The endocannabinoid system (ECS) is widely found in central and peripheral systems, and the immune system. Moderate-intensity aerobic exercise has shown to increase circulatory endocannabinoids. In this study, we will study Tai Chi, a mind-body moderate-intensity exercise, intervention for its effects on ECS in women. A pre-post design trial will be conducted on 18 qualified subjects. We will measure plasma eCB levels at baseline, before and after 4th session of Tai Chi. All data will be analyzed statistically at p<0.05.

The endocannabinoid system (ECS) is widely found in central and peripheral systems, and the immune system. Emerging studies have shown endocannabinoid plays a role in appetite, pain sensation, control of chronic pain, macronutrient metabolism, mood/mood disorder, and regulation of immune cell functions. Moderate-intensity aerobic exercise has shown to increase circulatory endocannabinoids. Moderate-intensity exercise improves cognition, memory, and wellbeing in adults. Exercisers experience decreased tension, depression, and anger. Therefore, these findings in humans suggest a likely relationship for exercise effecting well-being via ECS. In this study, we will study Tai Chi, a mind-body moderate-intensity exercise, intervention for its effects on ECS in women. A pre-post design trial will be conducted on 15 qualified subjects. All subjects will be assigned to Tai Chi group for one week including 3 sessions, 60 minutes per session, on 3 non-consecutive days. We will measure plasma eCB levels at baseline, before and after 4th session of Tai Chi. All data will be analyzed statistically at p<0.05.

Inclusion Criteria:

1. Postmenopausal women (menopause is defined as the absence of menstrual period for 12 months, not related to pregnancy/lactation, hormonal contraception). Age 40-70 years old with BMI between 25-35 kg/m2.
2. English literacy.

Exclusion Criteria:

1. prior experience with mind-body practice (e.g., TC, Qi Gong, yoga, meditation).
2. Severe medical limitations (i.e., dementia, symptomatic heart or vascular disease, or recent stroke) precluding full participation.
3. Medical/neurologic or other systemic diseases affecting the musculoskeletal systems (i.e. polio/Parkinson's/ multiple sclerosis, etc. in addition to cerebral vascular accident or stroke) and diabetes with peripheral neuropathy affecting their sensory/balance.
4. taking pain/anti-inflammatory and sleep medications within the 3 months before study starts.
5. taking hormone-replacement therapy within the 3 months before study starts.