What does flexion refer to in muscular actions?

Flexion refers to the action of bending a limb or joint, resulting in a decrease in the angle between two parts of the body. This movement typically occurs at joints such as the elbow or knee, where the body parts come closer together. For instance, when you bend your arm at the elbow, you are performing flexion, as the angle between your forearm and upper arm decreases.

In contrast, straightening a limb would be described as extension, turning a limb would involve rotation, and stretching of muscles generally refers to elongating the muscle fibers, which is different from the action of flexion. Understanding muscular actions is crucial in fields such as anatomy, physical therapy, and fitness, as it helps professionals analyze and improve movement patterns and physical function.