if balance is lost in the run then the imbalances will be taken into the takeoff. And so on.
A balanced run comes from correct pole carry and from a progressively accelerating runup. It's that simple really i believe. Gaining the ability to progressively accelerate takes time though as does finding a better and better way of carrying the pole.
volteur
good morning
is there a possibility that practicing the approach run on the track with the “Six Stride Check Mark” marked, step for step, over the last six… would possibly accelerate the the vaulters learning curve toward an accurate and more accelerated run?
agapit wrote
and this, I think, actually confirms the “Six Step Chart” rather than condemning it, as does the additional data that has been posted on stride length, stride frequency and meters per second (mps).
14 centimeters is reasonably accurate (even in the long jump) on an approach run.... but “several feet is not”..
and by practicing the run in this way.. there would be a possibility that any “weak” strides could be elinminate.. as Maurice Greene did in the 100 meters by eliminating 2” per step for 47 steps for a grand total of 94”!
and is it possible for some or all of you guys to devise other possibilities within the data parameters we were given or can find from other studies,other than this one example.
i found the meters per second average for 6 steps to be too high.. over 10 MPS rater than the average of 9.8 or even 9.9 MPS.
take care
dj
A balanced run comes from correct pole carry and from a progressively accelerating runup. It's that simple really i believe. Gaining the ability to progressively accelerate takes time though as does finding a better and better way of carrying the pole.
is there a possibility that practicing the approach run on the track with the “Six Stride Check Mark” marked, step for step, over the last six… would possibly accelerate the the vaulters learning curve toward an accurate and more accelerated run?
agapit wrote
Athlete #1. Average Speed 10m/s; with average step cadence of 4.60 steps/second; with 6 step mid-mark at 17.04m and take off point at 4m from the box and average step length of 2m 17cm.
Athlete #2. Average Speed 10m/s; with average step cadence of 4.65 steps/second; with 6 step mid-mark at 16.90m and take off point at 4m from the box and average step length of 2m 15cm.
This will gain difference of 14 centimeters or 5.51 inches on the mid-mark between these two athletes.
and this, I think, actually confirms the “Six Step Chart” rather than condemning it, as does the additional data that has been posted on stride length, stride frequency and meters per second (mps).
14 centimeters is reasonably accurate (even in the long jump) on an approach run.... but “several feet is not”..
and by practicing the run in this way.. there would be a possibility that any “weak” strides could be elinminate.. as Maurice Greene did in the 100 meters by eliminating 2” per step for 47 steps for a grand total of 94”!
and is it possible for some or all of you guys to devise other possibilities within the data parameters we were given or can find from other studies,other than this one example.
i found the meters per second average for 6 steps to be too high.. over 10 MPS rater than the average of 9.8 or even 9.9 MPS.
First Bubka 1987..
Add… 2.25.... stride length
…………2.09
…………2.16
…..……1.94
=……..8.44..total……….divided by 4 = 2.11m per step.... times 6 = 12.66 plus 4.40m for the take off distance = 17.06 as a possible Six Step Check..??
take care
dj
The mid mark chart
Volteur,
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 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.
Dj I will respond to your comments soon but coaching committments call I must go.
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.
Dj I will respond to your comments soon but coaching committments call I must go.
Every new opinion at its starting, is precisely a minority of one!
Re: The mid mark chart
PVStudent
agreed this is a good topic with much to discover within so i will cut and paste your last thread into the ??? takeoff? plant? runup? thread and continue from there
can you suggest where to put it?
cheers
Pete
agreed this is a good topic with much to discover within so i will cut and paste your last thread into the ??? takeoff? plant? runup? thread and continue from there
can you suggest where to put it?
cheers
Pete
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