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?

You don't give enough specific information to permit a definitive answer. However, what I understand from your post is that you are riding three times each week' that each ride is 2-4 hours, and (I'm guessing, here) you go pretty hard very time.

If that is right, then I'm not surprised you don't perform as well when riding two successive days. Recovery is important if you are to maximise the benefit of your training, and it will probably take more than 24 hours to recover from a hard three-hour ride in the hills. There are benefits, I believe, to going very hard for several successive days and then resting for several, your body "supercompensates" for the increased stress, but it isn't a strategy to play around with if you don't know exactly what you're doing. I don't, so I don't do it.

I'd probably recommend some more variety in your training, some easier days and some shorter but maximally intensive stuff. In particular, training as specifically as possible for the race by making one of your weekly sessions a full-on blast for 20km over the sort of gradient you'll encounter on the day. But frankly, if you're riding ten hours a week in the hills spread over three sessions, and pushing yourself each time, I'd say you were probably doing OK.

You should be able to do back to back days of threshold work which is what you would be getting on long hills if you were going hard. I suspect your problem is nutrition related. If you're doing a 3-4 hr ride with some intensity you will definitely need to pay attention to replenishing your glycogen stores if you want to workout again the next day.

Start by eating/drinking about 250 Cals/hr of carbs on your rides. For guidance, you're probably burning somewhere between 600-800 Cals/hr on the bike. Some of your energy will come from fat stores, but without knowing your intensity, it's very difficult to determine how many carbs vs fats you are burning. If you want to ride hard the next day, just assume all calories burned were carbs.

Assuming you start with roughly 2000 Cals of glycogen available a hard 4 hr ride could easily exhaust all your glycogen so you would need to eat at least 2000 Cals of carbs after the ride. Pay attention to eating something immediately after the ride as your body will assimilate carbs faster during this period.

You will need to experiment a little to figure out what you need. Initially, I would try more carbs than you think you need and see if that helps.

Not enough info. Overtraining could result from, overtraining or training under less than perfect conditions ie rest and nutrition. Listen to your body, develop the plan that will work and good luck.

Greg's right. Most important thing is eating during the ride: don't get depleted in the first place. Second is carb replenishment after the ride. You're training for a race, but don't give us any idea how strong you are. However, you might assume that eating at Greg's suggested rate will replenish about half your calories. So that's your starting point. You want to eat pretty much pure carbs with a little protein during a ride, and then eat carb heavy after it too, including a little protein and fat. You can buy recovery drink powder for a good start. Read the label and then make your own if you don't want the expense. After maybe 300 calories of recovery drink, eat a good balanced, but carb heavy meal. Vegetables can also be carbs.

I rode a hard 66 miles in the rain on my single yesterday, and then today rode another 50 on our tandem. My legs felt tired when we started today, but we had plenty of go and were able to do high cadence hill accelerations, so I had something in the tank again. Yesterday, I ate 300 cal. for breakfast, 750 cal. on the course and recovery drinks and food for about a 1600 calorie total before dinner. Today I ate 400 for breakfast, 500 on the course and recovery drink and sandwich for about 1300 calorie total before dinner. I should lose a little weight at those rates. If you eat carb heavy, your weight is how you tell if you're eating enough to keep your power up in the long term. If you're also trying to drop weight but want to ride fast, don't drop more than a pound a week.

^^^^^
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