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If you look for me on an average weekday night, say around 8:30pm, you will likely find me swathed in spandex, drenched in sweat, and working my tail off in a hot, humid, and dimly lit room full of other sweaty and scantily clad people. The music is pounding, but not as loud as my heart is in my ears. I’m dizzy and exhausted—more likely that not, I’m experiencing discomfort, if not outright pain. When I tell people that I’m addicted to this experience, their eyes widen in wonderment as they question my mental stability: “I don’t understand why anyone would want to do that!”
Then again, this is almost always what I hear from people who haven’t really tried it.
Yoga practice has spent the last quarter century going from a yuppie health fad to an expected piece of advice from nearly any physician. Most of the advice boils down to the fact that improving your strength and flexibility through regular practice of yoga postures (“asanas”) is excellent for your physical and mental well-being. In my three years as a bumbling new yogi, this turned out to be true; I often joke that yoga membership is worth the pretty penny because it serves as my gym, my therapist, and my chiropractor all rolled into one.
“Well,” you say, “couldn’t it simply be regular exercise in general?" To which I would reply, “Absolutely! Regular exercise of any kind is a major life bonus.” However, recent research into clinical applications and the neurobiology of different types of exercise seems to demonstrate that yoga has a competitive advantage over other types of aerobic activity, especially for emotional stability and well-being.
If someone were to give a short explanation of what a yoga practice consists of, it is maybe intuitively obvious why it might combat depressive symptoms and promote mood stability; although a yoga series can seem like just a lot of boring stretching when you are beginning, students who persevere for a week or two will realize that the real point is to gain mindful control over your body and emotions. It encourages you to work with yourself patiently, swallow your pride, do the best you can at that moment without overextending. Myself, I have learned to realize that breath and focus can save me from the most stressful of physical postures. (Did I mention you also lose weight and feel awesome? You lose weight and feel awesome!) I often hear instructors say that learning to control emotions that boil over in frustration and discomfort through physically demanding postures in the classroom is an excellent way to train your emotions for real life stress and hardship.
And you know what? Research so far says that somehow, it does exactly that. Yoga, when compared to other forms of relatively low impact physical activity (such as walking) appears to reduce anxiety and assuage the symptoms of depression. In one study, there was no significant difference in outcomes between treating stress and anxiety with yoga versus cognitive behavioral therapy.
So in short, we seem to know that this is happening, but how? Our understanding of the chemical effects of exercise on mood remains vastly limited—it was only in the last few years that scientists discovered that the so-called “runner’s high” may have nothing to do with endorphins, and is more likely thanks to endogenous cannabinoids (yep, that’s right, the body’s very own homemade marijuana)! However, recent research on the neurochemistry of yoga provides some clues about how yoga might exert anxiolytic effects: two fascinating randomized controlled Magnetic Resonance Spectroscopy studies by Streeter and colleagues demonstrate that regular practice of gentle yoga, but not walking, releases a chemical called GABA in the thalamus.1,2 GABA is sort of the “grand inhibitor” in the brain, and plays a central role in suppressing neural activity3. Classical anti-anxiety medications, such as benzodiazepines, work by encouraging the release of GABA in the central nervous system. GABA was shown to be significantly higher in the brains of those subjects who had been doing yoga. The study also compared GABA levels directly before an after an hour of yoga, and showed a 27% increase! GABA is what alcohol mimics, by temporarily binding to the same chemical receptors; you can thank GABA receptor binding for those feelings of relaxation and decreased anxiety that come with enjoying an adult beverage. Streeter et al’s findings suggest that somehow, the meditative stretching and breathing that yoga involves is signaling the brain to release calming chemicals, which play out their mood effects in the hours following a session of yoga. Though research remains very preliminary regarding the specifics of such a mechanism, we do know that the connections in the brain use chemical signals to actually change their strength and configuration. It may be that the GABA released over a period of regular yoga practice can help boost baseline levels of this calming chemical, helping the brain rewire itself to have a calmer, less anxious response in the face of everyday stressors.
So if you’re like me, finishing a long day of work and school, asking yourself, “hmm… beer or yoga?”, remember that the calm you get from beer goes away, but the calm you get from yoga might stay.e
Edit: After hearing a couple of reactions, I just wanted to say that I'm not encouraging anybody to adopt yoga and forego all other types of treatment for anxiety and/or depression! For the time being, I think it is best considered a complementary technique. Also, there's no real reason to think that it's ONLY yoga that creates a GABA-ergic response--similar techniques that combine exercise and mindful control of the body/mind, such as Tai Chi (or even Crossfit, as suggested by a friend of mine), could certainly create a similar biological response!
1. Streeter CC, Jensen JE, Perlmutter RM, et al. Yoga Asana sessions increase brain GABA levels: a pilot study. J Altern Complement Med. 2007;13:419-426.
2. Streeter CC, Whitfield TH, Owen L, et al. Effects of yoga versus walking on
mood, anxiety, and brain GABA levels: a randomized controlled MRS study. J
Altern Complement Med 2010;16:1145–52
3. Gray, J. A., & McNaughton, N. (2000). The neuropsychology of anxiety: An enquiry into the functions of the septo-hippocampal system (2nd ed.). New York: Oxford University Press.
4. Granath J, Ingvarsson S, von Thiele U, Lundberg U. Stress management: a randomized study of cognitive behavioural therapy and yoga. Cogn Behav Ther. 2006;35:3-10.
