Golf stroke mechanics is the means by which golfers make decisions (selecting clubs, selecting shots) and execute them (making shots) in the sport of golf. For all golfers, it consists of a pre-stroke, in which golfers choose which club they want and their stance, and the actual stroke. The stroke is a complex motion and there is still disagreement on what constitutes a "good" golf swing. In Work and Power Analysis of the Golf Swing, Nesbit and Serrano suggest the golf swing has been studied by scientists and mathematicians who have developed various equations to help explain the complexity of the swing. It is generally agreed that a successful and consistent golf swing requires precise timing and mechanics, from the grip and position of one's fingers, to the position and movement of the feet. At any moment of the swing, whether back-swing, downswing, or upswing, something can go wrong that will throw off the whole body and result in a mishit.
The goal of the golf swing is to direct as much kinetic energy as possible into the club head so when it comes into contact with the ball, all of the energy will transfer to the ball, sending it into flight. The complex motion of the body first starts with the stance. This is critical to make sure the golfer has a low center of gravity to remain balanced throughout the swing path. The swing starts with the arms moving back in a straight line. When the club head reaches the level of the hip, two things happen: there is a stern wrist cock that acts as a hinge along with the left knee (for a right handed swing), building up its torque by moving into the same line as the belly button before the start of the upswing. As the swing continues to the top of the backswing (again for right-handed golf swing), the golfer's left arm should be perfectly straight and his right arm should be hinged at the elbow. The downswing begins with the hips and the lower body rather than the arms and upper body, with emphasis on the wrist cock. As the golfer's hips turn into the shot, the right elbow will drop straight down, hugging the right side of the golfer's torso. As the right elbow drops, the wrists begin to snap through from the wrist cock in the backswing. A solid extension of the arms and good transfer of body should put the golfer leaning up on his right toe, balanced, with the golf club resting on the back of the golfers neck. Importantly, all of the movements occur with precise timing, while the head remains completely still with eyes focused on the ball throughout the entire swing.
A golf stroke uses muscles on core (especially erector spinae muscles and latissimus dorsi muscle when turning), hamstring, shoulder and wrist. Stronger muscles on wrist can prevent wrists from being twisted at swings, while stronger shoulders increase the turning force. Weak wrists can also deliver the impacts to elbows and even neck and lead to injury of them. (When a muscle contracts, it pulls equally from both ends and, in order to have movement at only one end of the muscle, other muscles must come into play to stabilize the bone to which the other end of the muscle is attached.) Golf is a unilateral exercise that can break body balances, requiring exercises to keep the balance in muscles. A recommended exercise is free weight, an exercise not reliant on machines to stimulate and balance the fine muscles.