What Is An Oblique Muscle?

You may have tried to work your obliques before with specific core exercises, but what exactly are the obliques? What do they do?

There are actually two different oblique muscles on each side of your body — the external oblique and the internal oblique. They are layered with the internal oblique underneath the external oblique, and there is a third muscle underneath those called the transversus abdominis muscle. So, your external oblique is closest to your skin, then the internal oblique, and then the transversus abdominis muscle. These three layers make up the muscles on your sides. 

The internal oblique runs from the bottom of your ribs to your pelvis, and your external oblique is larger, running from your chest to the top sides of your pelvis. Oblique muscles help you move when you bend sideways, twist your trunk, and contract slightly when you walk. The obliques are also important for breathing. Try forcing an exhale, and you'll feel those muscles on your sides contract. 

Your obliques help support the spine, protect your organs, and even help when you cough, sneeze, urinate, pass stool, and give birth. These muscles are essential for so many functions, so learning how to strengthen them will help them help you (via MedicineNet, Biology Dictionary, and Healthline).  

Start with some beginner bodyweight exercises and take it slow. Stop if you feel any pain to avoid injury. Injuring the obliques can be debilitating, as they are important for many bodily functions. 

Start with the bird dog. Begin on all fours with your knees and hands hip-width apart. Reach forward with your right arm and gently move your left leg straight back at the same time. Pause for a few seconds, and then bring them back in and return to the starting position. Repeat on the opposite sides with your left arm and right leg. Keep your trunk from chest to hips in the same position throughout the exercise. 

Next up is side planks. Lie on your right side with legs straight and prop up your body on your right forearm, so your fist is facing forward. Place your left hand on your hip while the outer side of your right foot is on the floor. Hold for up to 30 seconds and repeat on the other side. 

Crossbody mountain climbers will also strengthen those obliques. Go slower than you would traditional mountain climbers. Start in a standard pushup position with your upper feet and hands holding you up. Your wrists need to be in line with your shoulders. Bring your right knee toward your left elbow and repeat on the other side (via Healthline and Men's Health).