Drinking enough but not too much.

It’s been a strange week or so, I have not been out on a ride since the Easter weekend, not because I‘ve been lazy, just that my training has been in the gym or on the turbo trainer. Last weekend was for rest and recovery and by midday on Sunday I started feeling guilty and getting very twitchy, but I resisted the urge to get on my bike.
I had planned to go down to Truro with John on Thursday and cycle back to Crewkerne about 120 miles on Friday morning, but disappointingly work got in the way, so I have to be content with a local ride instead. It is surprisingly difficult to find new and appropriate routes when the starting point is the same.
I have two 100 mile rides to do this week with a turbo training day in between, after that I have seven rides building up to a 150 miles, totalling almost 1000 miles in May by then I hope to be able to complete the 240 mile challenge in a respectable time.
It’s great that the weather has been improving, but I am slightly concerned about cycling in over twenty degrees, all my training so far has been in cold temperatures so I get by on about half a litre (17 fluid ounces) an hour. The human body has very specific limitations for fluid absorption up to a maximum of about one litre (34 fluid ounces) per hour, but it can loose up to three litres per hour. Surprisingly over hydration is a greater threat than dehydration and getting the balance right over a fifteen hour period will be difficult. What it means is that if after six hours I am excessively dehydrated I will stay that way and will not be able to finish. Over hydration basically flushes sodium from the body in the form of sweat, when blood sodium concentration becomes too dilute, you can develop severe cardiac symptoms leading to collapse a condition called “dilutional hyponatremia” which can be fatal. Nothing serious then!
My plan to make sure I finish and don’t kill myself is two fold firstly experimenting in my training rides by weighing myself before and after each ride and taking a measured amount fluid at regular intervals, secondly is on the day, have a clear idea of what my nutrition and hydration plan is and have a member of my support team make sure I stick to it. All this is very boring but as important as training and all far more complicated than I anticipated when I set myself this challenge. Having said all this, training is going well and so far I have not suffered any ill effects, after my first couple of 100 mile rides I was very fatigued and it took me a day or so to recover, after the last one it only took three or four hours.