This research is being performed by Frank Dinenno, Ph.D. of the Health and Exercise Science Department, and also by Dennis Larson, M.D. and Gary Luckasen, M.D., of the Heart Center of the Rockies. Trained graduate students, undergraduate students, research assistants, or research associates are assisting with the research. These studies are paid for by the National Institute on Aging, a part of the US Government. This project has approval from the CSU Institutional Review Board under the study title: Regional Blood Flow Control and Vascular Function: Effects of Aging and Regular Physical Activity.