Yoga is an ancient Indian system of health practices that includes gentle stretching exercises, physical postures, breathing exercises, and meditation.
Yoga is one of the original Vedic sciences that were codified more than 5,000 years ago in the sacred Hindu philosophical and spiritual texts called the Vedas. "Yoga" is a broad term with several meanings. One is "right path," encompassing all aspects of living healthfully and harmoniously in the world. Another, derived from the Sanskrit, is "union" – the integration of body, mind and spirit.
The three main practices of yoga include gentle stretching exercises and postures (asanas), breathing exercises (pranayama), and meditation. Together they comprise an elaborate system originally intended to bring the practitioner closer to God. The physical aspects of the practices were designed to calm the mind and prepare both mind and body for meditation, the final step toward heightened spiritual awareness. In fact, the ultimate goal of yoga is spiritual fulfillment and tranquility, not physical health as such.
In Indian tradition, a "yogi" is a person who has devoted his or her life to the mastery of the path of yoga in all its facets. The wandering saddhus, or holy men, of India are often depicted as quiet and peaceful, even while holding a seemingly difficult yoga posture or position.
In modern times, yogis have contributed a great deal to our understanding of mind/body integration. In the 1960s and 1970s, several yoga masters participated in experiments at the Menninger Foundation in Topeka, Kansas, and in India, to explore their ability to control bodily functions such as heart rate, blood pressure, and body temperature. These experiments demonstrated previously unrecognized human capabilities, and inspired the development of biofeedback and other forms of mind/body medicine in the West.
Yoga has become a popular health practice in the West primarily for its affects on flexibility and relaxation. There are many varieties, but the most common and most basic form is hatha yoga, "the yoga of vitality" (ha means sun, tha means moon).
At the heart of yogic theory are its concepts of prana and our energy system. Prana is roughly equivalent to Qi (pronounced "chee") in Traditional Chinese Medicine, and vital force or life force in Western terms. Prana enters the body through each breath, and circulates through a vast network of energy pathways called nadis. The nadi system is believed to parallel the nervous system, and, thus, each breath brings vital energy to every cell. There are three major nadis moving up through the center of the body; these are called the ida, pingala, and shushumna. The three intersect at the chakras, which are seven energy centers forming a line from the pelvis to the crown of the head. A detailed understanding of the nadis is the basis of the yogic breathing practice of pranayama, which is described in "What to Expect in a Yoga Program," below.
In modern terms, yoga asanas (postures and stretches) would be considered a means of integrating the nerves and the muscles. In yogic terms they are thought to stimulate the flow of prana, or life force, through our entire energetic anatomy. This can have great importance in healing since specific illnesses are believed to be associated with energy blockages in specific chakras. For example, difficulties in the uterus or prostate, which are centered deeply in the region of the second chakra, are helped by yoga postures that stimulate the flow through that area.
The yogic perspective also views the joints of the body as minor chakras. By making our joints more flexible, we are opening them and allowing greater flow of the life force throughout the body. Furthermore, as our muscles, ligaments, and other soft tissue become more flexible, they, too, are more able to conduct a balanced and harmonious flow of vital energy through our bodies.
There is not a strong history of research in yoga, but in recent years it has increasingly been examined as a way to complement conventional medicine. For example, a controlled study of 20 migraine sufferers found that after four months of yoga therapy, there was a significant reduction in the number of headaches, the severity of the headaches, and in the level of stress experienced by the study participants. In addition, there was less use of medication to control or manage the headaches(1). A study of 60 adults with chronic neck or shoulder pain found that a program of yoga-like stretching exercises was more effective than training in progressive muscle relaxation for reducing tension and pain levels(2).
In a controlled study of 42 adults with carpal tunnel syndrome, those receiving yoga training twice a week for 8 weeks had significant improvements in grip strength and reductions in pain(3). There is also evidence that yoga may help with asthma: in a controlled study of 17 adults with asthma, those who took three sessions of yoga per week for 16 weeks had better relaxation, improved attitude, a higher tolerance for exercise, and made less use of inhalers(4). Another study found evidence that yoga may help reduce the need for medication in patients with obsessive compulsive disorder(5).
At the University of Massachusetts Medical School, researchers have pioneered a mindfulness-based stress reduction program that includes meditation and yoga for people with chronic pain. Impressive research findings from this program have been instrumental in introducing yoga as part of an effective pain control approach in hospitals and clinics across the United States(6).
What Are the Potential Uses of Yoga?
Because of its generalized benefits, many health conditions may benefit from the practice of yoga. Conditions for which yoga is commonly used include:
migraine and tension headaches
Who Teaches Yoga and What is Their Training?
Yoga teachers come from all walks of life, including both lay people and licensed health care providers. Some teach from a particular spiritual orientation, while others focus on yoga purely as a health practice.
There is no licensing or regulation for the teaching of yoga. Typically, teachers have been practicing yoga themselves for many years under the guidance or training of someone more experienced. Teacher training courses of varying lengths are offered in many holistic health centers across the country, and around the world. The Center for Mindfulness in Medicine, Health Care, and Society, at the University of Massachusetts Medical School, trains health care providers in how to integrate yoga and meditation into comprehensive treatment for people with serious illness or chronic pain.
In considering a teacher, always inquire about their training and experience. Sit in on a class. Ask your primary physician for a referral, or seek recommendations from acquaintances. Make an informed decision before committing to a teacher or program.
Is Yoga Safe?
There should be no adverse effects from yoga if done properly. Although there may be some initial stiffness, this should pass as the body adapts to the positions. However, over-stretching can result in discomfort. Stretching should be gentle and within comfortable limits, particularly in areas of the body that have been previously injured or are unconditioned.
There are no contraindications for yoga per se. People with hemophilia or who are otherwise vulnerable to injury should practice only under close supervision. People with high blood pressure should avoid inverted postures such as head and shoulder stands. It should be noted that people who have recently had a back injury or surgery should obtain the advice of their primary physician before beginning a yoga program. Some postures are not recommended during pregnancy. Always advise your yoga instructor of any illness or injury.
What to Expect in a Yoga Program
Yoga can be taught through private lessons, but in most cases it is taught in a group class format. Typically a class meets once or more per week, and each session follows a regime of gentle stretching and breathing exercises, ending with a meditation.
One popular asana, known as the Sun Salute, combines stretching and balance with mild aerobic exercise. Depending on one’s symptoms or medical condition, specific asanas may be used to stimulate certain organs, or to improve the circulation of blood and energy through a particular organ or system in the body.
Pranayama involves a set of breathing exercises that have the effects of soothing the nervous system, inducing relaxation, regulating the breathing process, and balancing the hemispheres of the brain. The primary technique is alternate-nostril breathing, in which you close off one nostril by pressing a finger against it, while exhaling and inhaling through the other. Then you switch sides, and repeat the process through the other nostril. This alternating process is continued for five minutes or so.
The benefits of yoga become may become apparent soon after beginning to practice. You may feel the impact on your energy and flexibility with the first session, even if you’ve never done yoga before. The body has a great potential for "plasticity," and any attention you give to even slightly increasing your current level of flexibility will be accompanied by a tangible sense of greater energy flowing through your body.
William Collinge, Ph.D., M.P.H.
1. Latha D; Kaliappan KV. Efficacy of yoga therapy in the management of headaches. Journal of Indian Psychology. 1992 Jan-Jul; Vol 10(1-2): 41-47
2. Kay JA; Carlson CR. The role of stretch-based relaxation in the treatment of chronic neck tension. Behavior Therapy. 1992 Sum; Vol 23(3): 423-431
3. Garfinkel MS; Singhal A; Katz WA et al. Yoga-based intervention for carpal tunnel syndrome: a randomized trial. JAMA, 280(18):1601-3 1998 Nov 11
4. Vedanthan PK; Kesavalu LN; Murthy KC et al. Clinical study of yoga techniques in university students with asthma: a controlled study. Allergy Asthma Proc, 19(1):3-9 1998 Jan-Feb
5. Shannahoff-Khalsa DS; Beckett LR. Clinical case report: efficacy of yogic techniques in the treatment of obsessive compulsive disorders. Int J Neurosci, 85(1-2):1-17 1996 Mar
6. Kabat-Zinn J; Lipworth L; Burney RJ. The clinical use of mindfulness meditation for the self-regulation of chronic pain. Behav Med, 8(2):163-90 1985 Jun