I'm wondering if there's benefits to training when I'm tired. I ride about 10 hours a week - 3-4 hours on Tuesday and Thursday, then about that length or longer on Saturday and/or Sunday. Where I live it's pretty much all big hills. I'm training for a race that's 20 km uphill, and its podunk enough that I just might win. I find that if I ride two days in a row, the second day sucks. I'm slower, my mood isn't great, and I have to eat more during the ride. I'm good about keeping hydrated and having healthy stuff. I pretty much go by how hungry I am and don't load up on carbs after or before a workout because I don't have any idea how many calories I'm burning. Anyways, is getting on the bike the second day and pounding out some miles a waste of time or is it going to make a difference in my fitness level?