Posted by: Jack Mankin (MrBatspeed@aol.com) on Sat Aug 20 20:13:35 2011

> Please allow me to humbly submit some tips on this topic, as I have been able to mostly eliminate this behavior in my 12-year-old's swing. Here is my kid's swing:
>
> http://www.youtube.com/watch?v=pou-NN5D_Js
>
> First, a couple of observations (just my opinion):
> 1.You let the barrel of the bat drop too much behind you prior to rotation. This will very negatively impact your ability to make vertical adjustments and to hit breaking balls.
> 2.You lose the ideal 45-degree bat tilt (from vertical, towards the pitcher) prior to rotation. The ideal 45-degree tip of the bat towards the pitcher leverages physics to help propel the bat head forward as you rotate around the core. Without this angle, you will have to engage more muscle power in order to achieve the same bat speed at the point of contact. Also, keep in mind that all things need distance to accelerate from 0 to maximum speed. You need to allow the bat head some distance as well to pick up speed.
> 3.You stretch your hands too far behind your back shoulder during the load. You see a lot of pros do this successfully, but guess what? The closer that you keep your hands to your body (and if you keep your front elbow bent at about 90 degrees), when you rotate your core and your shoulders, your hands get to the front of your body so much more quickly than if your hands start out so far behind you! This is one of the biggest contributors to your bat lag.
> 4.You allow the angle between your forearms to degenerate to much less than 90 degrees during your swing. The farther that this angle decreases from 90 degrees, the less stability the bat will have and the greater the likelihood that you will not stay on the intended swing plane.
> 5.Lastly, I don't think you are being explosive enough with your core and shoulder rotation. You seem to use too much arms and not enough torso and shoulder rotation during the early part of the swing. Fact is that you can rotate your hips, torso, and shoulders much more quickly than you can swing your arms. Also, the arms and hands should be used for a lot of the precision adjustments at the end of the swing, but if you engage your arm muscles too early, you will over-commit to a swing plane and compromise the ability to make precision adjustments before you have recognized the true path of the pitch.
> So what to do?
> 1.I think you should go ahead and practice with the elbow brace that these guys peddle; I think it's a good idea.
> 2.You will need to take a million swings on the tee and observe some of the following points:
> 1.Right up until you start your core rotation, keep the bat tilted forward toward the pitcher (and behind your head) at about 45 degrees.
> 2.Right up until you start your core rotation, keep the hands right at your back shoulder and not beyond it.
> 3.Try to keep your front arm bent at about 90 degrees through the core and shoulder rotation and only extend at the last moment to contact.
> 4.Do not allow your hands to drop below breast level at any point during your swing.
> 5.Keep both of your elbows at the same distance throughout most of your swing (except for the extension to contact).
> 6.Keep your hands right at your shoulders until you have rotated the torso and shoulders such that your hands are in front of your body.
> That's it! My humble opinion. Good luck!!!
>
> Chris

Hi Chris

Thank you for your appraisal of good swing mechanics. Although I agree with most of your points, I must caution you regarding your reference to "extension to contact." - It is more productive to think in terms of the bat's momentum pulling the arms "to extension after contact" rather than using the arms to "extend to contact." The role of the arms is to apply torque (push/pull of the forearms) to rotate the bat-head around the hands -- not to extend the hands forward.

Data we collected from a Motion Study Computer show that although the bat-head reached a velocity of 78 mph, the hands maximum velocity was 14 mph. Actually, the 14 mph was reached midway through the swing and slowed to 6 mph at contact. -- Extending the hands approaching contact has a negative effect on both the CHP and torque applied (BHT in this case).

If I had to choose the single biggest contributor to the "bat drag" I find in my students, (angular acceleration of their bat not staying in sync with body rotation) I would say it was their allowing a boxed-lead-elbow to straighten approaching contact. When this happens, the lead-shoulder can rotate 90+ degrees without the bottom-hand applying any significant force to the bat.

Basically, lead-shoulder rotation is just wasted taking up the slack from the arm straightening out rather than applying a strong rearward pull at the knob (BHT). Without efficient use of the lead side, the batter is left with a longer back-arm-push type swing. -- To make efficient use of the lead-side, the bend in the lead-arm must remain constant from initiation through contact.

Since this is a very important point to rotational mechanics, I will post video when I get back that covers the role of the lead-arm in more detail.

Jack Mankin