Is Pushing with the Bottom Arm Good or Bad?

[Riley Crosby]

http://www.youtube.com/watch?v=hvf3PQeT ... re=related

in that video it looks as if he has a stiff left arm. tell me if im wrong.
-Riley

[KirkB]

You're wrong.

It's a terrible vault to study, but nevertheless, you have to look at his bottom arm when he's in the C.

Do you see that it's directly above his head, with his elbow bent? He's let his bottom arm collapse (a good thing), as he drove into the C position. That verifies that his arm isn't stiff (a stiff bottom arm is a bad thing - if you're trying to follow the Petrov model). If it was stiff, there would be a lot more distance between his head and his bottom hand.

Once he passes thru the C position, yes, his bottom arm APPEARS TO be pressing. But remember that he's already loaded the pole significantly by that point in time, and so the pole's already bending due to the force being applied to it thru his TOP arm.

Also notice that he swings out of the C quite fluently (even on this bad vault). If he had blocked with his bottom arm, his entire body would have stayed behind the pole longer (a bad thing).

However, he doesn't come out of this swing very well, and the foot of his trail leg almost hits his top hand. His hips were too low. Terrible, terrible.

Look at this one instead: http://www.youtube.com/watch?v=DYaBPDTrVuI&feature=related

Notice how the foot of his trail is quite a bit higher than his top hand at the comparative frame to the other vid? Notice that his hips were quite a bit higher in that comparative frame? This is a very nice vault!

Now look at his C. Notice how the arm collapses? Then as he comes out of the C, notice how the pole moves away from his bottom arm? This gives the ILLUSION that he might be pressing, but in reality, the pole is already bending due ONLY to the force of his run and takeoff thru his TOP hand.

This particular issue is almost beaten to death on this forum, yet it still remains controversial. [sigh]

I'm repeating this for you, Riley, because I know that you're just beginning to educate yourself by browsing for good vids to analyze, and by asking good questions - albeit already asked and answered.

Keep researching, keep browsing, and keep asking!

Kirk

[golfdane]

If we wanna examine the jump suggested by Riley, please use:
http://www.stabhoch.com/movies/20000922_Bubka_610trng_rl.mov
http://www.stabhoch.com/movies/20000922_Bubka_610trng_lr.mov

It's the exact same jump from both sides. It's quicktime, which allows you to forward frame by frame.
I just love this site (http://stabhoch.com). Too bad no new jumps are submitted.

http://www.stabhochsprung.com/compare_2_movies.htm
Add the 2 jumps by Bubka (scroll down to 2000), and you'll get a side by side view. You can syncronize the movies by dragging the slider to a fixed point (take-off), and now step forwards and backwards frame by frame.

Elbow CLEARLY bent.

[golfdane]

Look at this one instead: http://www.youtube.com/watch?v=DYaBPDTrVuI&feature=related

Kirk

Definately an all-time favorite youtube!!

[dj]

hey golfdane

i think this is as perfect as it gets... definitely doesn’t look like a “push” with the front (left) arm.. nor a “pull” at this point either.

looks to be exactly how Petrov describes the “Petrov” model.

But at this point I do think the “pull” is just about ready to happen.. it should happen just as the hips are “engaged” to make the trail foot start it’s “sweep”..

We also need to remember these pictures are "still" frames and it only takes a world class vaulter .50 (one half) of a second to go from Take Off to “the back flat to the runway” position. So there is no time to say “One thousand and one”… just “One thou!” To complete a whole vault it takes about 1.45 seconds for 19-8/20 foot jumps. 40/42 frames on a standard camera.. 14 for TO.. 14 frames for “invert” and 14 frames for “push off”. Not a lot of “waiting” time anywhere. Therefore the “Continuous Chain”.

I do think at this point there seems to be a little front arm/hand support with the “ball” of the left hand.. but very little. And it is so fast and subtle it would merely feel like wiping sweet from your forehead, If anything was felt at all.

If you look at the left “grip” the last two fingers are not grasping the pole.. so no intended push..or pull.. this is exactly what Roberts, Bell and Tully described when they did it right. Swing from the top hand with the thumb and forefinger of the bottom hand the only “grip’ by that hand..

You don’t seem to have a need to “grip” a high bar to do a gaint so it seems “cupping” the hands and swinging “LH” should get the job done on a properly bent pole.

dj

[KirkB]

Good point on the clasping of the bottom hand, DJ!

Let's not forget Lukyanenko's pic on this thread (near bottom of page), which enforces your point:
http://polevaultpower.com/forum/viewtopic.php?f=38&t=14525&p=112251&hilit=lukyanenko+kirk#p112251

Kirk