Eva Voortman - Insideout softball science, May 2020
Gooien, smijten of werpen? Pitchen van top tot teen naar de top - Fase 4 landing stride leg to release
What do you need to throw hard? Well actually, everything. From the big toe of the push-off foot, to the hand in your glove, and from the toe of your landing foot to the fingertips of your pitching hand. To accelerate the ball in an optimal way, you need the fingers of your pitching hand to go as fast as they can, and this acceleration literally comes from your big toe. The reasoning behind this, and how you can accelerate your body from that toe to your fingers is what I will explain the coming weeks along findings from scientific articles combined with my experience as a pitcher(trainer). This week: landing stride leg to release
The beginning lies at the finish. That is how the previous article ended, and it is how this one begins. It is a little unusual to start with the finish. The reason to do it anyways is the emphasis the fourth phase deserves. The fourth phase is the most important phase, this phase determines how much energy is transferred from the body to the ball(velocity). You could say the first three phases charge the body, and phase 4 transfers the generated energy to the ball. Simply put, the first phases are not worth a whole lot if the last one is not executed right.
So, phase 4, landing stride leg to release. The landing of the stride leg is an important factor for the progress of the kinetic chain. Oliver and Plummer (2011) and Seldon (2015) did research looking into the ground reacting forces of the stride leg. The ground reaction forces are the forces that work from the ground (through the landing) on the body. The vertical (Oliver and Plummer, 2011 and Seldon, 2015) as well as the horizontal ground reaction forces (Seldon, 2015) showed a correlation with ball velocity. Notable, Seldon (2015) also found, a weak, correlation between ball velocity and the speed of the build-up of the ground reaction forces. Which means, how quickly the forces were absorbed. Even though it is a weak correlation, it is quite interesting that again the timing of the elements seems and important factor.
Logically, for the arm velocity there is a correlation found with ball velocity (Malek et al. 2015) in the fourth phase. Notable here is that Spomer et al. (2001) did not find a difference between pitchers who threw with low-velocity and high-velocity, when it comes to joint flex angle velocity. Oliver et al. (2010) looked into the rotation velocity of the throwing arm in correlation to ball velocity. A difference appeared between the unexperienced pitchers with the medium experienced pitchers and the experienced pitchers, but between the medium experienced pitchers and the experienced pitchers no difference was found. This might be were trainers may find their role, in enhancing the quality of the training hours (experience).
This was quite a quick transfer from arm velocity to the role of trainers. Let us just take a moment back into the chain. The chain is initiated from the landing of the stride leg and ends with ball release. If we take the findings that said there is no difference between medium experienced and experienced pitchers, apparently the number of training hours alone does not make a difference in ball velocity. Higher quality practices could make the difference here.
So, trainers, what can they do? The most important thing, what hopefully stands out from these articles, is the use of the entire body, the aspects that it has and the focus, mainly, should be on phase 4, the moment the kinetic chain is applied.
As hopefully also becomes clear now, quite a part of the previous articles actually talked about phase 4 of the throwing motion. The next article we will go to phase 1, the right start for the optimal pitch. Why from the end straight to the beginning? Well, a good beginning is half of the work (a Dutch saying).
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Until the next one!
Malek, Alexander, Andrew Gibbons, Sherry Backus, Howard Hillstrom, Stephen Fealy, en Andreas Kontaxis. „The Effect of Shoulder Kinetmatics on Pitch Velocity and Accuracy in High School Softball Pitchers.” The Effect of Shoulder Kinetmatics on Pitch Velocity and Accuracy in High School Softball Pitchers. Washington: George Washington University (2015). 1.
Oliver, GD, PM Dwelly, en Y-H Kwon. „Kinematic motion of the windmill softball pitch in prepubescent and pubescent girls.” Journal of Strength and Conditioning Research 24, nr. 9 (2010): 2400-2407.
Oliver, G. D., & Plummer, H. (2011). Ground reaction forces, kinematics, and muscle activations during the windmill softball pitch. Journal of sports science , 29 (10), 1071-1077.
Seldon, M., Hodapp, B., & Fischer, D. (2015). The relationship between ground reaction force and softball pitch velocity. International Journal of Exercise Science , 12 (1), 24.
Spomer, S., Conley, C., & Bird, M. (2001). A comparison of high and low velocity pitchers in fastpitch softball. A comparison of high and low velocity pitchers in fastpitch softball (pp. 112-115). University of San Francisco: Biomechanics Symposia.