Mid Mark Chart

[ladyvolspvcoach]

As I mentioned earlier, when I was first introduced to the mid mark chart I was not convenced that athletes of different body structures and strength levels would ever have the same mid especially if they were significantly different heights. Then I began to use the data in the charts to lay out various rundrills for my athletes in the fall, which we use all through the fall. Then I did a little experiment with Dartfish and found that INDEED when athletes held the same grip their mids were exactly the same regardless of their height. Or at least that's the conclusion that I came to others will certainly come to a different conclusion. But I am reposting a video that shows two lady vaulters running from a (I believe) 6 left approach each holding the same grip. One is 5'6 and the other is 5'1. Each starts from a slightly different spot (probably a result of different accelaration patterns in stride length) but as they each hit their mid marks their strides are exactly the same. I timed them in Dartfish to the .001 seconds. Look carefully at the vaulters before they start the run. Check out what each is wearing because at the take-off you cannot tell. I would reall be interested in all of you observations...
(Link to the video)

[dj]

hey

can't be on line long enough to read and study the post...

is this two different vaults??

the "Six Step Check Mark" (the athletes called it a "MID" and it has always been a Six Step Coaches Mark" for me) should be based on the GRIP... that should put it very close to where it should be.. 8" plus or minus, then the coach can "fine tune" if neccessary.

dj

[ladyvolspvcoach]

pvstudent, what is the grip for each of your examples. Doesn't seem to be on the data presented..

[agapit]

Then I did a little experiment with Dartfish and found that INDEED when athletes held the same grip their mids were exactly the same regardless of their height.

I am sorry. I am not trying to be difficult, but I have never seen anything like this. Is this a coincidence or is there a law of physics or mechanics or chemistry or something else involved. Coach can you please explain here why people holding the same grip regardless of their physical ability and constitution would have a same mid (+/- 8")? Even if they run with the same speed they could have different step length. You do not deny this, right? You are not saying that two people who have the same speed must run with the same step length, right? If you are not saying this than what are you saying?

[PVstudent]

ladyvolspvcoach the pole lengths used were 4.20m for the female and 5.20m for the male.

I have deliberately withheld the actual grip lengths along the pole and with give them when some other responses have been received.

I have looked at the Dartfish video and am surprised on initial review but I will study it more carefully and give a considered response. How do you explain the coincidence of the step marks matching?

When using Dartfish how did you solve the problem of matching the two vauters up at the start of the run? Did you match the two young women up on their mids or the takeoff point? How you established the alignment of the two figures is important. I believe the toe off frame at takeoff is the best alignment point for this matching. When it is done this way, on play back beginning from just prior to commencement of their approach runs do the "mid" mark then match?

[decanuck]

Then I did a little experiment with Dartfish and found that INDEED when athletes held the same grip their mids were exactly the same regardless of their height. Or at least that's the conclusion that I came to others will certainly come to a different conclusion. But I am reposting a video that shows two lady vaulters running from a (I believe) 6 left approach each holding the same grip. One is 5'6 and the other is 5'1. Each starts from a slightly different spot (probably a result of different accelaration patterns in stride length) but as they each hit their mid marks their strides are exactly the same.

Thank you for posting that--it's a great starting point for discussion--but I don't believe this piece of evidence supports the conclusion that 6-step check marks should be the same for a given grip height.

It's just as probable that the fact a taller and a shorter vaulter have the same check could could mean:
- the shorter vaulter is reaching/overstriding
- the taller vaulter is understriding/chopping steps/not getting her knees up
- both of the above



Another thing that doesn't add up about this chart is why it should apply to approaches of different lengths, and poles of different stiffnesses. Say you grip can a certain height on a 12-stride approach that is the highest you can grip with a pole rated at your bodyweight. Now, say you move back to 16 strides and move to a much stiffer pole at the same grip. Your takeoff spot stays the same for both jumps, but on the longer approach you will be moving faster and taking longer strides by the time you're 6 steps from the box. This means, assuming you keep accelerating or at least carry your speed, you'll cover more ground in the last 6 steps, meaning your 6-stride check mark (mid) will need to be further out on the longer run.

I know someone will respond to this by saying that grip height is a product of speed at takeoff and that pole stiffness is a product of swing/inversion/extension effectiveness and never the two shall meet. I say bologna...the two factors overlap a great deal. Where does pole stiffness factor into the chart? Wouldn't using a soft pole on slow approach put you inside the prescribed mid? And a stiff pole outside?

[PVstudent]

decanuck I agree re the interesting Dartfish video example does not prove the point.

I believe the rest of your comments are spot on!

[ladyvolspvcoach]

It's just as probable that the fact a taller and a shorter vaulter have the same check could could mean:
- the shorter vaulter is reaching/overstriding
- the taller vaulter is understriding/chopping steps/not getting her knees up
- both of the above

Actually, neither of these can be true. I coach that an overstride is the extension of the heel beyong the knee and if you look neither of these ladies is guilty of that behavior. Over and understrides are looked at daily. I video the pole runs until neither of these behaviors if active....

also my intent was to provide visual and tangable results that could be discussed not judged. This was not intended to prove any point but to present a sense of reality to the application of the data in the chart. I guess we all just believe what we want to believe..

[ladyvolspvcoach]

It's just as probable that the fact a taller and a shorter vaulter have the same check could could mean:
- the shorter vaulter is reaching/overstriding
- the taller vaulter is understriding/chopping steps/not getting her knees up
- both of the above

Actually, neither of these can be true. I coach that an overstride is the extension of the heel beyong the knee and if you look neither of these ladies is guilty of that behavior. Over and understrides are looked at daily. I video the pole runs until neither of these behaviors if active....

also my intent was to provide visual and tangable results that could be discussed not judged. This was not intended to prove any point but to present a sense of reality to the application of the data in the chart. I guess we all just believe what we want to believe..

[ladyvolspvcoach]

Roman, When I first began to evaluate the data in the chart I was an absolute non believer and told DJ so. But he continued to challeng me on the issue so I decided that my higher sense of rationalization just might have a ding in it (humble that I was) I decided to prove him wrong. Laws of nature and natural order aside, try as I may, I couldn't prove him wrong on the track. The data continued to show me wrong and that it worked in every case regardless of skill level or sex of the athlete. Again I'm just trying to share experiences not be the brightest bulb in the box!!! This is the reality of the experience that i've had. I've just shown you one example there have been many and it always turns out this way...Actually, you can check with JFT. We held a camp last year and using the data had 17 kids run back from their mids to get a 7 left approach. In every case we established their approach on the first attempt ..it was awesome!!!

[ladyvolspvcoach]

Your takeoff spot stays the same for both jumps, but on the longer approach you will be moving faster and taking longer strides by the time you're 6 steps from the box.

decanuck, This is a possible point of contention, but I coach that you accelerate to the mid then attempt to get your feet down as fast as you can from the mid to the take off with a specific focus on the penultimate and take off. You cannot execute these last two steps effectively if you are attempting to accelerate into the take off. So no, the length of the run does not change the mid mark. Finding your longer run should be done by determining your mid and running back from that point for what ever length of approach you are using. Then accelerate into the mid and then attempt to get the feet DOWN as fast as possible and incorporating the penultimate and take off proberly....at least that's what I do....it's pretty darn effective....

[ladyvolspvcoach]

pvstudent, in this particular comparison the two were sync'd at the take-off. I have synced them up at the mid and at the penultimate to study the various differences in the approaches. In this particular case they both have the same flaws in the penultimate so the match up at any sync point...