Kinetic Chain

The kinetic chain describes how bones, joints and muscles connect so that motion or force at one segment influences the others. In a tennis serve, energy generated in the legs and hips is passed up through the trunk and out through the arm; in a football kick the same energy passes through the trunk and out through the swinging leg and foot. In each case the links add to the final speed in a sequence often called the summation of forces.

Coaches distinguish open-chain movements, where the end segment such as the hand or foot moves freely, from closed-chain movements, where it is fixed against a surface as in a squat or push-up. Understanding the chain helps explain why efficient technique relies on coordinated timing across the whole body rather than isolated strength.