What is the action called when the angle between two body parts decreases, such as bending a limb?

The action in which the angle between two body parts decreases is known as flexion. This occurs when a joint is bent, bringing two bones closer together. For example, when you bend your elbow or knee, you are performing flexion at those joints. This movement is essential for many daily activities, such as sitting down, picking up objects, and walking.

Understanding flexion is critical in health science because it highlights the ways muscles and joints work together in the body. The opposing action of flexion is extension, which involves straightening a limb or increasing the angle between body parts. This distinction is important for comprehending human movement and for various rehabilitation practices, where strengthening or improving flexibility of muscles involved in these actions may be necessary.