On Wednesday, I went for a 24 mile (+/-) ride, my longest one-day ride yet. (I'm getting there, slowly but surely.) The first half was almost trouble free. In fact, I actually made a couple of personal firsts, training-wise.
At roughly the half-way point, I took a rest stop, where I sat on a bench, drank some water, ate some sodium-laced potato chips (I seem to have a problem with low sodium levels, even while not cycling), and went to the rest room.
After I started to continue, every time I came to an uphill climb, I had to stop and take a rest every 500-1000 feet (est.) because my legs were sore. Even short, not too steep climbs were sore on my legs. I was always going uphill in lowest gear for my bike (I forget exactly how much it is, but it's definitely less than 26 gear inches). Whenever I upped my gears on the flats, it was also sore, at least at first (more coasting after that). I was very thankful for the downhill stretches, of course, of which there were a few, including at least one fairly long one.
After I reached my destination, I rested some more, drank some more water (1 liter), and ate some more potato chips and some trail mix I bought at a natural food store there. The trail mix was low sodium, high potassium; which kind of balanced the high sodium chips.
When I got up to catch the bus back home, I walked my bike uphill, and my legs were still sore, if not moreso. After I took the bus back to my home town (about 1hr, 10-15min), I got up to get off the bus, and my legs were still sore.
I ate a chicken fajita burrito (chicken, beans, rice, some veggies, some cheeses), and after I started to leave the restaurant, I realized that my legs were no longer as sore. I figured it must be something in the burrito that I ate that helped me.
My questions: Was it something in the burrito that made my legs less sore? What made them sore in the first place? What should I have eaten at my rest stop to help prevent my sore legs in the first place?
I should mention, that I'm not a racer, just a tourist wannabe. My average speed was 9.1 mph; my normal average is closer to 10 mph.
Thanks in advance for any help, and feel free to add anything extra that's pertinent to this or similar situations.