Yoga Anatomy: The Rectus Femoris Muscle in Yoga
In this blog post we examine the rectus femoris muscle and its relation to yoga poses, beginning with an overview of the muscle and how it stretches. We conclude with some interesting synergy that can occur between the rectus femoris and the gluteus maximus in poses where both the hip and knee are extending, such as Warrior I.
Here’s the anatomy…
Yoga Anatomy: The Rectus Femoris
The rectus femoris is one of the four heads of the quadriceps muscle. It runs from the anterior inferior iliac spine to the quadriceps tendon, which attaches to the patella or knee cap. The patella then attaches to the tibial tubercle via the patellar tendon. The rectus femoris thus crosses both the hip and the knee, making it a bi-articular muscle. Note that the other three heads of the quadriceps muscle only cross the knee joint and are mono-articular (figure 1).
The rectus femoris combines with the rest of the quadriceps to extend the knee joint. It also acts as a synergist of hip flexion and has increased activity with abduction and external rotation of the hip joint. Figure 2 illustrates this in Supta Padangustasana (performed with the leg abducted). Learn more about the relationship between the quadriceps and the pelvis in our blog post, “Preventative Strategies for Lower Back Strains in Yoga.”
How to Stretch the Rectus Femoris with Yoga
Stretching the rectus femoris is best accomplished in yoga poses that combine hip extension and knee flexion. Poses like Virasana (with the hips flexing) are good for stretching the other heads of the quadriceps, however, a reclining variation is necessary to lengthen the rectus femoris. Figure 3 illustrates two poses that stretch this muscle.
Finally, figure 4 illustrates the “antagonist/synergist” relationship between the rectus femoris and the gluteus maximus in poses like Warrior I. The gluteus maximus is a hip extensor and, thus, an antagonist of the rectus femoris for this action. If the foot is fixed on the mat, contracting the gluteus maximus tilts the pelvis as shown (closed chain action). Tilting the pelvis back and down creates a pull on the rectus femoris, which is transmitted to the knee joint, leading to more efficient knee extension. In this manner, the gluteus maximus is an indirect synergist of knee extension.
Printed with permission from TheDailyBandha.com
Author, Ray Long MD FRCSC is a board certified orthopedic surgeon and the founder of Bandha Yoga. Ray graduated from The University of Michigan Medical School with post-graduate training at Cornell University, McGill University, The University of Montreal and Florida Orthopedic Institute. He has studied hatha yoga for over twenty years, training extensively with B.K.S. Iyengar and other leading yoga masters.
3d Graphic Designer / Illustrator Chris Macivor has been involved in the field of digital content creation for well over ten years. He is a graduate of Etobicoke School of the Arts, Sheridan College and Seneca College. Chris considers himself to be equally artististic and technical in nature. As such his work has spanned many genres from film and television to videogames and underwater imagery.