"Maximizing Energy in the Pole Vault" - Article

[Spencer Chang, MD]

This article is posted on PVEI.com in the What's New Section as a PDF file in it's entirety with pictures. It is listed under a gold rating as:
Document: Maximizing Energy in the Pole Vault (4/18/04)

http://pvei.com/index.php?pagename=shelf_whatsnew.php

The article is extremely technical and long, but I hope will be helpful to some of the coaches and vaulters out there. I welcome any comments or questions. The text from this article is included below.

Aloha,
Spence

Maximizing Energy in the Pole Vault

By Spencer Chang, MD
University of Hawaii Pole Vault Coach
Orthopaedic Surgeon
Sports Medicine/Foot and Ankle Surgery

Introduction

Performance in the pole vault is determined by efficiency of movements that will optimize transfer of energy in a vertical direction. For example, one might be fast down the runway, but inefficiency in the plant will result in slowing down at the most critical point, the take-off. We know from Adamczewski and Dickwach, as well as McGinnis’s work that fast approach velocities particularly from 10 m to 5 m from the plant box are necessary to vault high. However, there are numerous components of the vault, which may result in a loss of velocity, or conversion of energy to a vertical direction. The purpose of this paper is to explore concepts that will help our vaulters maximize efficiency of energy transfer in the pole vault.
The techniques described in this article are for right-handed vaulters.

The Pole Carry

According to the Petrov model, the hands should be held at a width that would be comfortable hanging from a horizontal bar. This is approximately shoulder width apart. It is also easier to swing while hanging from this position. While dangling from a horizontal bar, the distance from the hands to the feet is at its longest when held at shoulder width apart as opposed to wider than shoulder width apart. Therefore, extension at the plant is optimized with a shoulder width pole carry. This width also allows the vaulter to adequately balance the pole such that the right hand does not drift too far behind the vaulter’s back, and maintenance of a high pole carry (right hand around the waist level) can be accomplished. By doing so, positioning of the upper extremities is similar to a sprinter.

Some coaches advocate the use of a wider than shoulder width pole carry. The pole may be easier to carry, particularly for heavier, longer poles. Proponents suggest that this allows positioning of the bottom arm such that there is a mechanical advantage in initiating the pole bend. With a properly executed plant (both arms extended upwards) and take-off, it is the speed and momentum of the vaulter that causes a bend in the pole. Coaches should de-emphasize using the left arm to bend the pole and never suggest pulling down with the right arm. One must remember that with a wider grip, maintenance of a straight left arm after take-off may result in blocking the shoulder’s forward motion and retarding the swing.

The Approach and Pole Drop


In reality, the pole drop starts at the initiation of the approach. In order to maximize efficiency of movement to increase speed, the vaulter needs to eliminate excessive counterproductive motion, yet should neither be rigid. Just like a sprinter, the vaulter needs to use “reciprocal motionsâ€Â

[vaultfan]

“As the take-off step touches the ground, the pole should be in the box but not at the back of the box just yet. The arms should be raised overhead as the vaulter initiates the jump at this point. Simultaneously, as the pole tip touches the box, the arms must be completely extendedâ€Â

[Spencer Chang, MD]

The transition from plant to take off is smoother if the vaulter is already in an extended position prior to the pole hitting the back of the box. You'll be able to tell a bad plant by the sound of a loud thud if the pole only hits the very back of the box, instead of sliding into the back of the box as the vaulter jumps over the pole.

The key to getting the tip down as the vaulter extends upwards is by making the plant an upward motion of both arms. A narrower grip will also help. If you pull your pole down with the bottom arm to get the pole tip down, I guarantee you that you will have a collapsed bottom arm at take-off and not be extended as well.

Vaulters get concerned that if they start pushing up the bottom arm too soon, the pole tip will pop out the box. The amount that the pole tip slides in the box is not much. The bottom arm moving up occurs right as the vaulter is leaving his toe (following through with the plant at take-off). The pole at this point will be at the back of the box in a free take-off. In a pre-jump, the vaulter will travel in the air slightly before contacting the back of the box. The bottom arm is an action-reaction. The key is being in position to be ready for the action, i.e. straight left arm ready to resist the pole upwards as the pole contacts the back of the box.

[vaultfan]

Here are links to a topic which may be interest to those aspiring to become elite vaulters:

The 6â€Â

[Spencer Chang, MD]

You're right. I already addressed it in the article.

The picture showing the UCI vaulter shows him loading the bottom arm with a bent (collapsed left elbow). There is less power in doing this. Imagine doing the hammer throw with bent arms. Obviously, it would be less dynamic. By keeping as long limbs as possible, and rotating at the same time, moving the shoulders through this motion, there is much more power. Instead of just using your biceps, you're using your lats, triceps, deltoids, traps and torso. It's like trying to hit a baseball without putting your hips into it.

Dropping the left shoulder down as the left elbow points down as well creates a pull and increased pressure on the bottom grip, making the pole act like a stiffer pole.

Usually when you collapse the left arm (suck it in) in the top part of the vault, this releases pressure on the pole, places more pressure on the top hand as it's still relatively straight, and does the opposite of what you want to have done. The pole will straighten before you've attained an adequate position because you have released the load on the pole. Many vaulters will tend to drop out of the pole because they have not initiated the turn at this point. Therefore as you turn late, with decreased momentum in the pole, you flag out. Compensation is done by trying to curl over the bar (to allow the center of gravity to pass below the bar). The vaulter should actually be tossed over the bar. Look at video of Bubka and how he was literally flung over the bar. You never see him "piking" a lot over the bar to make it.

The key is to load the pole while getting to the right position, and let it release at the right time so it flings you.

[Spencer Chang, MD]

If you look at the UCI vaulter again, in the first image, the pole is still bent and he has collapsed the left arm. At this same position in the bend in the pole, Bubka is completely inverted and turned 1/4. You look at the next image, the UCI vaulter is now turned 1/4, but the pole is completely straight. When the pole is completely straight, you should be in a handstand. I bet he could have had a more dynamic vault, and probably had to pike over the bar.

[Spencer Chang, MD]

I do have to clarify something.

I don't want my comments to be misconstrued. You do actually pike over the bar to some degree. What I meant by my comments is "excessive piking" which comes when you lose your pole speed at the top. The picture above is an excellent example of how to come off the pole. As she drops her feet, her head and torso will rise up, allowing her to rotate around the bar.

If you lose your pole speed, you have to pike more to make the bar. So piking is not necessarily a bad thing. It either means that you are absolutely maxing out your vertical height, which is very good, or you've lost some vertical speed at the top of your pole due to some technical inefficiency during your vault. Now in the first scenario (maxing out your vertical height), you will see these vaulters piking over the bar only after they have released off of the pole. It only occurs for a brief instant, as the torso rises up and the vaulter rotates around the bar. These vaulters will often continue to go upwards after they have released off of the pole. See Toby Stevenson's 6 m vault.

On the other hand, if you're piking over the bar, it likely means that you're vaulting over your handhold, and doing relatively well.

[Spencer Chang, MD]

A slightly updated version of this article will appear in the Pole Vault Standard. By the way, everyone should subscribe to the pole vault standard.