Tai chi is often described as "meditation in motion," but it might well be called "medication in motion." There is growing evidence that this mind-body practice, which originated in China as a martial art, has value in treating or preventing many health problems. And you can get started even if you aren't in top shape or the best of health.

In this low-impact, slow-motion exercise, you go without pausing through a series of motions named for animal actions - for example, "white crane spreads its wings" - or martial arts moves, such as "box both ears." As you move, you breathe deeply and naturally, focusing your attention - as in some kinds of meditation - on your bodily sensations.

Tai chi differs from other types of exercise in several respects. The movements are usually circular and never forced, the muscles are relaxed rather than tensed, the joints are not fully extended or bent, and connective tissues are not stretched. Tai chi can be easily adapted for anyone, from the most fit to people confined to wheelchairs or recovering from surgery.

A growing body of carefully conducted research is building a compelling case for tai chi as an adjunct to standard medical treatment for the prevention and rehabilitation of many conditions commonly associated with age. An adjunct therapy is one that's used together with primary medical treatments, either to address a disease itself or its primary symptoms, or, more generally, to improve a patient's functioning and quality of life.

Tai chi in motion

A tai chi class might include these parts.

Warm-up. Easy motions, such as shoulder circles, turning the head from side to side, or rocking back and forth, help you to loosen your muscles and joints and focus on your breath and body.

Instruction and practice of tai chi forms. Short forms - forms are sets of movements - may include a dozen or fewer movements; long forms may include hundreds. Different styles require smaller or larger movements. A short form with smaller, slower movements is usually recommended at the beginning, especially if you're older or not in good condition.

Qigong (or chi kung). Translated as "breath work" or "energy work," this consists of a few minutes of gentle breathing sometimes combined with movement. The idea is to help relax the mind and mobilize the body's energy. Qigong may be practiced standing, sitting, or lying down.

Getting started

The benefits of tai chi are generally greatest if you begin before you develop a chronic illness or functional limitations. Tai chi is very safe, and no fancy equipment is needed, so it's easy to get started. Here's some advice for doing so.

Don't be intimidated by the language. Names like Yang, Wu, and Cheng are given to various branches of tai chi, in honor of people who devised the sets of movements called forms. Certain programs emphasize the martial arts aspect of tai chi rather than its potential for healing and stress reduction. In some forms, you learn long sequences of movements, while others involve shorter series and focus more on breathing and meditation. The name is less important than finding an approach that matches your interests and needs.

Check with your doctor. If you have a limiting musculoskeletal problem or medical condition - or if you take medications that can make you dizzy or lightheaded - check with your medical care team before starting tai chi. Given its excellent safety record, chances are that you'll be encouraged to try it.

Consider observing and taking a class. Taking a class may be the best way to learn tai chi. Seeing a teacher in action, getting feedback, and experiencing the camaraderie of a group are all pluses. Most teachers will let you observe the class first to see if you feel comfortable with the approach and atmosphere. Instruction can be individualized. Ask about classes at your local Y, senior center, or community education center.

If you'd rather learn at home, you can buy or rent videos or stream classes geared to your interests and fitness needs (see "Selected resources"). Although there are some excellent tai chi books, it can be difficult to appreciate the flow of movements from still photos or illustrations.

Talk to the instructor. There's no standard training or licensing for tai chi instructors, so you'll need to rely on recommendations from friends or clinicians and, of course, your own judgment. Look for an experienced teacher who will accommodate individual health concerns or levels of coordination and fitness.

Dress comfortably. Choose loose-fitting clothes that don't restrict your range of motion. You can practice barefoot or in lightweight, comfortable, and flexible shoes. Tai chi shoes are available, but ones you find in your closet will probably work fine. You'll need shoes that won't slip and can provide enough support to help you balance but have soles thin enough to allow you to feel the ground. Running shoes, designed to propel you forward, are usually unsuitable.

Gauge your progress. Most beginning programs and tai chi interventions tested in medical research last at least 12 weeks, with instruction once or twice a week and practice at home. By the end of that time, you should know whether you enjoy tai chi, and you may already notice positive physical and psychological changes.

No pain, big gains

Although tai chi is slow and gentle and doesn't leave you breathless, it addresses the key components of fitness - muscle strength, flexibility, balance, and, to a lesser degree, aerobic conditioning. Here are some research-backed benefits of tai chi.

Muscle strength. Tai chi can improve both lower-body strength and upper-body strength. When practiced regularly, tai chi can be comparable to resistance training and brisk walking.

Although you aren't working with weights or resistance bands, the unsupported arm exercise involved in tai chi strengthens your upper body. Tai chi strengthens both the lower and upper extremities and the core muscles of the back and abdomen.

Flexibility. Tai chi can boost upper- and lower-body flexibility as well as strength.

Balance. Tai chi improves balance and, according to some studies, reduces falls. Proprioception - the ability to sense the position of one's body in space - declines with age. Tai chi helps train this sense, which is a function of sensory neurons in the inner ear and stretch receptors in the muscles and ligaments. Tai chi also improves muscle strength and flexibility, which makes it easier to recover from a stumble. Fear of falling can make you more likely to fall; some studies have found that tai chi training helps reduce that fear.

Aerobic conditioning. Depending on the speed and size of the movements, tai chi can provide some aerobic benefits. If your clinician advises a more intense cardio workout with a higher heart rate than tai chi can offer, you may need something more aerobic as well.