Objective: The cardiovascular control center restricts maximum blood flow due to the limited capacity of the heart to increase cardiac output (CO). This is achieved by vasoconstriction mediated by sympathetic nerves. Sympathetic nerve activity (SNA) is increased by central command, baro- and exercise pressor reflexes (EPR). Against the background of high SNA, local functional sympatholysis governs the redistribution of the available CO to tissues with highest metabolite concentrations. Activation of SNA and local sympatholysis act together in a complex integrative fashion, which is difficult to grasp for many students. Therefore, an experiment was designed sufficient to demonstrate these regulatory principles, but simple enough to be conducted during basic physiology lab courses. Methods: Perfusion of both forearms was measured simultaneously on medical students with strain-gauge venous occlusion plethysmography at rest and after combined hand-grip (right arm only) and leg exercise (bicycle ergometer). Blood pressure and pulse frequency (HF) were determined at rest and after exercise. Peripheral perfusion resistance of forearms were calculated according to Poiseuille's law from mean arterial pressure (MAP) and blood flow. Results: An increase of MAP and HF indicated sympathetic activation. Blood flow increased while resistance decreased in the exercising arm. In the resting forearm blood flow was unchanged but resistance significantly increased. These effects were highly reproducible. Conclusions: The following concepts of regulation in circulation and perfusion are apparent: 1) functional hyperemia with increased blood flow and reduced resistance in working muscle, 2) activation of the sympathetic nervous system, probably by EPR activation and central command, 3) local functional sympatholysis leading to raised resistance with reduced blood flow in resting muscle and 4) the existence of myogenic vasoconstriction activated by increased blood pressure.