Yoga in Altering Mechanistic Outcomes in Hypertension

The proposed study will assess the effects of yoga postures and slow, deep breathing in altering oxidative stress, vascular function, and blood pressure.

The purpose of this study is to determine the mechanism by which yoga lowers blood pressure in hypertensive adults. Free radicals and enzyme activity will be analyzed from isolated immune cells and blood pressure and vascular health will be assessed at baseline and at weeks 4, 8, and 12 during the interventions or control conditions. Sedentary adults (ages 40-60 years) with elevated blood pressure or stage I hypertension will be recruited and randomized to 12 weeks of yoga, slow, deep breathing, or waitlist control conditions. Yoga classes will be completed 3 times weekly at Texas State University and slow, deep breathing interventions will be completed at home 5 times weekly. Participants assigned to the waitlist/sham control group will also complete 5- 20-minute breathing exercises per week at home before being re-randomization at week 12. Three testing sessions will be completed at the beginning of the study: 1) familiarization and screening for elevated blood pressure or hypertension and other exclusion criteria; 2) confirmation of elevated blood pressure or hypertension via addition seated blood pressure measurements and 24-hour ambulatory blood pressure and 3-day physical activity monitoring; and 3) blood marker assessment and endothelial function measurements. All outcomes will be measured at baseline and at 4-week intervals throughout the 12-week data collection period in all 3 groups. At each follow up visit after randomization, testing will be completed over the course of 2 sessions: 1) ambulatory blood pressure monitor and physical activity monitoring and 2) blood marker and endothelial function measurements. At the end of the waitlist sham/control period, waitlisted participants will be rerandomized to yoga or slow, deep breathing interventions. Once re-randomized, participants in each group will complete follow up testing 4,8, and 12 weeks into their respective interventions.

12-week yoga intervention in which 60-minute classes are completed at Texas State University 3 times per week

Blood draws will be performed at baseline and at weeks 4, 8, and 12 during the study after randomization and analyzed for free radicals after white blood cells are separated from whole blood.

A portion of the white blood cells isolated from a whole blood sample will be frozen and later analyzed for enzyme activity. This will be completed for blood samples obtained at baseline and weeks 4, 8, and 12.

An automated cuff will be worn for 24 hours while the devices takes automatic measurements every 30 minutes.

A cuff will placed around the forearm while an ultrasound probe is held on the upper arm to obtain a brachial artery image. The forearm cuff will be inflated for 5 minutes, then ultrasound images of the upper arm will be obtained for 3 minutes after cuff deflation.

Exclusion Criteria: pregnancy (tests will be administered to all premenopausal females at initial screening and follow up visits); having taken blood pressure or statin medications within the past 3 months (statins have been demonstrated to reduce oxidative stress); infection (viral or other) within the past 4 weeks; having adrenal or endocrine tumors (these could impact blood pressure); renal disease defined as an estimate glomerular filtration rate (eGFR) of less than 60 (creatinine will be tested at initial screening and eGFR will be calculated); hyperaldosteronism; prior myocardial infarction; known coronary heart disease; personal history of stroke; heart failure; cardiac arrhythmias; chronic obstructive pulmonary disease, asthma, or other airflow obstructions; recent chest pain or dyspnea; orthopedic limitations that preclude the execution of yoga postures; current insulin dependence; xvi) chronic inflammatory conditions (e.g., rheumatoid arthritis, lupus, HIV/AIDS, ulcerative colitis, or Crohn's disease); currently taking steroid or other anti-inflammatory medication; currently undergoing chemotherapy or radiation; having practiced yoga or slow, deep breathing at least once weekly within the past 6 months; or currently smoking or having quit within the last 6 months.