(Summary of the “addressing the ball” stance)
1. Bend forward from the waist.
2. The back must be straight with the head held up.
3. The backside should protrude to the rear.
4. The arms must be held clear of the chest.
5. The knees must be flexed.
Backswing;
The next stage of the preparation stage is the backswing, this is when the performer initiates the swing by moving the golf club head away from behind the golf ball, usually to above the height of the shoulders. The sole purpose of the backswing is to correctly position the club at the top of the swing in preparation for the downswing into the ball and along the intended line of flight. The swing is started primarily by a backward movement of the left hand and arm in order to move the golf club away from the ball. Friction is again in play at this moment, but where with the stance, it was static friction, the backswing involves dynamic friction. This type of friction deals with keeping a good grip with the ground whilst the feet and body are in motion. Friction is also an important factor when it comes to the point of contact of the performer’s hands and the golf club. Golf clubs normally have a rubber or leather grip on them to help keep a hold of the club throughout the swing, however in addition to this most golfers choose to wear a thin leather glove in order to improve there grip even more. The glove is worn on the left hand, (if right handed), as it is the left hand that has the main control over the club, and is holding the club tightest, so it is this hand that requires more friction on the clubs grip.
Muscular force is now needed in order to move the club away from the ball, first in the hands and arms then shoulders then hips are involved in an upper body rotation movement, as the club moves higher the shoulder rotates until the left shoulder is pointing in the direction of the ball. There are a couple of things working against this muscular force, they come in the form of gravity and air resistance. As the muscles work to lift the club away from the ball, gravity is working to force both the club and the arms back down the way, and at the same time air resistance is also working against the swing. These two factors are minimal due to the light weight materials such as carbon fibre that is used to make golf clubs.
At the start of the preparation stage, i.e. addressing the ball, the body’s centre of gravity runs down the middle. As the club is moved away from the ball and the upper body starts to rotate a transfer of weight begins. Where at the beginning the weight was distributed evenly on each foot, it now changes to 60% on the right foot and 40% on the left, at the same time the body’s centre of gravity moves to right of centre. A good way to think of the body’s centre of gravity in relation to the golf swing is to think of it moving to which ever side of the swing the hands are on at the time. So when the hands are central then so is the centre of gravity and likewise for when the hands are either to the left or right of the body.
Right at the very top of the swing, just at the stage where the club changes from going up to going down to hit the ball, is the precise moment that inertia takes place. Inertia is when an object is temporarily suspended and all acting forces cancel themselves out.
(ACTION)
The action stage begins from the moment the golf club changes from being the backswing into being the down swing, the club then travels downwards at the desired speed to connect with the ball. As soon as the ball leaves the face of the golf club, this is then the point when the action stage is over.
Downswing;
Transition from backswing to downswing is the slowest phase of the swing, however it is just after the point of inertia that the performer needs to generate the most power in order to hit the ball the desired distance to reach its target. Because the performer is going from a slow movement to a fast in a split second, a good grip is needed on the surface to achieve maximum power in the swing. This is yet another part of the swing where dynamic friction is involved; both where the golfer is holding the clubs grip and, where their feet come in contact with the ground, the feet move during this part of the swing that is why as soon as the feet move it changes from static to dynamic friction.
Muscular force plays a big part at this stage of the swing, it is during the action phase that the power is generated. The power is produced through mainly upper body muscles, shoulders, arms and hands for example, but also the abdominal muscles and legs are also in use to generate this power. The lower body muscles initiate the power by moving the hips out of the way so as to allow the hands and arms to swing through the ball freely.
Air resistance and drag are factors which can affect the swing within the action phase. On the downswing, the club is moving at its fastest, it therefore has greater air resistance than at any other time during the swing.
The drag is created just before the impact of the club and the ball, the club may just skim the surface or even go deep enough into the ground to create a divot, if this happens, this is when drag comes into effect.
Depending on where the club face connects with the ball, determines how much spin will be on the ball. If for example the club hits the ball near the bottom, then this will make the ball spin backwards after it has left the face of the club, likewise if the club hits the top, left or right of the ball, this will affect the spin of the ball.
