Racial differences in the relaxation response of hypertensives.

Racial differences in the relaxation response of hypertensives maintained on diuretic were investigated by comparing blood pressure, muscle tension, and hand temperature changes occurring with biofeedback assisted relaxation. Resting blood pressures were not different in blacks compared with whites. Both black and white subjects decreased diastolic blood pressure significantly from baseline values, but only whites significantly decreased systolic blood pressure. Though both blacks and whites significantly decreased forehead muscle tension, black subjects showed no changes in finger temperature while whites increased temperature significantly. The lack of change in finger temperature in blacks may be a reflection of the increased peripheral resistance previously associated with the greater incidence of hypertension in the American black population.