After the track season, I took 2 weeks off from running. I was really tired during the last 2 months of the season as well-i.e. heavy legs, tight quads etc. I am currently in my third week back to training, and I still haven't come around. My iron levels, I presume are fine, they were great a month ago and I take an iron supplement. But my legs have been really heavy, and I often feel dizzy. Some days are much better than others. For instance, on Monday I did two runs and felt pretty good, but then on Tuesday, I could barely run 4 miles! Any suggestions? Has anyone else ever experienced this?