What is defined as the decreasing of the joint angle or bringing two body segments closer together?

Flexion is defined as the action of decreasing the angle between two body segments or bringing them closer together, which typically occurs at a joint. For example, when you bend your elbow or knee, you are performing flexion by reducing the angle formed at those joints. This movement contrasts with extension, where the angle increases, and the segments move farther apart.

In the case of muscle movements, flexion is usually associated with the contraction of muscle groups that bring limbs or body parts closer to the torso. It is an essential concept in understanding basic human movement and biomechanics, and it is commonly referenced in various fitness regimes and physical activities to assess how joints function during exercises.