In episode 6 of the @Topvelocity #PitchingTips Show we discuss what your legs and hips should be doing and how that transfers to the throwing arm. Both legs have an equally important job in the pitching delivery. There are two drives in the pitching delivery, the back leg drive and front leg stabilization, which is also technically a type of drive. Both are crucial to creating the rotation and stabilization of the hips. The legs and hips are obviously also extremely important in transferring the energy from the lower half to the upper half and creating forward trunk tilt. Forward trunk tilt then leads to external rotation which is the laying back of the arm that we talk about in the video. The biomechanics of the body all need to work together to create throwing velocity, but we will take a closer look at what the legs and hips need to do create high velocity.
Developing Leg Power for the 90mph Pitcher
The legs need to be powerful for any of this to work. In order to drive and stabilize like a high velocity pitcher you need to have the leg power. At Topvelocity we recommend our athletes have a 1.5x your bodyweight power clean or a 30+ inch vertical jump. Typically once an athlete reaches this level of power is when they start being able to drive their back leg with enough force and they are able to stabilize the force they create with the front leg. When both of the legs are doing their job this will substantially help the hip rotation. The beginning of hip rotations starts with the drive leg driving the hip linearly and then the leg going into internal rotation. Once the front leg lands and stabilizes, high velocity pitchers begin to extend the knee back towards their bodies. Combine this with the back leg drive and you have an effect that maximizes hip rotation.
Once an athlete has mastered the lower half they need to understand how to transfer the energy they have created from the lower to the upper half. This is done by hip to shoulder separation. After the lower half has done its job and the hips are open, but the shoulders need to stay closed in order to create as much torque as possible. This is hip to shoulder separation, which is one of the most important pieces to the high velocity pitcher. Once the front leg stabilizes and begins to extend back a very quick movement occurs where the shoulders begin to turn and the trunk travels forward over the front leg. As the trunk is traveling forward this gives the arm another chance to load. This is when you see the external rotation or lay back that we talk about in the video.
In conclusion, an athlete needs to develop the leg power of a high velocity pitcher. Once the leg power is developed the athlete needs to learn how to drive off the back leg and then stabilize the energy with the front leg and redirect it back into the trunk. As the athlete is creating the energy in his lower half he needs to counter rotate the upper half to create as much hip to shoulder separation as possible. When the shoulders begin to turn and the trunk begins traveling over the front leg, the arm begins to lay back into external rotation. Finally, it goes into ball release and if done correctly you will have yourself a high velocity fastball and limit the amount of stress you place on the arm.