Effects of Tai Chi on glucose homeostasis and insulin sensitivity in older adults with type 2 diabetes: a randomised double-blind sham-exercise-controlled trial.
BACKGROUND
a large proportion of adults with type 2 diabetes remain sedentary despite evidence of benefits from exercise for type 2 diabetes. Simplified Yang Tai Chi has been shown in one study to have no effect on insulin sensitivity in older adults. However, a modified Tai Chi form, Tai Chi for Diabetes (TCD) has recently been composed, claiming to improve diabetes control.


METHODS
subjects were randomised to Tai Chi or sham exercise, twice a week for 16 weeks. Primary outcomes were insulin resistance 72 h post-exercise (HOMA2-IR), and long-term glucose control (HbA(1c)).


RESULTS
thirty-eight subjects (65 +/- 7.8 years, 79% women) were enrolled. Baseline BMI was 32.2 +/- 6.3 kg/m(2), 84% had osteoarthritis, 76% hypertension, and 34% cardiac disease. There was one dropout, no adverse events, and median compliance was 100 (0-100)%. There were no effects of time or group assignment on insulin resistance or HbA(1c) ( -0.07 +/- 0.4% Tai Chi versus 0.12 +/- 0.3% Sham; P = 0.13) at 16 weeks. Improvement in HbA(1c) was related to decreased body fat (r = 0.484, P = 0.004) and improvement in insulin resistance was related to decreased body fat (r = 0.37, P = 0.03) and central adiposity (r = 0.38, P = 0.02), as well as increased fat-free mass (r = -0.46, P = 0.005).


CONCLUSIONS
TCD did not improve glucose homeostasis or insulin sensitivity measured 72 h after the last bout of exercise. More intense forms of Tai Chi may be required to produce the body composition changes associated with metabolic benefits in type 2 diabetes.
Tsang
Tracey
T
School of Exercise and Sport Science, Faculty of Health Sciences, University of Sydney, Australia. ttsa6920@mail.usyd.edu.au
Orr
Rhonda
R
Lam
Paul
P
Comino
Elizabeth
E
Singh
Maria Fiatarone
MF
D000058:Accidental Falls; D000203:Activities of Daily Living / Q000523:psychology; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D010349:Patient Compliance / Q000523:psychology; D011788:Quality of Life / Q000523:psychology; D026302:Tai Ji / Q000523:psychology
D001786:Blood Glucose