Definition

Yoga is a mind-body therapy that connects the body, breath, and mind to energize and balance the whole person. It uses physical postures, breathing exercises, and meditation to improve overall well-being.

Descriptions of yoga, the word means "union" in Sanskrit, appear more than 2,000 years ago, and yoga was practiced thousands of years before that. Today, millions of Americans of all ages and fitness levels practice yoga regularly. Although yoga is a spiritual practice for many, most Westerners do yoga for exercise or to reduce stress.

In its traditional form, yoga is considered a complete lifestyle that provides a path to spiritual enlightenment.

The dimensions of yoga are sometimes depicted as a tree with eight limbs:

• Pranayama (breathing)
• Asana (postures)
• Yama (restraint)
• Niyama (healthy observances)
• Pratyahara (sensory withdrawal)
• Dharana (concentration)
• Dhyana (meditation)
• Samadhi (higher consciousness)

The practice of yoga came to the United States in the 1890s with the teachings of a guru named Swami Vivekananda. Yoga became popular in the 1960s because of growing interest in mind-body therapies. Today, yoga is often done as exercise, separated from its traditional spiritual roots. In this form, yoga is taught at local YMCAs, health clubs, and yoga centers. It is often suggested by doctors to reduce stress in people with high blood pressure and heart disease, and to improve flexibility in people with arthritis.

Different branches or paths of yoga have developed, including:

• Bhakti yoga. This form of yoga aims to take all of the love in one's heart and direct it toward the divine. By seeing God in all of creation, the person has respect for all life and is encouraged to treat others generously.
• Hatha yoga. This is the most common form of yoga in the United States. It emphasizes physical postures or exercises, known as asanas, with the goal of balancing the opposites in one's life. During the exercises, flexing is followed by extension, a rounded back is followed by an arched back, and physical exercises are followed by meditations.
• Jnana yoga. This form of yoga emphasizes deep contemplation. Practitioners seek Jnana, or "wisdom," through meditation. The goal is to be one with God.
• Karma yoga. This form of yoga is based on the philosophy that "yesterday's actions determine today's circumstances." Practitioners of Karma yoga make a conscious decision to perform selfless acts of kindness. By making today's actions positive, they hope to improve tomorrow's circumstances for both themselves and others.
• Raja yoga. Known in India as "the royal (raj) road to reintegration," Raja yoga blends the four layers of self: the body, the individual consciousness, the individual subconsciousness, and the universal and infinite consciousness. Raja yoga is most concerned with the mind and spirit and emphasizes meditation.
• Tantra yoga. Like Hatha yoga, practitioners of Tantra yoga seek to balance the opposites in their lives. They also try to break free of the "six enemies", which are physical longing, anger, greed, vanity, obsession, and jealousy; and the "eight fetters", which are hatred, apprehension, fear, shyness, hypocrisy, pride of ancestry, vanity of culture, and egotism, by using discipline, training, and rituals.

Hatha yoga is often a general term that is used for many different types or styles of yoga. If a class is called "Hatha yoga," it includes both breathing and physical exercises or postures. Other styles of yoga can be more intense. Among the more popular styles of yoga are:

• Ashtanga or Power yoga, a more demanding workout where you constantly move from one posture to another ("flow").
• Bikram or Hot yoga, a series of 26 asanas (postures) done in a room that is 95 to 100 degrees. The goal is to warm and stretch the muscles, ligaments, and tendons, and to purify the body through sweat.
• Integral, a gentle type of yoga that may include breathing exercises, chanting, and meditation.
• Iyengar, emphasizes great attention to detail and precise alignment of the body, and holding poses for long periods of time.
• Kundalini, emphasizes the effects of breath on the postures, in order to free energy in the lower body to move upwards.
• Viniyoga, adapts postures to each person's needs and abilities, and synchronizes breath and postures. Breath leads the body into each posture.

Scientists do not know exactly how yoga works for good health. Some say it reduces stress like other mind-body therapies, and others believe that yoga causes the release of endorphins, natural painkillers and "feel good" chemicals in the brain. Studies show yoga can lower heart rate and blood pressure, increase muscle relaxation, and increase breathing capacity.

All branches of yoga mentioned above use three major techniques: breathing, exercise (asana or postures), and meditation. These three techniques improve health in many ways:

• Breathing. In yoga, breathwork is known as pranayama. Pranayama increases blood flow and reduces oxygen consumption. That brings more oxygen to your brain, and improves the way your body uses oxygen. Breathing exercises can also increase how much air you draw into your lungs. Getting lots of air into your lungs helps you feel alert and focused.
• Asanas (postures). Provide a gentle-to-intense workout that boosts strength, flexibility, and balance.
• Meditation. Quiets the mind and causes both physical and emotional relaxation, which helps reduce blood pressure, chronic pain, anxiety, and cholesterol levels.

A typical yoga session

Most people learn yoga by taking a group class with an experienced instructor, but one-on-one sessions are also available. These private or semi-private sessions cost more. Classes usually last from 45 to 90 minutes and start with warm-up exercises, move to a guided series of yoga postures designed to stretch and tone all areas of the body, and end with deep relaxation or meditation. Throughout the class, the teacher helps you with breath control and proper body alignment.

Your instructor will encourage you to practice at home to get the most from yoga.

Yoga improves fitness, lowers blood pressure, promotes relaxation and self confidence, and reduces stress and anxiety. People who practice yoga tend to have good coordination, posture, flexibility, range of motion, concentration, sleep habits, and digestion. Yoga is a complementary therapy that has been used with conventional medicine to help treat a wide range of health problems, but it does not cure any disease.

Studies show that yoga may help the following conditions:

• Anxiety and stress
• Arthritis, both osteoarthritis and rheumatoid arthritis
• Asthma
• Cancer, as an additional therapy to reduce stress and strengthen the immune system. One study of 68 people with breast cancer found that those who practiced yoga had less anxiety and depression compared to those who did not. Even the DNA damage from radiotherapy was slightly less in the yoga group compared to the control group.
• Long-lasting back pain
• Depression
• Diabetes
• Addiction
• Parkinson disease
• Epilepsy
• Heart disease, by lowering cholesterol levels, lowering blood pressure, lessening stress, and reducing how often people had chest pain and how severe it was (when combined with a healthy diet)
• High blood pressure
• Hormonal problems
• Irritable bowel syndrome
• Lung diseases
• Pregnancy
• Migraine headaches
• Sleep problems among the elderly

In addition, yoga postures that stretch and strengthen joints in the upper body may improve grip strength and reduce pain in people with carpal tunnel syndrome.

Some people may feel stiff as their bodies get used to different postures. As with any physical activity, yoga can cause injury if not done correctly. It is important to practice yoga with a trained teacher.

Be sure to check with your doctor before trying yoga if you have high blood pressure, heart disease, arthritis, or a recent back injury, as you would with any exercise program. Choose one of the gentler forms of yoga.

Pregnant women may need to avoid some postures. Special classes are available for expecting mothers. Be sure to call your doctor if any exercises cause headaches, muscle cramps, dizziness, or severe pain in your back, legs, or joints.

Remember that yoga instructors are not doctors. Only you and your doctor can decide if a certain yoga posture is too hard or might injure you depending on your condition. If you feel like a posture might cause injury, DO NOT do it or ask your instructor to modify it for you.

International Association of Yoga Therapists (IAYT) -- www.iayt.org

Yoga Alliance -- www.yogaalliance.org

Yoga Journal -- www.yogajournal.com

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