I just finished some video analysis of a few of my students swings and answered e-mails regarding questions on how to improve lower body mechanics. Although I agree with them that getting the hips to rotate properly is very important, I think we are getting the cart ahead of the horse. The ultimate purpose of the swing is not to rotate the hips -- it is to rotate the bat-head.
It is obvious from reading the discussions and analysis of swing clips that most coaches think they must first perfect a batter's lower body mechanics before addressing how his upper body accelerates the bat-head. I have found just the opposite to be true. When a batter concentrates of initiating the bat-head acceleration correctly, the timing and force of hip rotation is activated to support that mission.
When the batter's Main concentration is on getting the hips to rotate ahead of the hands, the bat-head can fall behind the rotational power curve. Below are a couple of my replies to e-mails regarding this topic.
Thank you for sending the clip and Tony's narration. I have found from doing hundreds of video analysis of young hitters swings that the key to their improvement is not found in first addressing their lower body mechanics. The lower body tries to provide what the batter's upper-body mechanics demands to swing the bat.
Bonds first accelerates the bat-head rearward. Therefore, his lower body mechanics are supporting that action. I see different lower body mechanics when the batter is thinking of driving the hands forward to initiate the swing. When I can get a student to initiate the swing correctly with the upper body, his lower body mechanics automatically changes to support that action without any input from me.
Note in the clip below of Sosa and Strawberry that the bat-head starts its' rearward acceleration well before hip or body rotation is initiated. Even when the batter does not apply pre-launch acceleration, if his concentration is "Hips first," body rotation and the acceleration of the bat can get out of sync. I refer to this as "disconnection" or 'falling behind the power curve.' It is important to keep in mind the ultimate purpose of all swing mechanics is to rotate the bat -- not the hips or hands.
Think, Bat-Head - Hips or Hands First??
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Thank you for your email and your continued support of BatSpeed.com. Please feel free to use the Swing Review Analysis you have on file at any time. On one hand, the kids need to have fun and develop a love for the game. On the other hand, with baseball now beginning at such an early age (Tee ball at 5 & 6) we don't want the younger age group to be left behind. I do not feel 8 years is too young to begin teaching Rotational Mechanics.
By far, the most important part of the swing is how it is initiated. How the batter initiates the swing produces trajectories of the bat and limbs that determines the balance of the swing. THT is the key to initiating the swing correctly. It basically accelerates the bat-head into the swing plane instead of driving the knob forward.
I think reviewing this clip from the PathFinder DVD
may give you a better understanding of THT.
In addressing your back issue, I suggest you first get proficient in applying THT from the normal launch position (bat behind the head). I find that most batters who start with the bat cocked forward and apply pre-launch THT do not sweep the bat head cleanly behind the head into the swing plane. They normally accelerate the bat-head too vertically and it cuts down through the correct plane. This places great stress on the wrist and back muscles.