Tai Chi, Physiologic Complexity, and Healthy Aging

Study Overview
=================
Brief Summary
-----------------
To evaluate the effects of Tai Chi-a mind-body exercise--on age-related loss of physiological complexity (using fractal and entropy based measures), and to understand the relationship between complexity, function and adaptability, we will conduct a two-arm prospective randomized clinical trial. Our overarching goal is to evaluate if six months of Tai Chi training, compared to a waitlist control receiving standard medical care, can enhance physiological complexity and adaptability in older Tai Chi-naïve adults. Secondary goals of the study are to characterize the relationship between complexity biomarkers, measures of function, and resilience. This pilot study will inform a future more definitive trial by providing information on recruitment and retention, compliance, dose-dependent effects, preliminary estimates of effect size, and the optimal biomarkers of complexity, function, and adaptive capacity.

Detailed Description
-----------------
Specific Aim #1: To determine if 6 months of Tai Chi training can increase complexity, function, and adaptive capacity of multiple physiological systems in older healthy adults. Specific Aim #2: To determine the relationships between biomarkers of physiological complexity, conventional measures of function and adaptive capacity. Statistical regression models will be used to determine relationships, both at baseline and overtime, between a) complexity biomarkers and measures of physical and cognitive function, and b) complexity biomarkers and adaptive capacity. Elucidating these relationships will further inform the interpretation of complexity biomarkers and provide insights into underlying component mechanisms contributing to complex physiological dynamics.

Official Title
-----------------
Tai Chi, Physiologic Complexity, and Healthy Aging

Conditions
-----------------
Healthy Aging

Intervention / Treatment
-----------------
* Behavioral: Tai Chi Exercise
* Behavioral: Tai Chi


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Ages 50-79 Living within the Greater Boston area Willing to adhere to 6 month Tai Chi training protocol Exclusion Criteria: Chronic medical conditions, including: cardiovascular disease (myocardial infarction, angina, atrial fibrillation, or presence of a pacemaker), stroke, respiratory disease requiring daily use of an inhaler, diabetes mellitus, malignancies, neurological conditions (e.g., seizure disorder, Parkinson's, peripheral neuropathy), or other neuromuscular or musculoskeletal (requiring chronic use of pain medication) disease Acute medical condition requiring hospitalization within the past 6 months Self-reported (current) smoking or alcohol/drug abuse Uncontrolled Hypertension (resting SBP > 160 or DBP > 100mm Hg) Abnormal heart rate (resting HR > 100 bpm; <50bpm) Abnormal ECG (supraventricular tachyarrhythmia, atrial fibrillation, significant ST wave abnormality, 2nd and 3rd degree heart block) Pregnancy Current use of prescription medications including cardio- or vaso-active drugs and medications that can affect autonomic function including Beta agonists and antagonists, drugs with anticholinergic properties (e.g. tricyclic antidepressants or anti psychotics), and cholinesterase inhibitor Self-reported inability to walk continuously for 15 minutes unassisted Regular Tai Chi practice within past 5 years Regular participation in physical exercise on average 4 or more times per week

Ages Eligible for Study
-----------------
Minimum Age: 50 Years
Maximum Age: 79 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Usual Care<br> | Behavioral: Tai Chi<br>* Usual care, individuals attend testing sessions for 6 months with testing at times 0, 3, and 6 months. Individuals in Usual Care receive 3 months of Tai Chi at the study end.<br>|
| Experimental: Tai Chi<br>Individuals will take part in community-based Tai Chi classes twice a week for 6 months as well as practice Tai Chi outside of class twice a week for the same 6 month period. | Behavioral: Tai Chi Exercise<br>* Practicing Tai Chi exercise 4 times a week for 6 months - twice in a classroom and twice independently<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Heart rate complexity | Beat-to-beat variation measured using ECG for a 30 minute during seated quiet resting | 0, 3, and 6 months | 
| Change in Center of Pressure complexity | Center of pressure (COP) dynamics during quiet standing with eyes open | 0, 3 and 6 months |