If you visit the gym regularly and focus on strengthening your core, it's more than likely that the ab roller wheel is your arch nemesis. Despite its innocent appearance, the ab roller wreaks havoc on your core muscles and makes you want to scream, "No more!" Although most people associate this device with building their abs, it mainly targets the iliopsoas.
To correctly use the ab roller wheel, which is more commonly known as an ab wheel or ab roller, hold the device's handles and kneel on the floor. Bend at the hips and lean forward to shift your weight onto the wheel, which you should hold a few inches in front of your knees. Keeping your arms straight, push the wheel away from your body as far you can and then pull the wheel back toward your knees to complete one rep.
Though using the ab wheel requires the use of several muscle groups, it primarily targets your iliopsoas muscles, which are found deep in your hips. This muscle is made up of two parts named the iliacus and psoas. The common term for this muscle is your hip flexor and, as its name indicates, you use this muscle during flexion of your hip.
Although your core muscles aren't the target of a correctly executed ab wheel rollout, they're considered stabilizing muscles during this exercise. During an exercise, the stabilizing muscles contract but don't otherwise move when you hold a posture. The rectus abdominis and oblique muscles, which are found in your lower abdomen and sides of your torso, respectively, contract to stabilize your torso while you push the ab wheel away from your knees and pull it back toward you.
When you execute an ab wheel rollout, several muscles act as synergists. During an exercise, a muscle that works as a synergist helps another muscle during the movement. When using the ab wheel, synergists include a number of muscles in your legs, such as the sartorius and adductors. Other synergist muscles include your latissimus dorsi, pectoralis and rhomboids, which are located in your torso, chest and upper back, respectively.