A method of treating sepsis and septic shock is using a passive simulated exercise device is disclosed. The exercise device functions to increase pulsatile shear stress (friction) to the vascular endothelium. Increased shear stress stimulates release of beneficial mediators from the endothelium into the circulation that promote integrity of the endothelial barrier as well as to prevent its disruption by suppressing inflammation and oxidative stress. The latter is the basis for the deleterious effects of sepsis and septic shock. Failure to control integrity of the endothelial barrier promotes excessive leakage of fluid and proteins from the vasculature into surrounding interstitial fluid that can rapidly escalate into major morbidity, shock and death.