What does the term extension refer to in the context of joint movement?

The term extension in the context of joint movement specifically refers to the action of straightening a joint, which increases the angle between the bones that make up the joint. For instance, when you extend your arm at the elbow, you move from a bent position (flexion) to a straightened position, effectively increasing the angle between the forearm and the upper arm. This movement is essential in various physical activities as it allows for a full range of motion and contributes to functional movement patterns. Understanding extension is crucial for fitness professionals, as it helps them guide clients through exercises that properly utilize joint movements while maintaining safety and effectiveness.