Posted by: Shawn () on Tue Jan 25 19:02:28 2005

>>> There is something else going on during this point in the swing. The hips and shoulders decelerate sending the arms ahead of the hips. It's called the whip affect.
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> I have several views of the same swing from the back and side views and they tell different tale. The riew view it look like the hook affect is how you explained it. In the side view you can see the whip affect and the arms accelerated past and around the rotating body. <<<
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> Hi Shawn
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> I stated in a previous post that I had no problem with calling the flinging of the hands into a circular path a whipping effect. I do have a problem with some of Dr. Yeager’s conclusions regarding his definition of a whip effect.
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> He states, “If forward momentum is not stopped and if body segments turn at the same time, maximal energy transfer will not result. If one were to attempt to crack a whip by rotating in a circle without stopping the hand, and therefore not transferring energy, the goal of cracking the whip would not be attained. However, if we stop the whip and then allow the whip to sequentially stop down the line, then we'll get the desired result.”
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> You just stated, “The hips and shoulders decelerate sending the arms ahead of the hips. It's called the whip affect.” According to Dr.Yeager, the transfer of energy from the whip does not occur until hip and shoulder rotation has stopped (“if we stop the whip and then allow the whip to sequentially stop down the line, then we'll get the desired result”). This is true when cracking a bullwhip but is it a correct analogy for swinging a ridged bat – I think not.
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> By the definition of his analogy, there is no transfer of energy to accelerate the bat around the swing plane until the shoulders stop. I would contend just the opposite is true. I would say that when the shoulder stops (105 degree position), the bat should have already been accelerated to contact – not just starting to accelerate.
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> He states, “If one were to attempt to crack a whip by rotating in a circle without stopping the hand, and therefore not transferring energy, the goal of cracking the whip would not be attained.” I agree, you do not “crack a whip” by keeping the hands accelerating in a circular path. However, unlike his “whipping action”, an angular displacement rate of the hands does induce an angular displacement rate to a ridged bat in the baseball swing from initiation to contact. Like swinging a ball around on a string, you do not need to stop the hand to accelerate the bat-head.
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> Jack Mankin
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You know Skilltech as a good example of the kinetic sequence with a softball/fastpitch example. In it you will find accelerations and decelerations of the swing, when and where. Like any sequence it acts in a sequential fashion. You can see the how the sequence works from acceleration to decelerations.

I definitely see the hips and shoulders decelerating and the bat being accelerated. The shoulders might follow through due to momentum, but this is after deceleration takes place.

The whip affect is a biomechanical principle. It helps explain the kinetic sequence of the swing. Why it acts in a sequential fashion both through the acceleration and deceleration phases. It helps explain how momentum is transfered in the swing. I think you are to tied up in the hands coming to a stop to crack the whip, what about the hips decelerating??

"""By the definition of his analogy, there is no transfer of energy to accelerate the bat around the swing plane until the shoulders stop. I would contend just the opposite is true. I would say that when the shoulder stops (105 degree position), the bat should have already been accelerated to contact – not just starting to accelerate."""

I don't know if I'm following what your saying. The shoulders slow down transfering their momentum to the bat. They might not stop completely even if it looks that way on video.

look at skilltechnologies.com down the free sports player, check out the softball kinetic sequence and we can further discuss accelerations and decelerations in the swing.