Reading this thread makes me wonder (worry) that I'm also overtraining, and I'd love some input from people who've actually done serious training. Here's my story:
Since March I've been training to do two long rides: The Cape Cod Getaway (75 Sat/75 Sun, June 28-29), followed two weeks later by the STP (100/100, July 12-13). I have been following the STP suggested mileage for my weekend rides and usually the mid-week rides. However, I have also continued doing my 13-mile each way commute by bike during the week, too*. I take Fridays off to rest before the long rides. My weekly mileage for the last few weeks has been in the 200+ range: Usually 100 or 120 miles during the week, plus Sat/Sun mileage, which can be a lot (last weekend: 143 miles).
This seemed to work OK when the training rides were 50 miles/day or less. However, on the 70/70 training rides, I find I'm really worn out during my normal commutes (gee, why could that be? ). I also have noticed I seem to sleep worse after the long rides. More troubling, I barely had a period last month (I'm usually light anyway, but this was next to nothing) and this month looks like it'll be the same way, if I have one at all. My gut feeling is that I'm overtraining, and that I need to back off on my mileage. I'm reluctant to sacrifice my commutes -- I think of myself as a commuter first and foremost, and I do recreational riding on the side , but also I don't know what kind of long-distance mileage to maintain to be ready for my two longer rides later this summer.
Yes, I know I should probably consult a medical professional, but right now I don't have one and can't easily get one. Just gonna do my best on my own, I guess...
*This is complicated: Monday, both ways; Tuesday, one way; Wednesday, both ways or one way + STP-suggested mid-week mileage; Thursday, both ways.