At least that is what I call it. Went for the first 30mi ride on Thursday and a very hilly one. Though I wasn't sore the next day I could tell something good happened. Last night, 2 days later, I'm up every 2 hours going to the bathroom. Finally after the 3rd trip I was reminded of this physical dynamic of the body holding extra water to transport needed glycogen to depleted muscles. When the body sheds the extra water I can wear a path to the bathroom in the night. When trying to cut weight I have noticed a strange increase the next day rather than a weight loss due to water/fluid uptake. Usually this dynamic is not noticeable until I hit the 50mi mark but for this occasion I will blame the hills.
Anyone else notice this? Perhaps have a medical term for this?