The obturator externus is a small, deep muscle in your hip. It sits underneath your larger glute muscles and is positioned on the outside of your pelvis, close to where your thigh bone meets your hip socket. Even though it is not visible from the outside and it is not an “ab muscle,” it plays an important role in how your hips move and how stable your pelvis is during training.
Its main job is to rotate your thigh outward, meaning it helps turn your knee and foot slightly away from your body when your hip is extended or in neutral. It also helps keep the head of your thigh bone centered in the hip socket, especially when you are standing on one leg, walking, running, squatting, lunging, or changing direction. Think of it as a “hip joint stabilizer” that quietly keeps your movement clean and efficient.
Why should you care if your goal is visible six pack abs? Because your core does not work in isolation. If your deep hip stabilizers are weak, tight, or not coordinating well, your pelvis can tilt or shift during leg training, sprinting, and loaded carries. That can reduce glute engagement, change your squat and hinge mechanics, and sometimes contribute to hip pinching, groin discomfort, or lower back overwork. When your hips are stable, you can brace better, transfer force more efficiently, and train harder with less irritation, which supports the consistent training and calorie burn that make abs show.
You typically feel the obturator externus working during controlled hip rotation drills, single leg balance work, and well executed lower body lifts where your knees track smoothly and your hips stay level.