Tai Chi, which means supreme ultimate, is a traditional Chinese martial art (Koh, 1981) and a mind-body exercise. It involves a series of fluid, continuous, graceful, dancelike postures, and the performance of movements known as forms (Yang, 2010). The graceful body movements engage continuous body and trunk rotation, flexion/extension of the hips and knees, postural alignment, and the coordination of the arms—integrated by
mental concentration, the balanced shifting of body weight, muscle relaxation, and breath control. Movements are performed in a slow, rhythmic, and well-controlled manner (Clark, 2011).

There are several styles of Tai Chi that are currently practiced: Chen (quick and slow large movements), Yang (slow large movements), Wu (midpaced, compact movements), and Sun (quick, compact movements) (Jou, 1983). Each style has a characteristic protocol that differs from the other styles in the postures or forms included, the order in which they appear, the pace at which movements are executed, and the level of difficulty; however, the basic principles are the same (Yang, 1991). For example, one significant difference between the Chen and Yang styles is that Yang movements are relaxed, evenly paced, and graceful. Yang is the most popular Tai Chi practiced by older adults (Jou, 1983). In comparison, the Chen style is characterized by alternating slow, gentle movements with quick and vigorous ones, and restrained and controlled actions, which reflect a more martial origin (Yang, 1991). Most Tai Chi movements were named after animals, such as “white crane spreads its wings” and “grasp the bird’s tail” (Koh, 1981).

There are a few simplified forms of the ancient Tai Chi. For example, the Simplified Tai-Chi Exercise Program (STEP), developed by Chen, Chen, and Huang (2006), encompasses three phases: warm-up, Tai Chi exercises, and cool-down. In the warm-up phase, nine exercises are designed to loosen the body from head to toe; the second phase includes 12 easy-tolearn and easy-to-perform Tai Chi movements; three activities during the cool-down phase help the body to return to a preintervention state of rest. STEP differs from traditional Tai Chi styles in that it incorporates fewer leg movements, fewer knee bends, and less-complicated hand gestures. It was specifically designed for older adults suffering from chronic illness (Chen et al., 2006).