So I had an 18-miler yesterday, and took things quite easy and made sure I was running at a very comfortable steady pace. This turned out to be, as I worked out afterwards, about 9 mins 10 secs per mile. I took on little amounts of water at various points and felt fine throughout.
When I got home, I felt nackered and weak and low on energy so I had a banana, a few jelly babies and about 700ml of water. But about 10 mins later, it all came back up again (sorry if you're eating your lunch!). I didn't feel well at all, still weak, but I tried to eat, but didnt really have an appetite. It was about 2 hours later when I started to feel better and my appetite returned that I had a big meal, and then felt absoultely fine for the rest of the evening.
I'm not sure why this is happening. On the encouraging side, the run itself felt great and I felt I had a lot more to give. It's when I stop running that the problems start. It could be hydration levels. I drank about 300-400ml of water on the run, which doesnt seem a lot to me over 2 hours 45 mins. The problem I have, which prevents me from drinking more, is that I get stiches easily and I could even feel one threatening about mile 16. I can't really think of any other cause. Maybe I need to increase my carb intake, though I felt I had plenty of energy on the run itself and it was only when I got home that I felt wrecked. Has anybody else experienced this?!