FATS

'force across the shaft'

Some time ago it was the fashion to consider the right hand/arm to be the bad villain in the golf swing and almost exclusively a lead side dominant swing was being taught.  Then came along Homer Kelley with TGM and now swinging and hitting were supposed to be mutually exclusive. However interestingly a contemporary of Homer Kelley, and equally well known golf instructor, Paul Bertholy, maintained that a golf swing is truly a bi-arm sport with the right arm hitting at the proper time, i.e., just before impact.

Brian Manzella teaches a sequential action of first pulling from the top and subsequently, when shaft vertical, a subsequent vigorous contribution from the right arm. It is being referred to as FATS, meaning 'force across the  shaft'. However the right hand can push on the shaft in various ways. It can be a push due to straightening the elbow, a radial type of action, or it can be more of a tangential action, hitting with the whole trail arm, kept bent like a dog's hind leg at elbow and wrist (Bertholy, claw).

It is instructive to have a closer look what actually goes on in downswing when a force is applied by the right side onto the shaft. I do feel that hitting, pushing with the trail arm, and swinging, pulling with the lead shoulder, are not that far apart even if they are associated with quite distinct feelings. Let's look at Figs 1 and 2 in which is decomposed a pushing force F exerted by the trail arm onto the shaft. The single pushing force F is equivalent to the separate application of forces F1 and F2.

The force component F1 exerts a torque, Torque1, with regard to the joint at B and similarly the force F2 a torque, Torque2, with regard to the lead shoulder joint. Notice in Fig2 that Torque2 can get negative, depending on the angle between the pushing force F and the club shaft. Also note the importance of the separation L1 between hinge and point of application of pushing force. When pushing with the heel pad it can be made very small and torque T1 reduces substantially.

Therefore one can consider a linear pushing force on the shaft by the right arm to be equivalent to the action of two torques, Torque1 and Torque2, which act respectively on the club shaft and on the left arm. Hence pushing is really equivalent to swinging, with a bit of wrist torque added, as shown in Fig3 - a linear force acting at A, as detailed above, being equivalent to torques acting at joints B and C.

I have some reservations about emphasizing too much pushing out to straight for the right arm trough impact as is seemingly the TGM approach.  It tends to increase the swing radius and constitutes a power leak. This emphasis on both arms straight past impact looks perhaps pretty when posed but it can't be considerd an efficient power move. A certain amount of trail arm flex seems to be common trait of many professional golfers.

It seems to me that hitting with the whole trail arm, kept bent like a dog's hind leg at elbow and wrist (claw), with no effort being made to straighten it, using a strong rotational core action, using the ground as a base, and striving for 'connection', acts, via the shoulder girdle, positively on both shoulders, seems to me more indicated. The late and well respected Paul Bertholy did teach keeping the trail arm bent very late into the downswing to explode only at impact.

As an aid for possible discussion I have included Fig4. The trail arm can straighten between A and E. The torques exerted at the joints E and D also result in a pushing force acting at A.  Hence a radial vs a tangential type pushing force. Moreover the effectieve pressure point on the shaft at A can be underneath the trail heel pad, to minimize wrist torque on the shaft or alternatively being purposely shifted more out towards the index finger, opening the angle between lead arm and clubshaft a bit faster, perhaps to get better clubhead impact alignments.

mandrin