I love to use the three dimensional models when talking about the pelvis. It makes it so much easier to visualise what is happening in this remarkable area of the body.
Sitting is the perfect opportunity to experience the support capacity of the pelvis. Try it two ways.
1/ tail tucked under, weight behind sitbones (image).
2/ tail reaching back, weight in front of sitbones and into thighs (image)
How do you feel? How easy is it to achieve uprightness? How is your breathing? How about your perspective on the world?
This gif shows the movement and the anatomy. Notice the tail and sit bones moving back and how this changes the spine curves from a C to a soft S curve. Very often when we try to correct our posture we lift our chest up and pull our shoulders back but we don’t do anything to change the pelvis. It takes a lot of effort to hold this position. But if we change the pelvic orientation the chest naturally rises and the shoulders sit more easily into the back space.
In the next video we can see my pelvis model sitting on a meditation cushion. The tail in not taking any weight. The bones on the cushion are called the rami. They connect the sit bones to the pubic bone and are part of the pelvic floor (I’ve written more on the pelvic floor here). We can see the tail is a far more delicate structure that the rami. It is not designed to hold the weight of our body!
When I sit on the tram and notice people sitting there appears to be a kind of nonchalant attitude linked with the tail tucked under sitting. Coolness, safety and life in the device. I wonder if we were still spending time squatting each day whether we would be sitting this way so much. Luckily many of us are changing these habits and intentionally reclaiming healthy movements in our life. The child below reminds us that we are not born with tails tucked under. We are born free to squat and live with an upright spine and a delight in life.