When talking about stretching the hip flexors, the psoas major and minor muscles get most of the attention, putting the iliacus in the shadows. However, the iliacus plays a major role in hip flexion, hip extension and hip lateral rotation. You cannot feel this muscle because it is deep in your pelvis, extending from the iliac fossa at the curving crest of the pelvis to the lessor trochanter of the thigh bone, which is a small bony protuberance in the back and upper part of your femur. Every time you stretch your hip flexors, you are also stretching the iliacus.
Use this active stretch to warm up your hip flexors before you work out. This exercise flexes and extends your hip and knee joints while working on core stabilization. Kneel on the floor on your hands and knees with your hands below your shoulders and your knees below your hip joints. As you extend your right leg behind you, do not move your spine. Hold this position for two seconds. Then bring your right knee toward your chest gradually with no or minimal flexion of your lower spine. Return to the starting position. Do 10 reps on each leg.
Stretching your hip flexors in different directions loosens the muscle fibers and fasciae that can get shortened from sitting too much. Kneel on the floor on your right knee and put your left foot about 1 foot in front of you with your knee bent at about 90 degrees. Raise your right arm over your head, and shift your weight to your left foot. You should feel a stretch in your psoas and iliacus. After you hold the stretch for three deep breaths, lean your torso to your left, stretching your hip flexors laterally. Hold the stretch for three deep breaths. Repeat the stretch on each side two to three times.
Dynamic stretching integrates your hip flexors with other muscle groups to function together as one unit, improving your blood flow, neural communication between your muscles and your brain and balance. One such exercise is the ginga, which is a Brazilian capoeira footwork that emphasizes hip and leg extension as you move side-to-side rhythmically. Stand with your feet slightly apart, and step back with your left leg about 2 feet behind you, shifting your weight on your toes and the ball of your right foot. Keep both legs slightly bent. Then step your right foot forward to the starting position and step back with your left leg, shifting your weight in the same manner. Repeat the pattern for one to two minutes, building your own speed and rhythm. Never hunch your shoulders or back as you move.
If you experience pain as you move or stretch or if you hear or feel your hip joint making a clicking sound when you move, check with your health care provider before you continue to train. Inflammation of the iliopsoas tendon can be the cause of this, which is caused by the tendon rubbing over the bone of the hip joint.