The plant (in my world) ends as soon as the foot touches the ground. Where your pole is at that time is crucial. It must be far enough from your body in order to have room to perform a free take-off. The jump begins after foot touches the ground. Let’s not mix the two.
I Agree with the definition and statement.
All I am trying to say that the pole must have enough time to freefall. (freefall is the fastest and most economical way to descend the pole into the box) The elite vaulters usually cover last six steps in 1.3 sec +/-, so the drop has to begin at around 6 steps.
No problem here I agree.
"You can have extended arm without locking the elbow or sacrificing the distance. This is the natural flex that Petrov described. I do not think Petrov suggested to flax arm close to the chest. The reason I say it does not seem that the issue was clearly identified by them is precisely because they leave it to interpretation as far as distance from the chest. Well I hope I persuaded you that the bigger distance is more advantageous for performing the free take-off."
Your statement about the extended arm without locking the elbow I accept. I do not understand "... or sacrificing distance"
In terms of what Petrov says I quote from Petrov's article "Pole Vault - the state of the art.New Studies in Athletics, 2004, 19(3), 23-32.
page 30 "The drop must not be abrupt(if the vaulter was not late in initiating it) and it must fall within the rhythm of the last strides.
In the last steps of the drop, the vaulter should not "lose" the pole by stretching the left arm forwards (as if looking for support or the box). All movements during the drop take place while the left hand is kept over the left elbow."!
The Geometry of the situation in regard to creating space for the vaulter to execute a free take-off suggests that the optimal solution is not to either extend the left arm forward towards the box or keep it flexed close to the chest. The mathematical solution to optimizing the space in which to execute the free take-off is to move the left arm slightly forward whilst continuing in a predominantly upward pathway in concert with the right hand.
To fully extend the left arm from the shoulders reduces the amplitude of the space (defined by the apex angle of the vaulter,pole ground triangle),
causes excessive advance of the take-off foot in front of the vaulter's centre of mass at take-off initial contact, lowers the centre of mass and creates more work for the vaulter in the transition into the take-off.
I remain to be convinced.
I do want to know more about the solution to the transition problem in the plant. I cannot see how the extended left arm promotes a free-take off. I see it still as contributing to being under. I look forward to enlightenment
