Inversion Helps Provide Care and Feeding for the Discs
Your discs have three jobs: to separate the vertebrae, provide flexibility to
the spine and to act as shock absorbers. Disc separation is especially important
since all communication between the brain and the body is via nerves that pass
between each vertebra. Insufficient distance between the vertebrae can result in
nerve root pressure and pain.
The
inner core of your discs is made of jelly-like material that provides the
flexibility and "cushioning" in your back. When you are sitting,
standing, or exercising, which I'll term "weight-bearing activities",
fluid is squeezed out of your discs and into adjacent soft tissue (just as you
would squeeze moisture out of a sponge). As a result, your discs lose some of
their moisture and height. To prove this fact, measure yourself in the morning
and then again at night. You will lose 1/2" to 3/4" in height by the
end of the day. This lost fluid translates into your discs loosing some of their
cushioning effect.
When you are sleeping, "a non-weight bearing activity", your discs
(or "intravertebral sponges") expand as they soak up fluid and
nutrients and increase the length of your spine by as much as 3/4". But you
don't gain the full height back, accumulating to a total of 1/2" to 2"
in height throughout your lifetime.
When your discs are compressed and thinned, your vertebrae potentially place
more pressure on these nerve roots. More pressure equals more pain. As you
relax, your spine begins to stretch. The space between each vertebra will
increase, thus decreasing the pressure on the discs between each vertebra. This
encourages fluid movement back into the disc, helping to keep your discs plump
and happy and decreasing the pain in your back.
In fact, the only time in your life when you are giving your discs a break is
when you are inverting. See graph. The medical study that generated this graph
measured the pressure inside the 3rd lumbar disc-it was assigned a baseline
pressure while standing of 100%. The study reported that even when you are lying
down, the disc pressure remained at 25%. The hundreds of ligaments and muscles
that encase and mobilize the spine act like a bunch of rubber bands holding the
spine in compression equal to 25% of standing body weight. Inverting to 60° is
necessary to reduce the disc pressure to zero. Inverting is the most effective
posture that allows your discs to recover from the constant pressure placed on
them during your daily activities.
