Mean BP changes for progressive muscle relaxation, simple
biofeedback, relaxation-assisted biofeedback, and stress management training ranged on
systolic BP from −2.3 mm Hg to +4.3 mm Hg, and on diastolic BP from −2.0 mm Hg to +2.4
mm Hg. These results were not statistically significant. Studies on the Transcendental
Meditation program formed the largest category, with six clinical trials and 449 research
subjects. The mean BP reductions across these trials were −5.0 mm Hg systolic and −2.8 mm
Hg diastolic and were statistically significant (P = 0.0002 and P = 0.02).