Local and systemic vascular hemodynamic response to passive static stretching in young healthy humans

The aim of the present study was to determine the acute effects of passive static stretching (PSS) on femoral blood flow (FBF) in a stretched and non-stretched limb. Our hypothesis was that PSS would increase FBF in the stretched limb mainly through local vasodilator mechanisms. PSS effects may be expected also in the non-stretched limb possibly through an imbalance between the systemic hemodynamic control and the local vasodilator response. To this purpose, eight young healthy individuals (age: 22\ub13 yrs) underwent PSS (5 cycles of 45 s stretch/15 s rest) of the knee extensors of the dominant limb. Femoral artery blood velocity and diameter were taken from both limbs by ultrasound. FBF was then calculated. PSS increased FBF by 3c78% in the stretched limb (from 495\ub1110 to 882\ub1121 ml/min; P<0.05). FBF returned to baseline within the end of the 45 s stretch. Conversely, FBF decreased transitory by 3c71% (from 334\ub1155 to 138\ub117 ml/min; P