Warning! Coaching question ahead! No good answers are likely to exist, pubmed isn't helping, etc.
I'm a self-coached male, 28-year-old "perennial" cat 5. I only have the time and opportunity to race 5 or 6 times a year, and I prefer hill climbs and time trials to mass-start events. (This situation on the whole is fine with me, by the way; I'm unaffected by "upgrade fever," and am fundamentally cool with my existence straddling the worlds of racing and recreational riding. And trust me, I ain't sandbagging.)
I LOVE riding my bike, and I train pretty seriously. My peak FT this year was 4.4 w/kg, and I'm probably around 4.3 w/kg at this writing (more from gaining weight than losing FT). My typical CTL is in the range of 90-105 TSS points, and an average week is probably 11-13 hours. Those aren't garbage hours, either; most of the time, I "go hard or go home." Weekly IF's are always over 0.8, and occasionally over 0.9.
My last goal event of 2006 was on October 1st, and I did a good deal better than I had hoped. I'm very, very pleased with my year overall, and it's time to look towards 2007.
On the one hand, I favor RapDaddyo's, "more-is-better/overtraining-is-a-myth" approach on paper. I really do think the term "overtraining" gets thrown around way too much, and it's pretty amazing how much aerobic fitness you can lose with even a short break. (E.g., a 10-day break earlier in the year took me about 6 weeks to fully recover my previous FT.)
On the other hand, I can't help but notice that I've spent much of the last month fighting off various URIs; my sleep quality is suffering; and I'm having a lot of trouble with staying on my diet, as evidenced by my blindingly-rapid addition of about 7 pounds of body weight over the last two months. I see strangers running by outside, and think something like: "Running! Wouldn't a nice RUN hit the spot right now! Too bad I'm too into cycling to ever get any good at running. All that DOMS would realy screw up the 2x20s I'm going to do tomorrow, too. 🙁." Mentally, if nothing else, I feel a need for some sort of a break.
The question is, what sort? I'm torn, so I'm doing what any reasonable person would do: ask a bunch of strangers on the internet! If you were me, would you take a "break" of some sort? If so, of what kind? Keep cycling, but at lower intensity/volume? Mix in some running or something with the cycling, just for fun? Let the bike gather cobwebs while I, like, nordic-ski or something? Real, no-fooling "couch time"? Regardless of the type of break, how would I know the break is over? I'm also very anxious about gaining even more weight during that break, and about the inevitable loss in fitness. While I realize I'll have time to "gain it back" before the season begins, part of me wonders how much forward progress the step backwards will end up costing me. I know a lot of guys who don't make progress season-after-season despite training hard, and I've always sort of suspected it was because they start over from square zero every year.