CDC Flu Page
https://templatearchive.com/the-flu-what-to-do-if-you-get-sick/ (opens in a new tab)
Exercise when you have a cold
http://www.webmd.com/cold-and-flu/cold-guide/exercise-when-you-have-cold (opens in a new tab)
Clinical Study of Exercise and Cold Prevention
http://www.ncbi.nlm.nih.gov/pubmed/24921030 (opens in a new tab)