Upper-respiratory viral infection in humans is mediated by a number of factors. Anti-viral proteins, changes in gene expression, and the release of specific signaling molecules are all elements of a healthy immune response to a potential pathogen. These complex immune processes and components have not yet been well characterized. In this project, we specifically explored the nature of non-cellular constituents that help fight viral infection. Nasal lavage—a technique in which saline solution is used to rinse the nasal cavity, allowing for the collection and solvation of certain antiviral compounds—was performed on human subjects. The soluble antiviral components were tested for their ability to effectively inhibit influenza virus infection in vitro. Samples were collected and processed following a moderate exercise bout, prolonged exercise bout, and during conditions of psychological stress.