"외비복근" refers to the external oblique muscles, which are located on the sides of the abdomen. These muscles play a crucial role in trunk rotation and lateral flexion, allowing the body to bend and twist. They also help stabilize the core during various movements. Strengthening the 외비복근 can improve overall athletic performance and posture. Exercises such as side planks and Russian twists specifically target these muscles. A well-developed core, including the 외비복근, contributes to better balance and reduces the risk of injury during physical activities.