Flexor muscles are a group of muscles that enable bending movements at joints. They work by contracting to decrease the angle between two body parts, such as the elbow or knee. Common examples include the biceps brachii in the arm and the hamstrings in the leg. These muscles are essential for various daily activities, such as lifting objects, walking, and sitting. Flexor muscles are often paired with extensor muscles, which perform the opposite function by straightening joints. Together, they help maintain balance and coordination in movement.