During a triathlon in Florida Teresa McCoy, who is a nurse at a cardiac lab, stopped to help a fellow competitor who collapsed during the race. Police officers thought he had a seizure, but McCoy realized that he didn't have a pulse and started CPR. She asked for a defibrillator from the officers' trunk, and after she shocked him he came to. Once the ambulance came, McCoy got back on her bike and finished the race. The man had a heart attack, and is expected to recover.

Image via max blain/Shutterstock.