• Change in tidal volume and minute ventilation during guided breathing
• change in breathing frequency, tidal volume, and minute ventilation during overnight sleep at home after 28 days of guided breathing

• Changes in blood pressure, end tidal CO2 and heart rate variability [ Time Frame: during guided breathing and 28 days later ] [ Designated as safety issue: No ]
• Changes in 24 hour blood pressure and urinary marinobufagenin excretion [ Time Frame: after 28 days of guided breathing ] [ Designated as safety issue: No ]

• Changes in blood pressure, end tidal CO2 and heart rate variability during guided breathing
• changes in above measures, 24 hour blood pressure, and urinary marinobufagenin excretion after 28 days of guided breathing

The purpose of this study is to investigate the nature of the physiological reasons for the decreases in resting blood pressure that can result from systematic practice of computer-guided breathing exercises or meditative relaxation.

In this randomized clinical trial, persons with moderately elevated blood pressure will be trained in either computer-guided breathing exercises or meditative relaxation. The computer-guided breathing exercise involves listening to tones of ascending and descending pitch to which breathing is entrained to low frequencies over a 15 minute interval. The meditative relaxation involves passive attention to natural breathing for the same duration. Participants will perform these breathing exercises daily at home for four weeks. Before and after the intervention, respiratory, cardiovascular, and urinary endogenous digitalis-like factors will be systematically recorded to determine the extent to which chronic neuroendocrine changes underlie the reductions in blood pressure.

• Behavioral: Guided Breathing
• Device: Resperate

• Meles E, Giannattasio C, Failla M, Gentile G, Capra A, Mancia G. Nonpharmacologic treatment of hypertension by respiratory exercise in the home setting. Am J Hypertens. 2004 Apr;17(4):370-4.
• Elliot WJ, Izzo JL Jr, White WB, Rosing DR, Snyder CS, Alter A, Gavish B, Black HR. Graded blood pressure reduction in hypertensive outpatients associated with use of a device to assist with slow breathing. J Clin Hypertens (Greenwich). 2004 Oct;6(10):553-9; quiz 560-1.
• Grossman E, Grossman A, Schein MH, Zimlichman R, Gavish B. Breathing-control lowers blood pressure. J Hum Hypertens. 2001 Apr;15(4):263-9.

Inclusion Criteria:

• Over 21 years
• Systolic blood pressure 130-160 or diastolic blood pressure 85-100

Exclusion Criteria:

• More than one antihypertensive medication
• Beta blockers, angiotensin converting enzyme inhibitors or angiotensin receptor blockers
• History of coronary artery disease, heart failure, stroke, angina or coronary revascularization
• Kidney disease, defined as plasma creatinine > 1.5mg/dL
• Diabetes, defined by insulin or oral hypoglycemic medication or blood sugar > 126mg/dL
• Pulmonary disease, defined as chronic obstructive pulmonary disease, bronchitis, asthma, or use of inhaler
• Upper respiratory infection during past 30 days
• Medication that affects central nervous system function
• Steroid use
• Current pregnancy or lactation within past six months
• Current birth control medication or hormone replacement therapy
• Condition that in the judgment of the Principal Investigator is incompatible with the research study