Studies which observed CSF flow during breathing found that the inward breath elicited a high movement of CSF whereas holding the breath suppressed it. As we breathe in, the spine performs a subtle rocking movement. The diaphragm pushes downwards onto the sacrum and causes it to form a more pronounced lumbar lordosis (minor swaying of the back) which activates the sacral pump and as we fill up into the upper lungs our sternum rises and the head draws slightly back activating the cranial pump. As we breathe out the opposite happens. So our spine is continually pulsating back and forth with the inward and outward breath and as it pulsates the CSF is encouraged in its journey up the spine into the brain and back down again.
The deeper our breath the more efficient our pumping system will be. Many people are shallow breathers, which tends to make us feel sluggish and can have a mild effect on the brain. Complete yoga breathing teaches us to breathe deep down into a relaxed abdomen and fill up into the top of the lungs and then empty from the top to the bottom finishing with a squeeze of the abdomen. A more pronounced effect can be produced with what is known as Bhastrika Pranayama (Bellows Breath) which emphasizes a strong and often fast inward and outward breath and it is postulated that this creates a stronger movement of the CSF.
According to Dr. Don Glassey, Alternate Nostril Breathing increases pressure in one nasal cavity after another which is said to initiate the cranial pump
Brahmari Pranayama or Humming Bee Breath is a wonderfully calming breath that reverberates into the sinuses and bones of the head and increases Nitric Oxide levels. Nitric Oxide, amongst other wonderful outcomes, assists in the drainage of lymph from the brain.
While the whole spectrum of yoga asanas is beneficial for the flow of lymph throughout the body one of the best asanas specific to the movement of CSF is the simple Cat/Cow Flow. In this pose the spine is alternately flexed and extended from the sacrum up to the base of the skull, in time with the inward and outward breath, enhancing the flow of CSF. The traditional favorite of every yoga sequence, Surya Namaskara, Salute to the Sun, has a similar pumping action.
When you have experienced a severe emotional trauma or stress (especially repeated stress), the body becomes overly acidic. When the lymph in which each cell rests becomes acidic the nutrients cannot successfully pass through the cell membranes and the wastes have difficulty passing back out. This causes the lymphatic system to congest causing acidic cellular waste to build in the body, cerebrospinal fluid and brain. To deal with this acidic environment we need to have a multi-pronged approach, taking into consideration the diet, an easy fitness regime, exercise, breathing, relaxation and meditation.