Posted by: Dr. David Chambers () on Fri Aug 1 05:52:18 2003

Hi All
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> The board is starting a new month but I think July produced many interesting discussions. I am gratified that although there were many varying viewpoints, few took opposing views personally. This allows many readers to be enlightened by your discussions. I still plan to commit on some of the threads in this month -- Barring arm Sid Tue Jul 29 19:18:59 2003 -- & -- atn: jack: video analysis bart Tue Jul 29 13:48:07 2003.
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> Below is a post I am making to another interesting July thread. Go to -- Dominant Hand dougdinger Sun Jul 20 17:47:44 2003 – if you would like to read the total discussion.
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> Jack Mankin
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> From: Dr. David Chambers
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> >>> Thank you for your response. I agree that the changes made by athletes is in their swing mechanics when they begin to struggle. In fact, I agree that the complexity of the swing as labeled by hitting instructors invalid. The human body does things naturally based upon the physically ability of the individual. Instructors try to take a natural movement and make changes to it without regard for the individuals strengths. My comment about the similarities of swinging a bat and throwing a ball are very well thought out and accurate. A right handed side arm throw (similar to skipping a rock across a pond) requires identical mechanics to a right handed batter. the hips begin to rotate, followed by the back elbow which pulls the hand and ball (or bat) and is more accurate. it also gives the athlete more control. Simple knowledge of neuromuscular recruitment and coordination contribute to our knowledge that we all have a side that is stronger and more coordinated than the other side. If this were not true the you, Mr. Mankin could throw a ball the same distance in any manner with either hand. We can look at video and see what ever we want to see. <<<
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> Hi Dr. David Chambers
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> In the discussions below your post, many have offered a valid argument that in the baseball swing, the lead-elbow should not lead the hands as in throwing a ball. However, in fairness to you, I would point out that while doing video Swing Reviews, I have noted that a number of young hitters had the elbow lead their hands as in throwing a ball. This may have been their natural movement but it did not produce the beneficial results you indicated.
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> As you stated, the elbow leads and the arms pull the bat through. But the added inertia of the bat (as compared to a pebble) causes the elbow to then slide in toward the bellybutton. As the elbow and forearm slides inward, the path of the hand straightens and there is no circular hand-path as there would be in skipping a rock across a pond. This is also a weak position for the batter to apply torque to the bat and the end result is a poor baseball swing.
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> There is a type of sidearm throw where the elbow need not lead the hands and could resemble the top-hand movement of a hitter swinging with top-hand-torque. This could occur as a catcher makes a quick (remains facing the pitcher) sidearm throw toward first base. When throwing sidearm in this direction, the elbow is forced in toward the catcher’s side (instead of toward the pitcher) and rotates there without leading the hands. The hand starts up near the back-shoulder, then circles back and downward similar to the motion of a batter using THT.
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> Jack Mankin

Thank you Jack.

You make a somewhat valid argument, but I think you are missing a small detail. I experimented today with your analysis and came up with a different assessment of the same motion. You stated.... "As the elbow and forearm slides inward, the path of the hand straightens and there is no circular hand-path as there would be in skipping a rock across a pond. This is also a weak position for the batter to apply torque to the bat and the end result is a poor baseball swing"
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According to my tests, the path of the hands does not straighten due to the continued rotation of the torso, which keeps them on a circular path. In my findings, once the elbow has gotten into the "slot posiiton", the hands appear (to the naked eye) to take a linear path.

Under closer review and at higher speeds, the researcher can see that the path of the hands only appears to be linear because the arms will begin to straighten. This occurs as the release of energy in the arms transfers to the wrists and subsequently the out the end of the bat.

To the naked eye and under analysis at 30 frames per second, this is what many have mistaken as linear hitting. If an object moves at 360 degrees per second, my analysis of the object at 30 frames per second could cause me to miss over what happens for over 12 degrees of movement. the elbow moves at over 600 degrees per second and the hands at over 900 degrees per second. At 30 frames per second, I will miss over 20 degrees of movement. Depending upon the distance from the axis of rotation to my point of measurement. That could mean that I may miss anywhere from one inch to ten inches of movement.

(Even the model video you display on this site can be referenced) Add up the lost frames in your model and we have lost over 2/3 of what is happening in the swing. In Frame C (frames 2/3/4 under normal play), you model's trailing elbow spends time in front of the trailing (top) hand. Because of the speed of travel, it quickly catches back up to the elbow and passes it in position.

I have seen many discussions about "torque" Which appears to be misused. The torque many are referring to is mistaken for the energy release. The role of each major body segment in the swing is to store and release energy it is the storage of energy that is the torque (loading of a joint).

In my explanation of lead elbow/hand position a greater amount of torque is placed on the wrists, thus creating a greater potential release of energy to the bat. Many would call this a weaker position for hitters. but if the hitters has developed an appropriate amount of strength in their hands/wrists/forearms, they can actually control the release of energy more efficiently.

If the hand leads the elbow, a lower amount of energy is stored in the wrists on the way the contact. The excess energy is thus stored in the shoulder and elbow. This can create tension in the wrists/hands. The athletes inability to release the energy stored in these joints can contribute to physical problems in those joints. We see similar problems in throwers who do not release the energy in the shoulders and elbows in pitchers who get into less efficient throwing positions.

There can be a negative impact to these mechanics in hitters and pitchers/throwers. If an athlete has hypermobility or intentionally increases the stretch length in the joint storing energy (as in Epstein's call for more X-factor--separation between the hips and shoulders), injuries can result because the energy will continue to store until it reaches the maximum for that joint. The joint then has to be strong enough to recover from the excessive stretch position. The bottom line is the athletes have to be strong enough to handle what we teach.

In response to the questions from the other gentlemen, I am not referring to any one hitter in particular. Most major league hitters do not necessarily have the best mechanics. So if we model young hitters after one player or another we may be setting them up for failure. Most scouts will look at a player and say he swings like Bonds, A-rod, or somebody that they like and thats how they determine (along with their stats) is a first of last round pick. that player may or may not make it in the big leagues because they do not have the same mental preparation, pitch selection, and many other factors that helped other hitters with similar swings be successful. A young hitter with a hole in his swing, may not pick up on which pitch to hit or know how to work around the weaknesses. And that's why scouting, just like hitting can be a guessing game.