Racial and gender effects on the relaxation response: implications for the development of hypertension.

This study was designed to explore the effect of race and gender on the forehead muscle tension and finger temperature response to biofeedback-assisted relaxation training in individuals with normal blood pressure. Forty-five subjects-18 Black and 27 White, 25 males and 20 females-participated in eight sessions of autogenic relaxation training and thermal biofeedback. Multivariate analysis of variance of the variables measured at baseline (systolic BP diastolic BP sodium excretion, anxiety) was significant for gender Univariate analysis showed males different from females in DBP Na(+) excretion, and trait anxiety. Pretest values of muscle tension were similar by gender, but pretest temperatures were lower in males than females. Repeated measures ANOVA for muscle tension showed a significant effect of period. For temperature a significant effect of period, gender and gender x period was observed. Males increased temperature more than females. There was no effect of history of hypertension on the relaxation response. Multiple regression performed on change in muscle tension and change in temperature showed that pretest muscle tension predicted change in muscle tension. Four variables contributed to the variance in change in temperature: pretest temperature, sodium excretion, and state and trait anxiety.