Tai chi chuan exercise decreases A1C levels along with increase of regulatory T-cells and decrease of cytotoxic T-cell population in type 2 diabetic patients.

T ype 2 diabetes is a metabolic syndrome associated with chronic inflammat ion (1–3) . Al though exercise training has been proven beneficial in treatment of type 2 diabetes (4,5), this preventive and therapeutic modality remains underused (5). Recently, evidence (6) indicates that physical inactivity can increase proinflammatory burden independently of obesity, and exercise may induce anti-inflammatory mediators (7). Strenuous exercise has been shown to augment proinflammatory reaction (8,9) and compromise adaptive immunity with a higher risk of upper respiratory tract infections (9,10). Moreover, strenuous exercise might also potentiate hypoglycemia in elderly diabetic patients (11). In contrast, certain studies show that moderate exercise enhances T-cell function (12) and decreases respiratory infections (13), which suggests that the volume of exercise is a critical element of inducing a positive or negative immune response in diabetic patients. Tai Chi Chuan (TCC) exercise, a traditional Chinese martial art that is classified as a moderate exercise because it does not demand 55% of maximal oxygen intake (14), can benefit balance and cardiovascular and respiratory function (14–16). We have previously shown (17) that a regular TCC exercise for 12 weeks significantly enhances functional mobility and regulatory T-cell function of normal adult volunteers; however, we could not assess the effect of TCC exercise on glycemic improvement. In this study, we recruited type 2 diabetic patients to participate in the TCC program to investigate the effect of TCC exercise on the metabolism of blood glucose and lymphocyte subpopulations.