Take off Angle or Jump Angle

[PVGuy89]

I was experimenting a little bit today with different take off angles from 3 lefts and i've noticed that a pretty low take off angle (20 degrees ish) helped me blow through the pole and helped me set up a better upward push with my hands allow a great leading chest and that a higher (30-45 degrees?) So was wondering what is an ideal Jump angle off the ground as if you didnt have a pole when you jumped off the ground at take off? I've heard many different angles form 20 degrees to 60 degrees.... and how much does the pole length depend on the jump angle.

And I believe that the Jump angle and the take off angle will differ a little bit. no? cause the pole will start bending and start putting up your CM.

Any thoughts? thanks.

[KirkB]

... i've noticed that a pretty low take off angle (20 degrees ish) helped me blow through the pole and helped me set up a better upward push with my hands allow a great leading chest and that a higher (30-45 degrees?) So was wondering what is an ideal Jump angle off the ground ...

Elite athletes have been "scientifically measured" at either 18 or 19 degrees (on average). I forget which, and I forget the name of the biomechanic who wrote the paper that I'm thinking of. I can look that up tomorrow, but not tonight.

Sadly, a very common problem is not jumping UP even 18-19 degrees ... a FLAT takeoff. Not sure why you call 20 degrees "low", but if you're correct in your estimate (this is really hard to estimate), then you're about right. A takeoff of 30-45 degrees is simply too much of a PLANT with the heel of your takeoff foot, leading to braking. I don't think pole length is a factor.

... I believe that the Jump angle and the take off angle will differ a little bit. ...

What's your pole angle? With a little bit of trig, you can compute it if you know your takeoff distance from the stopboard, and your grip (don't forget to allow 8" of box depth). If I'm right about pole length not being a factor, then any similarity (or difference) in pole angle and takeoff angle is purely coincidental.

... cause the pole will start bending and start putting up your CM. ...

No ... this is incorrect ... becuz the angle of the pole and the angle of the takeoff are measured BEFORE the pole starts to bend. Therefore, the pole bend has no effect on the angle.

Kirk

[dj]

Take off angle:

The definition of take off angle from the Biomechanical studies is this….

Take off angle: The angle between the direction of the vaulter’s motion and the runway. It also shows how the horizontal and vertical velocities are related. Vertical velocity increases as takeoff angle increases.

Quate…
becuz the angle of the pole and the angle of the takeoff are measured BEFORE the pole starts to bend. Therefore, the pole bend has no effect on the angle.

This is actually incorrect….

The amount of pole bend, the impulse at the takeoff and the stiffness of the pole are all huge factors in determining this angle…

If you track the top grip to max bend, distance from Take off and height from reach you have the “triangle” to determine this angle…

The amount of pole bend is big… for example Tully (look in the numbers thread) was "under" by 8 inches.. had a very poor vertical impulse.. 1.64 vertical velocity!! A 11.6 degree TO angle and 33.2% bend…

Same pole.. 2 inches under… had a 2.62 vertical velocity… a 18.9 degree TO angle with only 27.4% max bend..

Now tully had another jump.. a little stiffer pole.. 10 inches under.. BUT managed to “jump” push off faster even though he was under… had a 2.38 vertical velocity because of the stiff pole and the “jump”… TO angle was 17.0% and pole bend was 28.0%...

T-mack at the 2004 trials had 3 jumps at 6.04.. one good one with the same pole as the 5.90 jump.. and the last one with a different 5.20 pole.. we went through the numbers of the two jumps.. everything was identical except his TO angle was much higher on the 5.20, stiffer pole.. those watching the jump and numbers with me went “WOW” he had a great TO angle!! Why didn’t he finish the jump!! What they didn’t understand was the angle was created by the stiffer pole… since the pole was stiffer he had a longer “max bend length to rotate to vertical.. and even thought the takeoff speed, technique, etc was the same he could not create more “energy” with his body swing to get the longer pole cord to vertical….

I have said this several times before….. the “impulse” (all other things; speed, plant/TO technique.. being equal) is what is an ABSOLUTE.. the takeoff must be “free-er, reach as high as humanly possible (with both hands.. AGRESSIVE, before the pole tip hits the back of the box.

Bubka had 16 to 18 degree Take off's.. with amount of pole bend having a direct correlation...

greater pole bend flatter TO angle..

one of the things this taught me was the amount of pole bend didn't allways mean the pole was to small... Tully proved that at the 84 trials when he changed to a larger pole but had to change back to a small pole when he relized the takeoff is what over bent the smaller pole not that it's flex was to small.. he set the Trial record on what was considered a 'small" pole... go figure

dj

[PVGuy89]

So let me clarify if i understand what ur saying. So the pole does make difference of the take off angle because the pole which wants to unbend to being straight is giving you a vertical velocity. and this happens right after take off or no? also I've analyzed and compared many vaults like lavillenie. His take off angle seems to be very small or hardly existent no? and also he crushes his poles and the unbending upwards very fast because he puts all his energy horizontally (most of it) to gather all that energy to throw him upwards. and also does the pole bending % significant of how effective the jump/vault is? what is an ideal pole bending percent. From what seen from you numbers looks like around 30%.

Also another vault that is astoundingly different or basically opposite from lavillenie and alot others is Ashton Eaton Vault.. he has a very free take off and barely bends the pole because he jump SOOO HIGH UP!

Here's a link to his vault: http://www.flotrack.org/videos/coverage/view_video/236615-2010-mpsf-indoor-track-field-championships/309821-ashton-eaton-526m-pole-vault-pr

I dont know the numbers for his vault but he's quite fast and cant JUMP! here are his stats:

http://www.athletic.net/TrackAndField/Athlete.aspx?AID=675996

And also i was wondering if tully's vertical velocity was at TO or while the pole was unbending? because at take off i believe that the vertical velocity can't be that high right?

and thanks for responding this is very helpful!!

[KirkB]

… becuz the angle of the pole and the angle of the takeoff are measured BEFORE the pole starts to bend. Therefore, the pole bend has no effect on the angle.

This is actually incorrect….

The amount of pole bend, the impulse at the takeoff and the stiffness of the pole are all huge factors in determining this angle…

I agree that the impulse is extremely important. We may be talking about 2 different things. Do you not agree that the angle of the pole is measured BEFORE the pole starts to bend? This would be IN ADDITION TO your points about the impulse, and the angle of the chord of the pole DURING its bend.

To use another example, Rick Baggett in his Ground Work vid talks about raising the ANGLE of the pole on takeoff by reaching as high as you can on your plant ... and then some. Is THAT not what's called the "pole angle"? The idea is that your want to create the biggest angle that you can. Shorter vaulters ... smaller angles. Lower grips ... bigger angles.

Kirk

[dj]

Hey

We are beginning to put items, pole angle at the plant and vertical velocity after maximum pole bend that don’t factor in on the Take off Angle.. number… they are effected or do effect the result but the scientific data is separated by:

Approach Run (last two steps before the pole striking the back of the box)
Plant (the instant the pole strikes the back of the box),
Take Off (the instant when the takeoff foot leaves the ground)
Swing (from takeoff until the distance from the CG to the box is minimum)
Rockback (from end of swing until hips are above lower hand)
Extension, Pull and Turn(from end of Rockback until top hand release)….
Upper Hand Release (the instant when the upper hand releases its grip from the pole
Flight and Clearence (max COM, Time CG max height, penetration at max COM,

We are talking about the Take Off angle her…

There is a Pole Angle at the Plant, for example on Tully’s 10 inches under vault it was 29.2 degrees.. There is also a pole angle given at the Takeoff.. of 30.4 degrees.. the difference in these numbers and the “math” is how Takeoff Angle is determined.. in this jump it was 17.0 degrees..

That Angle, the Takeoff Angle, not the Plant (pole) Angle is determined by the vaulters top hand “track” AFTER pole support. This is where you MUST consider the pole size, takeoff position, AND the impulse.

I really don’t want to start an argument here, please, but this is what has and continues to be miss interpreted by 99% of the vault community. The way it has been looked at for at least the last 15 plus years is that the ‘greater” this angle the better vaulter you are or the better you should vault. This is a total miss conception according to the physics of the event.

Apparently Lavillenie is being criticized for a flat takeoff.

This is why calling t-mack a “pole squashier” and that he would have to “jump” big at the plant to increase the Takeoff Angle or never reach world class. These “thoughts” totally missed the physics. What we really have missed here is that his “numbers” were so much better “with physics’ than 99.9% of all vaulters that if a vaulter was faster, took off slightly more “out” and used his “physics” they would jump a world record…

Alan is correct if “pre-jump” means Impulse… Alan is definitely right about a free takeoff.. the greater the Impulse just before the pole tip smacks the back of the box the higher you should grip… the higher you can grip (with the correct swing technique, the correct grip, and the correct bend) the higher you jump….

Correct me if I’m wrong but the majority “concept” for the vault right now, world wide, today, is that a greater Takeoff Angle is a MUST!... less bend in the pole is desirable and a pole that will react hard and fast and that will “throw” you very high is KING!!!

Those are all misconceptions and work against the physics of the event..

In the long jump you can determine the Takeoff Angle by speed and impulse… you can’t use long jump “science” to determine good or bad angles in the pole vault.

Yes, speed is important, yes “impulse” is huge.. just like in the long jump.. impulse meaning “a greater force” in a shorter time.. the “impulse” in the vault must be at/before pole support and as strong as possible without slowing down…

The resultant velocity is what is “key”.. and that is determined by not only the horizontal and vertical velocity (even though the “math” is from those numbers.) But the Impulse, the flex of the pole, the timing of the Impulse, the position of the body at the impulse/plant. Etc..

The amount of pole bend or a “flat” takeoff is not THE issue, like we are seemly making it out to be.. you can have a “flat” TO like t-mack had, 11 degrees ??ish, but have the correct impulse that has the mass is moving “UP” AND forward very fast, .49 seconds to max bend.. You can have a 30/33% bend like Mack or apparently Lavillenie. with no “ill” effects only huge air, not because the pole “threw” him but because he swung very fast and got the body mass moving “UP” (impulse), accelerating up, and “lessening the load” allowing the pole to “unload” or straighten with the moving body… creating the illusion that the pole “throws” the vaulter.

To try and answer your questions.. there is no “optimum” Takeoff Angle for everyone.. even from jump to jump… the Takeoff Angle is a “result” not a target.. the target should be in the numbers produced in the Bubka vault that I posted in another thread and the numbers (matching them proportionately with more speed at takeoff and possibly a sooner impulse, before the pole hits the back of the box ) T-Mack had on his 2004 trials 5.90 jump, which I don’t have at this time or I would post them..

Obviously the numbers in Lavillenie jumps (which I don’t have) are “almost” on.. because of positive results… and to look at the jumps and say he is “too flat”.. too anything without knowing the numbers.. and trying to determine what really should change, impulse, pole size, position at takeoff.. swing speed. etc would not really help us move the vault forward…

My hope is we can come to terms with these concepts. Right now the lack of understanding of this issue is determining our coaching methods, the pole sizes we use and even the design/engineering we are using in making and selecting poles…

A “free”, aggressive, high, IMPLUSED, extended Plant/Takeoff is the answer to progress in the vault… but if we don’t match that with concepts verified by physics, the correct bend, grip and strength of pole, etc.. we are missing the key “link” to vault progress.



dj

[KirkB]

Is the pole angle measured at the takeoff point on an unbent pole or not? Will the grip, the reach (on tiptoes with top hand holding at the grip point), the takeoff point from the box, and the 8" depth of the box not give you the parameters you need to compute the pole angle?

If not there, then when and where? I'm still confused as to the answer to this simple question.

I understand takeoff angle ... I'm asking about pole angle.

Anybody?

Kirk

[dj]

hey

sorry Kirk,

for pole angle... it says the instant the pole strikes the back of the box

and list these numbers for Bubka's 5.85 jump with the 6.12 max height of COM

Pole angle....28.6 degrees
Trunk angle....83.0 degrees
Relative vertical extension of the plant arm....99.4%
Horizontal position of the takeoff foot toe relative to top hand...10cm (3.9in) under
Horizontal position of takeoff foot toe relative to box....4.37 m (14' 4")
Total time of support.....07 sec

the Takeoff.. (the instant when the takeoff foot leaves the ground)

Horizontal Velocity.....8.04m/s
Vertical velocity....2.37m/s
Resultant velocity8.38m/s
Takeoff angle....16.4 degrees
Height of CG....1.29m
Total amount of energy of vaulter divided by vaulter mass....49.6J/kg
Relative amount of pole bend....1.6%
Pole angle....29.6 degrees
Trunk angle....76.9 degrees
Swing leg thigh angle....72.1 degress
Relative vertical extension of plant arm....91.8%
Horizontal position of takeoff foot toe to top hand... 2cm under/past hand
Duration of pole support....05sec (apparently this was the time of bent pole before lift off)
Duration of takeoff foot contact.... .12sec (apparently this was how long the foot stayed on the last step untill losing contact)..

the next phase is the Swing...
Mimimum distance between CG and box....2.87m (9' 4.8")
Horizontal displacement of CG during swing....2.35m (7'.8.3")
Vertical displacement of CG during swing.....92m (3' 0.2")
Duration of swing.... .39sec

then you have Rockback....

since the vaulter was "in support" before the toe left the ground and the angle is "when" or slightly after the toe leaves the ground... How do you do the math to get 16.4 degrees???

my question is...

can you get the angle, or rather what angle do you get when you use the numbers from the swing...

2.35 base of the triangle...
.92cm vertical 90 degree triangle leg
and sqauare root of A square + B square gives the hypot...

if you know the triangle measurements you can determine the 'slop" which in this case will be the angle traveled TO max bend..

help me out here

dj

dj

[billy_pacheco7]

i dont have much to say becuase this article i found says it all. I do believe there is more then one way toward the take-off theory, you just got to find the one that best suites you as a vaulter or as a coach. Though, this article gives you a new mathematical calculation, and kinetic theory to think about. You should always be open minded towards anything, especially in a technical event such as the pole vault.

-Enjoy-

http://pukashell.net/kimo/polevault/physics.html

[powerplant42]

Way beyond the scope of this thread/forum.