There are five major styles, which differ in intensity and emphasis.
Yang style is the most popular style and is characterized by a basic choreographed form of from 24 to over 220 movements done slowly and smoothly.
Yang style forms are similar in terms of how hard the exerciser is working.
Typically, to the outside observer, it appears not much exercise is being done.
But the exerciser had a different experience.
A question often comes up, "Is tai chi an aerobic exercise?" To answer this question I directly measured several tai chi chuan students and instructors using state of the art medical devices that measured the amount of oxygen they used while doing the Yang Style form.
All fell within the range of walking between 2.
5 and 3.
5 miles per hour in terms of energy expenditure.
I will focus on the two Certified tai chi teachers who were tested.
I looked at the oxygen consumption of two Yang style t'ai-chi ch'uan instructors to determine their energy expenditure.
Oxygen consumption is the most fundamental way to measure energy expenditure.
From this number the calories (Kcal) used per minute can be determined.
I measured the oxygen consumption of two expert Yang stylists to determine energy expenditure.
Subject I (S-I) performed a 20 minute form and ranged from VE of 10.
8 L/m to 18.
5 L/m; VO2 of 549 to 795 ml/m; VO2 of 7.
4 to 12.
4 ml/kg/m; RER from 0.
72 to 0.
Mean values for S-I was VE 13.
8 L/m; VO2 669 ml/m; VO2 10.
4 ml/kg/m; RER 0.
Subject II (S-II) did an 8 min form with VE from 15.
3 to 20.
3 L/m; VO2 from 750 to 828 ml/m; VO2 from 9.
3 to 11.
1 ml/kg/m; RER from 0.
70 to 0.
Mean values for S-II were VE 17.
3 L/m; VO2 777 ml/m; VO2 10.
4 ml/kg/m; RER 0.
Both subjects had similar numbers and averaged VO2 of 10.
4 ml/kg/min and RER of 0.
This data suggests that t'ai-chi ch'uan form studied is a suitable aerobic exercise for those people with low maximal capacities, such as in the 6 MET range and can be substituted for walking programs (3 mph pace).
This is similar to results found by other researchers.
Those students with medical issues should be evaluated by their physicians as to the benefits of the art.
Those students with high blood pressure should be monitored to assure you that the movements do not cause any untoward raising of blood pressure.
Conclusion: The Yang style slow forms studied are examples of low intensity aerobic exercise.
Reference: Kurland, H.
, SPORTS MEDICINE, TRAINING AND REHABILITATION, 1992, Vol.
# 3, p 228.