ACSM Recommends Tai Chi in their 2011 Guidance for Prescribing Exercise
The American College of Sports Medicine, in their 2011 Position Stand, Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory, Musculoskeletal, and Neuromotor Fitness in Apparently Healthy Adults:
Guidance for Prescribing Exercise, recommends people perform 20-30 minutes of neuromotor (functional fitness) training 2 – 3 times a week.
ACSM states that tai chi is the most widely studied functional fitness program and that it has been shown to be effective in improving balance, agility, motor control, proprioception, and quality of life.
Although limited by the number of tai chi studies on younger populations, evidence suggests that exercises, such as tai chi, which involve balance and agility, may reduce anterior cruciate ligament (ACL) injuries and reduce recurrent ankle injuries in men and women athletes. Tai chi really does have something to offer just about anyone.
The position statement also states that a program of regular exercise that includes cardiorespiratory, resistance, flexibility, and neuromotor exercise training beyond activities of daily living to improve and maintain physical fitness and health is essential for most adults.
Multifaceted physical activities such as tai chi involves varying combinations of neuromotor exercise, resistance exercise, and flexibility exercise. Neuromotor exercise training is beneficial as part of a comprehensive exercise program for older persons, especially to improve balance, agility, muscle strength, and reduce the risk of falls.
Here is a link to a summary: http://www.greatist.com/fitness/new-acsm-exercise-guidelines/.
Here is a link where you can read or download the entire 2011 ACSM Position Statement: http://journals.lww.com/acsm-msse/Fulltext/2011/07000/Quantity_and_Quality_of_Exercise_for_Developing.26.aspx.