Originally Posted by
Carbonfiberboy
Not overtraining, never thought it was. Get thee to a doctor, see if you can talk the doc into a hormone panel, esp. DHEA or anything else the doc can think of. Of course the usual full panel of blood markers incl. vitamins D and B12 and hematocrit. Tell the doc there's something bad wrong with you and you want a diagnosis. They hate to do that because it's a lot of work, but without a diagnosis there's really nothing to be done. Be persistent. Another thought: heart murmur? Physical exam and EKG? EKG actually pretty quick and cheap. You better have health insurance.
HRV is a diagnostic aid, though no one knows what it's diagnosing, just some unknown problem. Still it's something one can do oneself. Elite HRV for your smartphone works well. You'll need a HR transmitter, either a ANT+ or Bluetooth (Polar or other). You can compare your readings online with those of other Elite users. One has to use it for several days - one reading isn't very meaningful.
I mean no discredit to your thoughts and experiences, because you've been a wealth of knowledge here on the forum, but all of my reading on the subject of overtraining says its evidenced by an increase in heart rate, not suppressed. I'm certainly open, however, to hearing/reading other facts if that is indeed incorrect.
One of the challenges I'm having, in addition to the natural increase in HR due to loss of fitness, is that I've never been in this position before. By that I mean I started riding six years ago and have never taken a break long enough to lose much, if any, fitness, and so I'm unsure if it's to be expected for 20 miles to be challenging after this much time off, or if I should be closer to where I left off. In other words, I may not even know when I'm recovered, because riding at all may taxing at this point.