How Yoga Works

The Vedas and the Bhagavad Gita praised yoga as an important spiritual element, but the Yoga Sutras of Patanjali, written sometime in the second century B.C., provided the first real how-to text. The scholar Patanjali wrote that there are eight limbs, or steps, of yoga:

Modern-day yogis may recognize asana and pranayama among those limbs, as they're the ones that form the basis of a typical yoga class. But Patanjali's text doesn't include much information on the asanas that we practice today; the only posture he wrote about was a seated meditation pose. Though he wrote that physical exercise would help students prepare their bodies for concentration and meditation, he didn't provide much information about how to perform those exercises. That information seems to have been handed down orally from teacher to student in India, and if it was in writing, those texts have been lost.

So how did yoga become about handstands and lotus pose? The history of hatha yoga, or yoga that emphasizes physical exercise, jumps to the 1800s and the Mysore Palace. Mysore is considered one of the birthplaces of modern yoga due to the royal family's enthusiasm for ancient Indian arts. In the early 1800s, a Mysore prince wrote the Sritattvanidhi, one of the first yoga manuals to include physical postures that has been located.

A century later, the Maharaja of Mysore installed a yoga school in the palace and invited T. Krishnamacharya to teach there. Krishnamacharya had traveled India, studying with many master yogis, and was renowned for his mastery of asanas. When he started studying at Mysore in 1931, he began developing and teaching ashtanga yoga, an athletic form of yoga that involves linking many postures rhythmically. At Mysore, Krishnamacharya taught K. Pattabhi Jois and B.K.S. Iyengar; Jois would continue studying ashtanga and popularize it around the world, while Iyengar developed the form of yoga that emphasizes precision and alignment and bears his name. These types of yoga are among the most popular in the U.S., and on the next page, we'll examine how they arrived from Mysore.

Current yogis owe a debt of gratitude to the Maharaja at Mysore for yoga's popularity around the world. Not only did the Maharaja fund the school at which Krishnamacharya taught his students, who would go on to be influential in their own right, he also paid for these talented yogis to travel around India demonstrating yoga. People from the West began traveling to Mysore to study with these masters, and the gurus began going west themselves, starting in the late 1890s.

Pierre Bernard and Indra Devi are two people who worked hard to entrench yoga in the U.S. Bernard was a showman who relied on some of the more mystical aspects of yoga to draw a crowd; he would claim to feel no pain as doctors stuck needles in his body, thanks to yogic training. He traveled the world giving speeches on yoga's benefits, and then he set up a yoga retreat center on the Hudson River that taught the celebrities of the early 1900s.

Devi rejected that yogic mysticism and put the influence solely on the physical benefits of yoga when she opened her studio in Hollywood in 1947. Devi, who had studied with Krishnamacharya at Mysore, realized that movie stars would be effective prosthelytizers for yoga, and she recruited Greta Garbo, Gloria Swanson and Marilyn Monroe to come to her classes. After working with Devi, Monroe gave credit to yoga for her great legs [source: Mishra].

In the 1950s, Richard Hittleman continued what Devi had begun: repackaging yoga as a physical exercise regimen while minimizing the spiritual, meditative parts. Hittleman taught yoga on television and sold many exercise books with his methods. During the 1960s and '70s, when hippies reigned, there was a brief resurgence of interest in the more spiritual aspects of yoga, but those quickly dropped away in the early 1990s, when yoga became a workout for mainstream America. Since then, we think of yoga as "hatha yoga," all exercise with a modicum of spirituality.

Some yoga purists and Hindu groups are angry that yoga in the U.S. has lost that spiritual element; they point out that these exercises were only done to prepare the body for the kind of concentration and meditation that would be necessary to understand the divine. Others might point out that Americans approach yoga as physical exercise but soon discover the mental and emotional benefits that these traditional yogis associate with the practice. It seems that the battle over what yoga means, and what it should mean, will continue in the U.S. While some yogis bemoan the rise of the $100 pair of yoga pants and the competitions that seem to go against all the self-acceptance and mental clarity that true yoga stands for, other yogis claim that yoga's evolution in America is nothing new, that yoga has always been more about change and adaptation than unyielding tradition.

One thing is for sure -- yoga isn't going away anytime soon. But not all yoga is the same -- on the next page, we'll consider what types of yoga are commonly practiced.

As we mentioned, hatha yoga, or yoga based on physical postures, is the most common type of yoga in the United States. But many types of yoga fall under the hatha yoga banner, so it's important to investigate what type of class you might be getting at a studio or gym.

People who want an aerobic-type workout tend to be drawn to ashtanga and power yoga. With these styles of yoga, you flow quickly from one pose to the next. You'll probably work up a sweat with ashtanga or power yoga, but if you'll definitely perspire if you choose to practice Bikram yoga or hot yoga. In a Bikram class, you'll perform 26 postures twice in a room that's upwards of 100 degrees Fahrenheit (37.7 degrees Celsius). The high temperatures are supposed to make your body more flexible and speed the removal of toxins from the body.

There are plenty of yoga options if you'd like to take things a little easier, though. One popular style is Iyengar yoga, which uses many of the same postures as ashtanga yoga. However, the positions are held for a longer period of time, and there's a greater emphasis on alignment. You might use props like blocks, belts, chairs and blankets to go deeper into the pose.

Jivamukti yoga delves deeper into some of the spiritual elements of yoga. While a typical class will include ashtanga-style poses, it will also include meditation, chanting and spiritual readings. You can also expect to chant and meditate on mantras if you explore Kundalini yoga, which is aimed at waking up a coil of energy at the base of the spine. Ananda yoga involves performing poses while meditating on a specific affirmation for each one.

One particularly gentle style of yoga is viniyoga. A viniyoga class will move slowly through the poses, and instructors will tailor the practice to a student's individual needs and abilities. Integrative yoga therapy is also specialized; this type of yoga was designed for patients with conditions like depression, AIDS and heart disease and focuses on the mind's role in healing the body.

Integrative yoga therapy provides an example of how yoga can help someone who is sick, but plenty of yoga practitioners go to class for the health benefits they receive even when they're well. On the next page, we'll explore how yoga purports to protect the mind and the body.

Yoga gets credit for a variety of health benefits, like improving flexibility, posture and endurance. These factors, in combination with stronger muscles, may help to prevent falls in the elderly. Yoga is thought to drain the lymph nodes of toxins and lower levels of stress hormones in the body, which can relaxes the mind and help the immune system remain strong enough to fight off infection.

Yoga lowers blood pressure and and eases constipation. It may also reduce hormones that cause depression while releasing the neurochemicals that prevent it. And yoga can relieve chronic pain conditions such as fibromyalgia, back pain and arthritis. Some people who practice yoga claim it helps them work and sleep better, while plenty of people believe that yoga keeps them sane in the midst of this crazy world.

There are some studies that back up these health claims, but research into yoga's health benefits has been somewhat slow. In the United States, pharmaceutical companies fund many of the clinical research trials, and since the essence of yoga can't be condensed down to a pill, there's not much of an incentive to test it. Some of the studies that have been done only evaluate yoga as an adjunct to other treatment regimens, so it's impossible to tell the exact impact that yoga can have.

Many people say that we'll never be able to completely prove the health benefits of yoga, as the ways in which the mind and the body work together are too mysterious to unpack. But while yoga seems to cure a whole variety of ills, it can cause problems for students who push themselves too far. In 2006, approximately 4,500 people went to the emergency room after practicing yoga, with ailments ranging from strained muscles to back and neck injuries [source: Perrine]. That's why it's important to know what kind of yoga class you're getting yourself into, learn the proper alignment of each pose and listen to your body's limits during your practice.

If you'd like to learn more about yoga, there are plenty of links on the next page to check out.