Recently I had to take a 2 month break from cycling, and I'm getting back into it now. Last year I was pretty erratic, but averaged about 4-5 hours of riding a week. I've done more in the past (topping out at ~10 hours a week in summer 2008). I'd like to ride at least 10 hours a week, and did just that last week (mostly zone 2/3). Took Monday off, but I felt a bit sluggish on today's ride. Could've just been because it was in the 40s and raining though. I'm not too sore (mostly just hamstrings and adductors (stupid fit issue)), but it felt hard to get my HR and, to a lesser extent, cadence up.
Is 10 easy hours a week too much too soon? I have lots of free time and I'd like to take advantage of it, but at the same time I don't want to overdo it and injure myself or have to take more than a day off from riding every week.