This is the randomized trial to explore the effect of behavioral modification program (Tai Chi vs. self management) on adults with metabolic syndrome. The outcome variables include health behavior, metabolic syndrome indicators, quality of life.

1. venue: the individuals with diagnosis of metabolic syndrome are recruiting from university hospital outpatient clinic or primary clinic.
2. inclusion criteria: diagnosed of metabolic syndrome, agree to participate either programs, no history of participating regular exercise program past 6 months.
3. intervention: The behavioral modification program consisting of Tai Chi exercise (twice a week for 12 weeks) and self-management program (6 sessions every two weeks) is provided to the participants who randomly assigned to either group. Short form Yang style Tai Chi (16 movements) were led by trained Tai Chi practitioners, and self-management program were provided by nurse educators.

Inclusion Criteria:

• diagnosis of metabolic syndrome
• adults who agree to participate either behavioral modification programs for 12 weeks
• be able to understand the questionnaire and follow the exercise or education program

Exclusion Criteria:

• who attend regular exercise program past 6 months

blood sample will be analyzed by the lab technician without identity of the group assignment. self-reported questionnaire is also used