What are the benefits of yoga for overall wellness?

Of the eight “limbs” of classical yoga, formulated over 2,000 years ago, only one relates to physical fitness as we now think of it. The others include
ethical principles, the flow of vital energy, and meditation as paths toward self-knowledge and enlightenment. These days, many people have a
more casual attitude to yoga. But even if you just drop in to an occasional class, you’ll spend time on breathing and concentration exercises that you
wouldn’t encounter in a typical gym routine—part of the discipline’s continuing commitment to a state of wellness defined much more broadly than
the usual fitness markers.


Science, needless to say, seeks to classify and measure these benefits. One theory is that yoga helps to control the “fight-or-flight” response
that physical, mental, or emotional stress triggers in your body. The stress hormone cortisol, for instance, triggers a cascade of physiologic,
behavioral, and psychological effects through the endocrine system; similarly, your nervous system responds to stress by sending signals to elevate
heart rate, blood viscosity, and blood pressure. If these responses are triggered too often, your body gets run down and susceptible to illness.
Several studies have found that yoga programs can lower levels of cortisol throughout the day
compared yoga with “supportive therapy” in a group of 88 breast cancer patients. (In contrast, yoga failed to change cortisol levels in another 2009
study of women with rheumatoid arthritis.) Various other studies have seen positive effects from yoga on outcomes like perceived stress, mood,
and sleep patterns.


Of course, researchers have observed many of the same benefits from non-yogic exercise. A Rutgers University study in 2008 pitted hatha
yoga against strength training in a head-to-head comparison, putting subjects through 50-minute sessions and then measuring the effects on
anxiety, tension, calmness, and other mental health variables at 15-minute intervals afterwards. Both yoga and strength training had positive effects
—yoga improved scores on anxiety and calmness, while resistance training improved all variables. Interestingly, yoga’s impact was most
pronounced immediately afterwards, then began to fade within an hour. Strength training, in contrast, produced effects that intensified as recovery
progressed, suggesting a longer-lasting result.
It’s important to note that the weights session was perceived by participants to be “moderate exercise,” while the yoga session was “light
exercise”—a difference that could explain why weights had a bigger effect. But, lead author Joseph Pellegrino explains, the details of the sessions
were carefully chosen to mimic how people really do weights and yoga, in order to do a real-world comparison.

Other studies have found, in general, more similarities than differences between yoga and other forms of exercise. A review of 81 studies by
University of Maryland researchers in 2010 concluded that “yoga may be as effective as or better than exercise” for a variety of health-related
outcomes but acknowledged a lack of rigorous studies. For now, researchers haven’t been able to isolate and identify any secret ingredients that
yoga offers and other forms of exercise don’t. But it’s clear that, whether you choose a yoga class or a relaxing bike ride along a waterfront path,
you’ll be getting benefits for both body and mind.