Mid Mark Chart

[vaultman18]

First, greater force application will increase stride length. This benefit is fairly obvious. If all else is equal, greater force applied to the ground will cause a greater displacement of the athlete’s body. More simply, a greater distance will be covered with each stride.

This says that if all else is "equal". As in leg length and height. What if the force applied is the exact same but one sprinter or vaulter is 6'6" and the other 5'6"?

[SlickVT]

I am not going to get in on this discussion, because I am not nearly as qulified as the people discussing, but I am going to throw my numbers out there.

On my PR vault:

Bar height: 5.28m (17'4")
Hand Grip: 4.67m (15'4")
Takeoff: 4.97m (13'0")
Mid: ??.??m (50'0") <--- ~18" variance from the chart

That is Takeoff: 3.97m (13'0") I think.

All you have to do is to adjust your mid to what the chart says and you clear 18' I guess?

...Oops on the typo... thanks.

If only 5.50m were that easy!

[dj]

hello

All you have to do is to adjust your mid to what the chart says and you clear 18' I guess?

that is indeed "all" you would have to do.. if you could run fast enough, to hold high enough to use that "mid" Six Stride Check Mark.

It’s like debating our own “originâ€

[dj]

hey

before i sign off tonight..11:33 pm here..

i want to say.. i'm still a "SAID" principal person... through and through..

S pecific A daptation to I mposed D emands..

if you want a great run you have to practice it correctly and often.. away from the runway.

good night

flights got changed for Lahti, Finland, leave to morrow.. hopefully..

dj

[KirkB]

PVStudent, here's the same data, reformatted for readability ...

Step Length (metres) at the Rome IAAF World Championships in 1987 and Seoul Olympic Games in 1988.

Code: Select all

                4th   3rd   2nd   Last 4th-3rd 3rd-2nd 2nd-1st
Name     Year  Step  Step  Step   Step   Steps   Steps   Steps
                  
Bubka    1987  2.25  2.09  2.16   1.94   -0.16   +0.07   -0.32
         1988  2.26  2.07  2.11   1.95   -0.19   +0.04   -0.16
                        
Vigneron 1987   N/A  2.12  2.19   2.00     N/A   +0.07   -0.19
         1988  2.10  2.01  2.00   2.05   -0.09   -0.01   +0.05
                        
Gataulin 1987  2.04  2.16  1.87   2.03   +0.07   -0.29   +0.16
         1988  2.02  2.03  1.80   1.94   +0.01   -0.23   +0.14
                        
Bell     1987  2.10  2.06  2.13   2.03   -0.04   +0.07   -0.10
         1988  2.27  2.05  2.27   2.10   -0.22   +0.22   -0.17
                        
Collett  1987   N/A   N/A   N/A    N/A     N/A     N/A     N/A
         1988  1.92  1.96  2.01   1.93   +0.04   +0.05   -0.08

Step Frequency (s/s) at the Rome IAAF World Championships in 1987 and Seoul Olympic Games in 1988.

Code: Select all

               4th   3rd  2nd  Last 4th-3rd 3rd-2nd 2nd-1st
Name     Year Step  Step Step  Step   Steps   Steps   Steps
                  
Bubka    1987  4.5   4.8  4.9   5.1  +0.4     +0.1     +0.2
         1988  4.3   5.4  4.8   5.1  +1.1     -0.6     +0.3
                        
Vigneron 1987  N/A   4.6  4.3   4.9   N/A     -0.3     +0.6
         1988  4.4   4.5  4.7   4.3  +0.1     +0.2     -0.4
                        
Gataulin 1987  4.6   4.9  5.1   4.9  +0.3     +0.2     -0.2
         1988  4.4   5.0  5.4   5.3  +0.1     +0.4     -0.1
                        
Bell     1987  4.3   4.3  4.5   5.3   0.0     +0.2     +0.8
         1988  4.0   4.7  4.2   4.5  +0.7     -0.5     -0.1
                        
Collett  1987  N/A   N/A  N/A   N/A   N/A      N/A      N/A
         1988  4.9   5.1  4.7   5.4  +0.2     -0.4     +0.7

Cautions on interpreting this data (someone might have already covered these) ...

Missing data: It's safe to assume that the subject's height did not change, but what about their grip and mass? (from one

year to the next, I mean!)

Best sample: Does each row represent the best vault for the subject during each event i.e. The highest height cleared? And

what height is that? (not absolutely necessary here, but would be interesting to know)

Accuracy: It is assumed that this data came from digitizing videos. But without reference markers on the subjects, this

process can be manually intensive and thus error prone, so are the values significantly accurate and significantly different

from one step to the other (and from one subject to the other) to rely on?

Given the sample sizes, the values are inherently less accurate than for stride length and frequency of 100m sprinters. i.e.

47 steps ÷ 100m or 47 steps ÷ 10 seconds gives a very precise value, whereas digitizing a single sample per subject per

event does not.

There are surprising variants from step-to-step, and from event-to-event for the same subject. (Variants from subject to

subject should not be surprising.) No one seems very consistent.

• No one consistently increases their frequency in the last 3 steps - except Bubka.
• No one consistently decreases their stride length - not even Bubka.

So what does all this mean? I have no idea!

Kirk

[PVstudent]

Kirkb thank you for reformatting the charts and putting them in the way you have. I am a bit rushed and cannot reply fully to the points raised re consitency across comps, missing data etc at this precise moment have a full coaching day today. (On lunch break!).

Your comments reinforce the point that each individual has to make appropriate adjustments to the proportional relationships of SL and SR during the final 4 steps. Reports only gave the data for these last 4 steps.

What I wanted the readers to be able to see in the way the tables were originally formatted but I couldn't get up properly in my post was for the reader to see for each of the four steps how each vaulter made the average speed of each step according to the step by step SR x SL relationship.

The report for 1987 in Rome was more comprehensive re grips and body mass data. The vaulter's height data was also given. I placed these known and reported values in the 1987 Table that I tried to put up.

Kirkb could I impose on your computer wizardry skills and goodwill and ask if you could please put the data up for me to show the SL and SR for each step as I wanted in the original table.

I will specifically address your concerns later when I can find the time to make a response.

Till then I hope you have read DJ's excellent post re Tim Mack and the the relationships of step length and step rate adjustment. Good practical stuff! ( In principle the methodology of the practice of the use of the chart as expounded is very clear).

I think the discussion using real data is being very helpful especially to me.
Thank your Kirkb for your input.

[PVstudent]

This post simply forces a wider display to allow the table formating in the above post by KirkB to fit without needing to wrap each line.

- master

[KirkB]

Master, it's not just a wider display, it's a monofont. Each character has the same width. You can do this yourself by just highlighting the section of your text that you want to align, then click on the Code button above the Edit box (the box that you type your Reply in).

PVStudent, I know you wanted Grip, Ht, and Mass on the same row as the 4-step data. However, there is a limitation in this forum's software of the number of characters that can be displayed per row on a table (even tho it looks like there's plenty of room, there's not. The first 2 tables that I posted on your behalf hit that limit. There's no room left.

So I've put Grip, Ht, and Mass in the table below.

Code: Select all

         Grip Height  Mass
Name      (m)    (m)  (kg)

Bubka    5.17   1.84    77
Vigneron 5.00   1.81    73
Gataulin 5.10   1.90    77
Bell     4.95   1.93    82
Collett   N/A   1.84    77

Beware of Preview mode too. You need to do that, to ensure that you're CLOSE to the alignment that you want. However, you might not discover the pesky wrapping problem until you Submit. Then, you might need to Edit for your final alignment touch-ups.

It's kind of like finishing your vault. Your run, plant, takeoff, swing, and extension will get you most of the way over the bar. But if you don't move your arms out of the way of the bar, you're SOL.

Oh, did I forget to mention the rockback? No I didn't!!! There is no rockback!

Kirk

[master]

Master, it's not just a wider display, it's a monofont. Each character has the same width. You can do this yourself by just highlighting the section of your text that you want to align, then click on the Code button above the Edit box (the box that you type your Reply in).
Kirk

Kirk, you are correct about using the mono-type font and then posting using the [code] tags. I touched up PVstudent's first post for him using that technique. However, even after doing that, the default width of the PVP pages was not wide enough to display each line without a wrap. Maybe I'm wrong, but I thought your post of the data had that same problem. That is why I posted what I did to widen this "page" of posts also.

- master

[KirkB]

OK, master, I see what you did now. You put in an empty Img box.

That's a good idea - I never thought of that.

And initially, my table was wrapped, so I did Edit, just as I described (the final touch-up). That's probably when you saw it.

So now, the Grip, Ht, and Mass might fit on the same line afterall!

You might want to try that. I'm hitting the sack.

If you use both the empty Img and the Code tricks (all in the same reply), then Bob's your uncle!

Kirk

[agapit]

hello

All you have to do is to adjust your mid to what the chart says and you clear 18' I guess?

that is indeed "all" you would have to do.. if you could run fast enough, to hold high enough to use that "mid" Six Stride Check Mark.

So if one could just get to 60' mid., one would somehow clear 21'. Well, I think few sprinter can be taught to have a mid at 60' while running with the pole.

[powerplant42]

If they have the same speed, their step length is not necessarily the same, but it will be very close depending on their relative height/leg length... very close... unless one of their turnover rates is disgustingly high or extremely low. This is of course assuming that they are running with the same degree of mechanics and form. I'm beginning to get sick of all this arguing over a system that has been proven to work time and time again... If you want to have a good basis of how/where to place a vaulter's checkmark, use the system that dj has outlined for the past dozens of posts. Geez... All this system is is a way to see if a vaulter is hitting the mark that they should be in order to have the right speed (with good running form of course) to jump as high as they can with their given grip, and it also prevents/helps fix over and understriding. That is my ultimate conclusion, and if you don't believe that the chart is a good tool, then simply put, don't use it... but it's there if you want to see how well a vaulter is doing down the runway for their respective grip height. I don't believe that there are any exceptional cases due to the nature of how the chart was constructed: SCIENCE. And it's been shown to fix vaulters' runs! Is general relativity easy to explain to the public? NO! Is it the truth? Has it been shown to be so on many occasions? YES, YES, YES!!! However, I still must hold to my belief that height has a small influence on midmark, although small, and not in the way that many are perceiving it to have... ideal take-off mark. It's closer to the box if the vaulter is taller, so wouldn't that mean that the midmark would need to be adjusted slightly inward, even if it is only a few inches?