Day Hiker wrote:John Duffield wrote: I expect to sweat about a litre and exhale another half litre.
How do you know or figure that 2:1 ratio?
The total amount sounds right, based only on my personal experience.
But of course I had no way to know how much was in sweat and how much was exhaled. I just knew what the scale consistently told me before and after.
Your 13.1 is a lot longer, but maybe (hopefully, for my ego) you don't run it as hard as I ran my 3.2.
And it's probable that your body weight is considerably less than my 215 to 220 when I was running some years back.
It's the ratio we used in Bikram Yoga. Though there the water would go out a lot faster. It takes about two hours for your body to process the water. So you have to go into the activity with your body completely hydrated. In running, I find it best to retain the water. So I tend to dress in order to retain it.