What is the Purpose of the BACKSWING in golf?
Collective comments of golfers from 3 facebook groups:
A scientific response to this poll:
It is scary that we, as a group of golfers and golf instructors do not reach consensus, and really do not know the purpose of the backswing in golf. Responses were so diverse that even after an attempt to group similar ones together there were too many.
It is important for all golfers, but especially for instructors to understand what the terms energy (potential, kinetic), power, momentum, torque, leverage actually mean.
PP in bold stands for POINT to PONDER so that the reader may re-consider the purpose of the backswing with regard to a specific topic.
Basically, OF COURSE the full-swing backswing is designed to put a golfer into ‘position’ (what a cop-out to merely say that!). BUT FOR WHAT exactly (other than ‘for the downswing’ – another ‘cop out’!). Specifically for the downswing to deliver the club for straight direction and maximum distance, MAINLY BY achieving the most important of the ball flight laws – the INSIDE PATH.
You might interject, “So the path will help with direction but what about club speed?”
ONE – and ONLY ONE – downswing body SEQUENCE, is capable of SIMULTANEOUSLY generating both inside an path AND maximal club speed (see this reference to learn more: http://coewww.rutgers.edu/classes/mae/mae473/golf_biomechanics.pdf).
That is one with a proximal (lower body) to distal (upper body, arms and finally club) body motion pattern. ONLY this sequence can give a golfer both straight distance and maximum possible direction.
Note that this correct ground-up sequence is able to harness external forces better (ground reaction force, mainly), so that less muscle-force is required to be generated by the golfer.
PP1: So, WHICH body/arm POSITIONs of the backswing are ‘PROPER’ for the production of a good downswing SEQUENCE?
PP2: If the purpose of the backswing is to store ‘POTENTIAL ENERGY’ (PE), what precisely is potential energy? PE can be of several types – ‘gravitational potential energy’ (GPE), and ‘elastic/strain energy’ (SE) amongst others. GPE is the energy stored in an object by virtue of it’s position (away from the Earth’s center), so that an object placed at a height of 5’ has more GPE than one placed at 3’ from the ground. The height of the hands above the ground is an indication of stored GPE. Similarly if the body is fully ‘wound’ it just might have the ability to ‘unwind’ and release the SE it has stored.
Look at the orange-and-stick experiment below to understand useful and meaningless GPE. Past about 10 o’clock in the backswing, GPE is stored so the orange can only fall off the stick in a USELESS direction. In other words, WORK must first be done against gravity to bring the club to a position of USEFUL (ie in a targetward direction) GPE.
‘Coil’, ‘rotation’, ‘torque’ are all words used (sometimes inappropriately) to describe rotary or twisting motions, which are believed to store SE via muscle stretch. However, here, a meaningful direction of ‘unstoring’ is on a horizontal plane, which also harnesses the horizontal element of ground reaction force. So that unless there is a purely horizontal element to backswing rotation, downswing ‘unstoring’ (as in the typical golf swing) will be in a downward (towards the ground) direction.
Try this drill to understand why the typical golf backswing is not a true coil. Stand upright, with the feet slightly apart and the arms by your sides. Now twist everything from the ankles to the head (yes the eyes too). THAT is a twist, around an imaginary vertical axis, just like the top on the left, in the picture below. Now put your hands on your hips and side-bend to your left. Then ‘rotate’. What you’re doing (as in the typical golf swing) is really mostly a side-bend -not a pure twist – followed by an ‘un-sidebend’ – NOT a rotation/coil for storage of useful elastic energy. More like the top on the right.
PP3: Loading. This term strictly means adding a resistance or weight. Muscles do not load, they only create tension. Weight-shift could be considered adding weight to the trail side, and is useful only if ‘un-load’ happens in the correct kinematic sequence, ie proximal to distal or lower body before upper body. In other words, the ‘loading’ is quite useless for all those who come over-the-top (often as a direct result of the loading process itself!)
PP4: Momentum. This term, in physics, means ‘quantity of motion’. It is a product of the mass of an object and its velocity. As velocity changes with the direction of motion, the momentum of the golf club is zero at the top of the backswing, and must be recreated during the downswing, so momentum is not an appropriate term to use here. For the same reason, neither are velocity or acceleration.
PP5: Creating time/space for acceleration to take place. In many sports a person is told to increase the length of their swing/motion so as to give themselves a greater distance over which to accelerate. To my mind it means exactly the same as telling someone that driving from New York to California will allow them to accelerate more than merely driving to New Jersey! If distance increases without time reducing, velocity and thus acceleration do not automatically increase. Moreover, in the case of human muscle, can muscles hold their forceful contractions as efficiently over longer distances? After all, it is well-known that muscle force and velocity are inversely related.
PP6: Leverage. A wider arc creates a longer lever so that more force can be created with less effort. Yet, when a golf swing goes ‘on-and-on’ with a lot of wrist ‘cock’, where is the wide arc? Merely having a wide arc at the start of the backswing but narrowing it down considerably by bending the trail elbow and wrist no longer count as ‘wide’.
So, what then, IS the purpose of the backswing, if nothing above can be converted to useful positions or forces (to give both distance AND direction) during the downswing? I have no idea!
I only know the purpose of the Minimalist Golf Swing’s backswing – to place all the body’s joints into positions that harness maximal external force, thus reducing the effort required by the golfer’s muscles; and for an inside path. To me, most other backswings make no sense in science!