Overview: Male, age 30. Was hitting 55 mpw w/ 2 workouts a week ~14 months ago. Performance gradually declined. At some point I started feeling sick with a malaise that felt a lot like the aftermath of the flu. I felt weak. Running even a few minutes would leave me completely exhausted. I rested (no exercise) 5-6 weeks. Started running again, but felt the malaise come back after a few weeks.
The cycle has repeated itself several times. I will rest 4-6 weeks with no exercise. Start exercising again (very gradually), feel great for a few weeks, then all of a sudden just crash, and this malaise will come back and wipe me out. For reference, during the last "cycle" I peaked at 9 miles in a week before having to abort.
Blood work and multiple doctors have ruled out everything but overtraining, but I have my doubts. It's been well over a year since I was training hard, but somehow I'm still feeling the effects. What could be going on? Has anyone out there experienced anything similar? The cyclical nature makes me think it could be some vitamin/mineral deficiency, but no signs of anemia or iron deficiency.
Notes:
1) Have ruled out most other possibilities (lyme, anemia, etc). Blood work to date has been perfect, everything well within normal ranges.
2) I had ferritin tested twice and both times it was > 70.
3) I'm working with a sports nutritionist and have been watching my diet very closely.