Effects of HG on standing in a representative subject. MAP, HR, CO, TPR from subject undergoing the orthostatic stress of standing (left). MAP, HR, CO, TPR from same subject undergoing orthostatic stress of standing after initiating the 80% maximum HG maneuver (right). MAP increases from baseline with handgrip and the decrease in MAP is somewhat reduced. Changes in CO, HR and TPR are blunted during stand + HG compared with stand alone.