Changes in brachial and femoral artery vascular conductance in non-exercising limbs during handgrip exercise

The purpose of this study was to determine the difference in vascular conductance changes in brachial and femoral artery (BVC, FVC) of non-exercising limbs during handgrip exercise at different intensities. Six subjects performed rhythmic handgrip exercise, which consisted of 2-second contraction and 2-second relaxation at the intensities of 15%, 30%, and 45% of maximal voluntary contraction (MVC). Brachial and femoral artery blood flow (Doppler ultrasound method) of non-exercising limbs, blood pressure, and heart rate were measured. The BVC during exercise at lower intensities (15% and 30%MVC) and FVC during exercise at any of three intensities did not change significantly. However, BVC significantly decreased at 45%MVC when the exercise was continued to longer than 60% of maximal endurance time (P<0.05). These results suggest that FVC of the non-exercising limb dose not change during handgrip exercise at the intensity lower than 45%MVC, but BVC of the non-exercising limb change during handgrip exercise depending on the exercise intensity and duration.