It’s tIme for another Essentrics with Amanda “Back to Basics” post. This month, let’s talk about working the quad/psoas muscle grouping correctly. Let’s start with the quads.
The quadriceps femoris is in fact a group of 4 muscles that are responsible for extending the knee and leg: rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis. Of these, the rectus femoris also flexes the hip joint.
What is commonly called the psoas is actually the iliopsoas. It is comprised of two muscles - the iliacus and the psoas major - that flex the hip joint and the lumbar vertebrae, aka, the lower back.
Weak quad muscles can result in knee pain, while a weak iliopsoas plays a role in low back pain. (1) Check out these descriptions from The Anatomy Coloring Book:
“the tendons of iliacus and psoas major converge to a single insertion (iliopsoas). Iliopsoas, a strong flexor of the hip joint, is a powerful flexor of the lumbar vertebrae; a weak psoas may contribute to low back pain.” (p. 42)
“Rectus femoris is a strong hip joint flexor, and is the only member of quadriceps to cross that joint. Quadriceps femoris is the only knee extensor. The significance of its role becomes crystal clear to those having experienced a knee injury; the muscles tend to atrophy and weaken rapidly with disuse, and “quad” exercises are essential to maintain structural stability of the joint.” (p. 56)
The quad and psoas are important muscles to walking and running, which is why it is vital to maintain their flexibility and strength. While you may not be a runner, you are most certainly in need of these muscles for walking. (2)
Many participants have difficulty with the Essentrics standing quad/psoas sequence. I will often hear someone chime in, “I don’t feel anything,” or, “I’m not feeling it there, I’m feeling it in my calf.” When they demonstrate the movement for me after class, I see the problem immediately - incorrect alignment. Body awareness and alignment are fundamental principles of Essentrics that are inextricably linked: “A major part of injury prevention is awareness, the link between the mind and the body. Awareness in ESSENTRICS is the conscious and deliberate alignment of all joints: knees, hips, and spine. Awareness is being sensitive to when a movement feels wrong, feels awkward or is putting an unhealthy strain on muscles. The more aware you are, the better any movement is performed, and the better the results will be.” (3)
Take a moment to watch this video about the quad/psoas sequence. Then replay the video while you try it yourself. Try to position yourself in front of a mirror and watch for “popping up” in your body. Do you feel the difference? If not, watch the video again. Trust me - once you feel the difference in your body, you will have an easier time with alignment during class.
Let's make sure you avoid back and knee pain and potential injuries by stretching the proper muscles - i.e., the quad and psoas muscle groups. You'll thank me later.
Amanda Sterczyk is an international author, Certified Personal Trainer (ACSM), an Exercise is Medicine Canada (EIMC) Fitness Professional, and a Certified Essentrics® Instructor.