Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Feb 13 10:47:43 2007

“How do you help a 14 year-old eliminate "bar arm", and teach him to keep his hands inside the ball? We've tried everything, every drill, etc., but the muscle memory is truly difficult to overcome.”

Hi Jim

I would suggest you make sure your concerns are a problem before changing his mechanics. – Below is an exert from an article I wrote on “Linear vs Rotational” mechanics.

Jack Mankin

##
By definition, “linear” refers to energy directed forward in a straight (A to B) direction. With linear principles, the energy for the swing is generated from kinetic energy developed from the batter Shifting Weight forward to a firm front side. The hands are extended A to B and kinetic energy is then transferred into bat speed from a “whip” effect as hands reach full extension.

With linear principles, forces applied by the hands at the handle from the hands have no impact on bat speed – in other words, torque is not a factor in generating bat speed. This is very different from Rotational Principles.

Recapping the difference between Linear vs Rotational - Linear principles rely on weight shift and an (A to B) extension of the hands to produce a “whip” effect – Rotational principles rely on the Pendulum Effect of a CHP and Torque to rotate the bat-head.

For decades, almost all batting instruction was based on this linear theory. Batters were told that when they transferred their weight forward to a firm front-side and extended their hands, there would be a “whip effect” that accelerated the bat (like popping a towel).

Believing in the “whip theory”, a host of linear cues were developed to re-enforce the straight extension of the hands & knob, i.e.
-- Don’t “bar” the lead-arm
-- Take your hands A to B
-- Knob to the ball
-- Keep your hands inside the ball
-- Don’t release the bat-head too soon

These were also the batting cues used by most MLB Coaches. However, by the late 1980s, VCRs were becoming available with frame-by-frame capabilities. MLB hitters found they no longer had to rely on the old batting cues and principles they were taught. They were now able to study the swings of the top hitters and emulate the mechanics they exhibited.

As a growing number of MLB players began to analyze the mechanics of the best MLB hitters, it became evident to many of them that the top hitters were exhibiting very different swing mechanics than the linear principles they were taught. In fact, they seem to be breaking all the old rules – many were barring the lead-arm, -- casting their hands in a circular path, spinning their shoulders and etc. Yet, they were consistently creaming the ball. -- They also found that by emulating the rotational mechanics in their swing, their performance numbers also began to jump.

As we demonstrated many times at BatSpeed.com, there is no “whip effect” of a bat when the hands are extended in a straight line. The bat is ridged and cannot whip like a towel. The bat-head must be swung around with a Circular Hand Path. --- All great hitters rotate their hands in a Circular Hand Path and apply torque (THT& BHT) at the handle.