If you start feeling sick, it becomes tricky to decide whether it's appropriate to rest at home or continue training and competing. For guidance on handling sickness as an athlete, we spoke to Polly de Mille, RN, CEP-ACSM, CSCS, a registered nurse and clinical exercise physiologist and a VIS Expert™, to learn which symptoms are okay to train with and which are warning signs that necessitate rest.  De Mille says listening to our bodies is most important when questioning one’s phy...