The term kinetic chain is often used when describing movements of the body. It is usually used to describe body movements responsible for generating power in the body. More specifically, it refers to the potential energy available from each joint action or body part movement.
When adjacent joint actions occur in sequence, with a slight overlap from the ending of one movement to the beginning of another, you get a transfer of the energy generated in the one movement to the next adjacent joint movement. The more sequential joint actions you get involved, the more force that you can generate.
In essence, as you get more joint actions involved in a sequential manner from one joint to the other, you get a maximum summation of force that is released in the last joint action. For example, a pitchers buildup of force begins with the stride in which the hips are pushed forward and ends with the wrist and finger action in the release of the ball.
Since the major force producing actions in the body are the hips and shoulders you can generate tremendous force by executing three movements in sequence. They are: weight shift in which you shift your hips to the front leg followed by hip rotation and then shoulder rotation. In these three actions you generate the greatest amount of force in comparison to arm, elbow and wrist actions.
The kinetic chain however, also involves arm, elbow and wrist actions depending upon the action being executed. This includes almost all kinetic chain actions seen in effective throwing, hitting, jumping and kicking actions.
For more information see Build a Better Athlete