I started running again this week to prep for entering the military. My problem is that when I run I begin to taste copper when I exhale about the same time I start becoming tired. Soon my body feels fine, but I taste copper and my lungs will soon begin to ache, and then I'll feel like I need to stop running.
For reference if it helps, the copper taste stays with me afterwards when I breathe deep for the remainder of the evening, usually disappearing the next morning until I try running again. I get about .5 miles before this happens though. My heart rate is around 150 - 165bpm (beats per minute) when I'm running like this as well.