The Valsalva maneuver Dr. Ramo described would increase total peripheral resistance from hand grasping and contracting gluts. A pure Valsalva maneuver is exhaling against a closed glottis. If this is done by itself, there is a complex response of heart rate, first falling, then rising. This is shown below for a 10 second Valsalva. The initial rise in aortic pressure and reflex bradycardia is due to compression of thoracic arteries and increased flow from compressed lungs to left atrium. This is followed by a drop and mean pressure due to reduced venous return to heart and reflex tachycardia. http://www.cvphysiology.com/Hemodynamics/H014.htm
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