Hi, I used to post on here now and then, but haven't in a long time. I'm 22 and have a history of various arrhythmias and such. Anyways, something that has happened over the course of the past year kind of has me at a loss. I'm a runner, and a very serious runner, so I know exactly what my heart does and does not do in response to all kinds of situations from long runs, to easy runs, to tempos, to VO2 workouts, to racing all kinds of distances in all kinds of weather.