Other common name(s): hatha yoga
Scientific/medical name(s): none
Yoga is a form of nonaerobic exercise that involves a program of precise posture, breathing exercises, and meditation. In ancient Sanskrit, the word yoga means “union.”
Yoga can be a useful method to help relieve some symptoms of chronic diseases such as cancer, arthritis, and heart disease and can lead to increased relaxation and physical fitness. Available scientific evidence does not support yoga as an effective treatment for cancer or any other disease; however, it may enhance quality of life. Some cancer treatment centers even offer yoga in addition to standard medical treatment.
How is it promoted for use?
Yoga is promoted as a system of personal development. It is a way of life that combines ethical standards, dietary guidelines, physical movements, and meditation to create a union of mind, body, and spirit. Yoga is said to cultivate prana, which means vital energy or life force and is similar to qi (or chi) in traditional Chinese medicine. People who practice yoga claim it leads to a state of physical health, relaxation, happiness, peace, and tranquility. There is some evidence that shows that yoga can lower stress, increase strength, and provide a good form of exercise.
Supporters also claim yoga can help eliminate insomnia, increase stamina, and help with smoking cessation. They further claim that the mastery of yoga can give people supernormal mental and physical powers. Yogis, who are masters and teachers of yoga, claim they can obtain heightened senses, overcome hunger and thirst, and develop almost total control over physical processes such as heart rate and breathing.
What does it involve?
There are more than a hundred different types of yoga practiced in the United States today. Most of them are based on hatha yoga, which uses movement, breathing exercises, and meditation to achieve a connection between mind, body, and spirit.
The goal of yoga is perfect concentration to attain Samadhi -- pure awareness without mental distractions. Hatha yoga uses forbearance, breath control, withdrawal of senses, attention, concentration, and meditation to attain Samadhi. The 3 most commonly used aspects of yoga today include the postures of hatha yoga (called asanas), the breathing techniques of pranayama, and meditation.
Practitioners say yoga should be done either at the beginning or the end of the day. A typical session can last between 20 minutes and an hour. A yoga session starts with the person sitting in an upright position and performing gentle movements, all of which are done very slowly, while taking slow, deep breaths from the abdomen. A session may also include guided relaxation, meditation, and sometimes visualization. It often ends with the chanting of a meaningful word or phrase, called a mantra, to achieve a deeper state of relaxation. Yoga requires several sessions a week in order for a person to become proficient. Yoga can be practiced at home without a teacher or in group classes. Many books and videos on yoga are also available.
What is the history behind it?
First practiced in India more than 5,000 years ago, yoga is one of the oldest mind-body health systems in existence. In the United States, yoga was first practiced by the Concord transcendentalists in the 1840s, but it did not become well known until the 1880s when the English translation of Yoga Sutras was published. This ancient book gave a detailed description of yoga techniques and the quest for Samadhi, which is central to yoga beliefs.
Four traditional yoga paths are meditative (Raja Yoga), service (Karma Yoga), wisdom (Jnana Yoga), and devotional (Bhakti Yoga). Hatha Yoga is based on a part of Raja Yoga, and is the best known form of yoga. In the United States, it is what most people mean when they refer to yoga.
Today, some health plans offer members access to yoga instructors as a form of exercise and relaxation. Health clubs, community centers, adult education centers, and individual teachers offer classes in many subtypes of Hatha Yoga, including ananda, ashtanga, bikram, integral, Iyengar, kripalu, and kundalini.
What is the evidence?
Research has shown that yoga can be used to control physical functions such as blood pressure, heart rate, breathing, metabolism, body temperature, brain waves, and skin resistance. This can result in improved physical fitness, lower levels of stress, and increased feelings of relaxation and well-being.
According to a report to the National Institutes of Health, there is also some evidence to suggest yoga may be helpful when used with conventional medical treatment to help relieve some of the symptoms linked to cancer, asthma, diabetes, drug addiction, high blood pressure, heart disease, and migraine headaches. Other studies have shown limited benefit. Yoga may also help to reduce cholesterol levels when used with diet and exercise. Randomized clinical trials have shown that yoga can help relieve the pain of arthritis and may also help anxiety, stress, and depression.
One small clinical trial showed that people with lymphoma reported fewer sleep disturbances, fell asleep more quickly, and slept longer after a seven-week yoga program, compared to patients who did not participate in yoga. However, the patients showed no improvement in depression or fatigue. More well-designed research studies are needed to confirm all of these findings. Recent studies of cancer survivors, especially women who have had breast cancer, suggest yoga may help improve several aspects of quality of life.
Are there any possible problems or complications?
People with cancer and chronic conditions such as arthritis and heart disease should talk to their doctor before starting any type of therapy that involves movement of joints and muscles. Some yoga postures are hard to achieve, and damage can occur from overstretching joints and ligaments. There have been rare reports of damaged nerves or discs in the spine. Rarely, eye damage can occur due to increased pressure in the eyes when doing headstands. This can also worsen glaucoma in some people. Blood vessels can sometimes become blocked due to yoga postures, damaging the brain or other parts of the body.
Pregnant women may want to avoid postures that cause pressure on the uterus, such as body twists. People who are sick, dehydrated, or pregnant may be harmed by bikram yoga, which is a vigorous workout practiced in a very warm, humid room (usually between 95° and 105° F).
Relying on this type of treatment alone and avoiding or delaying conventional medical care for cancer may have serious health consequences.
More information from your American Cancer Society
The following information on complementary and alternative therapies may also be helpful to you. These materials may be found on our Web site (www.cancer.org) or ordered from our toll-free number (1-800-ACS-2345).
The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management
About yoga. Asheville Yoga Center Web site. Accessed at http://www.youryoga.com/ayc/~info.html on May 23, 2008.
Bower JE, Woolery A, Sternlieb B, Garet D. Yoga for cancer patients and survivors. Cancer Control. 2005;12:165-171.
Cohen L, Warneke C, Fouladi RT, Rodriguez MA, Chaoul-Reich A. Psychological adjustment and sleep quality in a randomized trial of the effects of a Tibetan yoga intervention in patients with lymphoma. Cancer. 2004;100:2253-2260.
Ernst E, ed. The Desktop Guide to Complementary and Alternative Medicine: An Evidence-Based Approach. New York: Mosby; 2001.
Garfinkel MS, Schumacher HR Jr, Husain A, Levy M, Reshetar RA. Evaluation of a yoga based regimen for treatment of osteoarthritis of the hands. J Rheumatol. 1994;21:2341-2343.
Garfinkel MS, Singhal A, Katz WA, Allan DA, Reshetar R, Schumacher HR Jr. Yoga-based intervention for carpal tunnel syndrome: a randomized trial. JAMA. 1998;280:1601-1603.
McDonald A, Burjan E, Martin S. Yoga for patients and carers in a palliative day care setting. Int J Palliat Nurs. 2006;12:519-523.
Moadel AB, Shah C, Wylie-Rosett J, et al. Randomized controlled trial of yoga among a multiethnic sample of breast cancer patients: effects on quality of life. J Clin Oncol. 2007;25:4387-4395.
National Institutes of Health. Alternative Medicine: Expanding Medical Horizons: A Report to the National Institutes of Health on Alternative Medical Systems and Practices in the United States. Washington, DC: US Government Printing Office; 1994. NIH publication 94-066.
Taylor E. Yoga and meditation. Altern Ther Health Med.1995;1:77-78.
The tree of classical yoga/Hinduism. Classical Yoga Hindu Academy Web site. Accessed at http://www.classicalyoga.org/following_were_article_published.htm on May 23, 2008.
Yoga. Aetna InteliHealth Web site. Accessed at http://www.intelihealth.com/IH/ihtIH?d=dmtContent&c=358876 on May 23, 2008.
Note: This information may not cover all possible claims, uses, actions, precautions, side effects or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for consultation with your doctor, who is familiar with your medical situation.
Last Revised: 11/01/2008