The hip flexor is a crucial part of human functioning in everyday life. From basic activities like walking, standing up and sitting down, to physically demanding activities like sports and weight training, it is involved more than you might know.
What does the Hip Flexor do? It has both major and minor functions, and is able to fulfill different roles because it is composed of several muscles, the largest ones are discussed below. The primary goal is to facilitate flexion of the hip joint. In normal terms, this means that the hip flexor is used anytime the knee is lifted up, a step is taken, or a stair is climbed. The muscle group also has those smaller muscles whose purposes are mainly stabilization roles, so when you lift up your knee on an angle, these muscles provide the power needed in the lateral(horizontal) direction.
Anatomy | Location?
Everyone knows all about the hamstring, the quad, the groin, but the hip flexor gets far less exposure, even though it is just as important as any other muscle in your body. It is actually a muscle group located towards the front of your leg/abdomen; it is composed of smaller, but sizeable muscles as shown in the picture. When looking at what they do, we must examine the role that the Psoas and Iliacus play in movement; these are the two main muscles in the Iliopsoas, which is by far the largest and most important muscle group.
The Psoas: The Psoas muscle is actually divided into 2 distinct sub-muscles: Psoas major and Psoas minor. The Psoas major is the larger muscle that connects the pelvis to the lumbar region, as shown in the picture and is one of the major muscles at risk for an injury. The Psoas minor on the other hand is a muscle located slightly in front of the Psoas major in the muscle group; however, it is important to note that only about half of humans have this muscle! The minor muscle supports the same role that the Psoas major plays, which is to facilitate flexion of the hip joint. If you have recurrent pain in the psoas area, you might want to read about hip tendonitis.
The Iliacus: The Iliacus is that small triangle shaped muscle shown in the picture, its role is to assist with movement, but mainly it functions by connecting the hip bone to the Psoas major. This is considered a secondary muscle for hip flexion and is rarely injured compared to the Psoas.