The Pike
Posted: Thu Dec 10, 2009 1:28 pm
A few things have got me thinking if the pike has more of a use in pole vaulting than avoiding the cross bar and if it has more of a scientific backing. In the thread about Bubka's 5.85 jump it said that his center of mass was at about 6.12m, and someone comment that if he was in the pike position than his center of mass would be under the bar. This is because when you are folded in a pike your chest, legs, arms are hanging under the bar.
The scientific backing to why a good pike might make you jump higher comes from the fact that your potential energy at the top of your vault is determined by MGH (mass*gravity*height). But height is not how high you jump, it is how high your center of mass is. And since it requires more energy to get your center of mass up higher, than just by piking, you can increase your vault height.
For example if I try to jump a bar and go vertical and come straight off the top of the pole but do not pike and kind of flatten out at the top, I am having to raise my entire body over the bar, and my center of mass has to be close to the same height of the bar if not higher. Now with the same exact vault, but with a pike, my center of mass would go to the same height as the previous jump, but because I am piking, there is never a point where most of my body is above the cross bar, allowing me to jump over my center of mass....
just a thought....
The scientific backing to why a good pike might make you jump higher comes from the fact that your potential energy at the top of your vault is determined by MGH (mass*gravity*height). But height is not how high you jump, it is how high your center of mass is. And since it requires more energy to get your center of mass up higher, than just by piking, you can increase your vault height.
For example if I try to jump a bar and go vertical and come straight off the top of the pole but do not pike and kind of flatten out at the top, I am having to raise my entire body over the bar, and my center of mass has to be close to the same height of the bar if not higher. Now with the same exact vault, but with a pike, my center of mass would go to the same height as the previous jump, but because I am piking, there is never a point where most of my body is above the cross bar, allowing me to jump over my center of mass....
just a thought....