The purpose of this experimental study was to examine blood pressure changes
of healthy subjects in response to position changes (from supine to level and
head-down side lying) and percussion. Twenty male and 20 female volunteers
with a mean age of 25.9 years were divided randomly into four groups so that
each group consisted of 5 men and 5 women. After resting supine for 20
minutes, subjects assumed a level or a head-down side-lying position (-10°) for
6 minutes. During this 6 minutes, percussion was applied to two of the four
groups. Systolic and diastolic blood pressures significantly decreased when
subjects turned from a supine to a level or a head-down side-lying position. The
decreases lasted the length of time the side-lying position was maintained. The
blood pressure responses to head-down side lying did not significantly differ
from the responses to level side lying. The blood pressure responses to the level
and the head-down side-lying positions with percuss