Benefits of Yoga: A youthful spine

camel pose: ustrasana

"You're only as young as your spine is flexible." I'm not sure who said this, but it makes sense when you think about how much we rely on our backbone. Our spine is flexing and contracting with almost every move we make.

According to CBS News, eight out of ten Americans will experience debilitating back pain sometime in their lives. Additionally, more than 1.2 million Americans undergo spinal surgery each year. That's more than TRIPLE the number of coronary by-pass surgeries (415,000), and nearly FOUR TIMES the number of hip replacements (327,000).

The most common culprit of back pain, is believed to be related to the gelatinous disks which cushion the vertebrae.  "I think most people would think it's the inter-vertebral discs, whether it's herniated or whether it's just worn and arthritic and associated with pain," said Dr. Augustus White, a professor at Harvard Medical School.

In the adult body, these inter-vertebral discs have no blood supply of their own, but instead rely on nearby vessels to nourish them. With normal aging, the limited supply of blood flow diminishes and the discs gradually dry out and become thinner. Dry and thin discs become rigid, causing in pain and injury along the spine.

Enter Yoga. Yoga has long claimed that all its bendy, stretchy, and twisty poses are good for your spine.  In  2011, a scientific study examined such declarations and found that yoga can, in fact, counteract deterioration of inter-vertebral discs. The 2011 study involved a group of 36 participants, who were each examined by a team of physicians in Taiwan. "Half [of the participants] had taught Hatha yoga for at least 10 years, and the other half were judged to have exhibited good health. The two groups showed no statistical difference by age or sex. The physicians then scanned all the spines and carefully inspected the discs for signs of damage. The results, the team wrote, showed that yoga teachers had 'significantly less' degenerative disease then the control group."

"Why? The physicians suggested that spinal flexing may have caused more nutrients to diffuse into the disks. Another possibility, they wrote, was that the repeated tension and compression of the disks stimulated the production of growth factors that limited aging" (Broad, 41).

Science is beginning to catch up to what yogi's have known for years.

References:

Chin-Ming Jeng, Tzu-Chieh Cheng, Ching-Huei Kung, et al., "Yoga and Disc Degenerative Disease in Cervical and Lumbar Spine: An MR Imaging-based Case Control Study," European Spine Journal, vol. 20, no. 3 (March 2011), pp. 408-13.

Broad, William J. (2012) The Science of Yoga. New York, NY: Simon & Shuster.

Photo credit: Lauren

Benefits of yoga: Enhanced Immune Function

I was a biology major in college and human physiology and research are of particular interest to me (especially when it relates to yoga and the need for yoga clothing). Yogis often describe body function in terms of energy movement though invisible wheels and channels called chakras and nadis. While I believe these have been very useful metaphors of the body for thousands of years, now that we have modern research, I think we can speak in terms of their physical counterparts.

I began my yoga practice in November of 2009. Recently, as I have been reflecting on my three years of practice, I have noticed that haven't felt sick.. in quite awhile. The last time I can remember being sick, was having the flu in the summer of 2009. So, coincidentally? in time that I have been doing yoga, I have not felt ill. No colds, no flu, nothing, except for some spring time allergies, which I've taken less and less allergy medicine for each year. This year I think I only took Zertek for about a week in April.

Since at least 2007, medical scientists have established that the human brain communicates directly with the immune system, sending commands that control the body’s inflammatory response to infection and autoimmune diseases. The mechanisim of this communication is through the body's 10th cranial nerve, the vagus nerve. The vagus nerve is really a bundle of nerves that originates at the top of the spinal cord and enervates everything from the neck down to the colon. The fibers of the vagus nerve are parasympathetic (meaning they communicate the body's 'rest and digest' commands, as opposed to 'fight or flight' messages). The vagus nerve stimulates muscles in the vocal chamber, affects heart rate, gland function, digestion, and has even been linked to receptors for oxytocin- the feel good hormone/neurotransmitter of parenthood, hugs and bonding.



Anyhoo, most any yoga routine will stimulate the vagus nerve, and one very stimulating aspect of yoga is the Ujjayi breathing. If you just do a slow breathing rate (2 to 4 breaths per minute), you will turn on the vagus. However, creating airwave resistance (as in ujjayi) enhances the the vagus nerve input to the brain.

While I can't connect the dots for you from vagus stimulus to improved immune function, and not getting sick for three years, the vagus has been the focus of intense scientific study for a number of years. Treatments targeting vagus stimulation have already been approved by the USFDA for depression and epilepsy. When functioning properly, doctors say it is an essential element in bolstering the body's natural ability to fight against stress, inflammation and toxins that can trigger illness. "Without doubt, nourishing the brain and Vagus Nerve holds the key to many aspects of maintaining good health," commented Dr. Paul Yanick, author of "Quantum Medicine: A Guide to the New Medicine of the 21st Century."

So get out there and put on some stretchy pants and stimulate that vagus! It might keep you from getting sick!