The iliopsoas or hip flexors are a grouping of two muscle groups, your iliacus and your psoas major and minor. The psoas major stretches from the middle of your spinal cord to the top of your thigh bone and it is the only muscle that directly connects your legs to your spine. It is responsible for moving your thighs up toward your torso and is thus important in physical activities such as walking, running, standing or cycling. Additionally, the psoas helps promote good posture by stabilizing your back, pelvis and midsection.
You may suffer from tightness in the psoas if you lead a sedentary lifestyle and spend too much time sitting down, as this shortens the muscle. Tightness may also occur if you are a long-distance runner or cyclist, as you contract the muscle every time you lift your leg, which may lead to overuse. A tight psoas can cause postural problems such as an arched lower back, a hunched back or an anterior pelvic tilt. These can lead to lower back, hip and groin pain.
Leg lifts are simple calisthenic exercises that require you to repeatedly lift your leg or legs in a set direction. They can be done while lying on your back, lying on your side, seated or while standing. Regardless of which variation you use, you will be targeting your iliopsoas muscles when you perform this exercise. Leg lifts require your psoas to contract and lengthen, which loosens up the muscle and decreases the chance of tightness or injury.
Lie flat on your back on a bench or the floor. Place your hands under your backside with your palms facing the floor to support your pelvis. Keep your feet together for the duration of the exercise. With your legs fully extended, lift them until your feet are 1 to 2 feet off the floor. Hold that position briefly and then return your feet to their starting position. Repeat as necessary. You can also bring your knees up to your chest to fully contract the psoas.
Tightness in the psoas results from years of bad habits, so correcting this can take some time. Stand up as often as you can, and try to avoid long stretches of sitting down. When you do sit, maintain proper posture without hunching or arching your lower back.