1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

5 Body Parts You Didn't Know You Had

The Intercostals, Sit Bones, Sacrum, Psoas, and Piriformis

By

Updated October 21, 2013

Do you know your piriformis from your psoas? If you do, you are probably really into yoga, because yoga introduces you to body parts you never knew you had. And once you know about them, you better believe you are going to stretch them out. 

1. The Sit Bones

Sit Bones
By D.renard, svg by MichaelFrey from Wikimedia Commons

You may hear them called sits bones or sitting bones, but chances are you never heard of them at all (much less the ischial tuberosity, their anatomical name) until your yoga teacher told you to sit on them.

2. The Sacrum

Courtesy ADAM

Did you know there is a triangular bone at the base of your spine, right above your tailbone? Well, that's the sacrum and it comes up a lot in poses where you are lying on your back. Ok, actually, it should usually stay down in poses where you are lying on your back.

3. The Psoas

Psoas and Hip Flexors
By Beth ohara via Wikimedia Commons
The psoas major (and yes, there is also a psoas minor) may be yoga's most mysterious muscle. Located deep in the core, this muscle is tremendously important while being very hard to identify. Strengthening and lengthening the psoas is key for anyone suffering from back pain due to sitting too much, so check out these poses for the psoas if you are a desk jockey.

4. The Piriformis

Piriformis Muscle
Gray's Anatomy, via Wikimedia Commons
Running right behind the psoas (figuratively, and somewhat literally) for the title of least famous muscle is the piriformis. Stretching this little muscle in your butt can have a big impact if you suffer from sciatica.

5. The Intercostals

Intercostal Muscles
Gray's Anatomy, via Wikimedia Commons

Ever feel sore around your ribs after a lot of back bending or twisting? That's your intercostals talking. These muscles are also responsible for the expansion and contraction of your rib cage when you breath.

  1. About.com
  2. Health
  3. Yoga
  4. Yoga and Your Health
  5. Anatomy
  6. 5 Body Parts You Didn't Know You Had

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.