Ischemia reperfusion injury (IRI) leads to a temporary decrease in macrovascular function, but whether IRI causes microvascular dysfunction is not known. Resistance exercise involves muscular contractions that can make downstream tissues ischemic and may ischemic preconditioning the vasculature against endothelial IRI. We tested the hypothesis that an acute resistance exercise prior to IRI would prevent or attenuate IRI induced macro- and microvascular dysfunction in healthy young adults. Nineteen healthy young subjects (age 22±2 years) were randomly assigned to either a resistance exercise group (n=10) as a model to produce ischemic preconditioning or a control group (n=9). The resistance exercise was performed eight types of systemic resistance exercise. Ischemia was induced by inflating a cuff placed around the upper arm to 200 mm Hg for 20 minutes. carotid-femoral pulse wave velocity (cfPWV) as index of macrovascular function and reactive hyperemia index (RHI) using by fingertip arterial tonometry as index of microvascular function were measured at baselines and 15 and 30 minutes after ischemia reperfusion injury. cfPWV was increased in control group but decreased in resistance exercise group following IRI. There was a significant interaction effect between resistance exercise group and control group for cfPWV (p=0.022). The RHI was unaffected following IRI and also unchanged by a resistance exercise. These findings show that ischemia reperfusion caused macrovascular dysfunction but not microvascular dysfunction. However, this macrovascular dysfunction following IRI was not shown in the resistance exercise group. Thus, an acute bout of resistance exercise prior to ischemia may prevent against ischemia reperfusion injury induced macrovascular dysfunction.