How to Calculate the Expected Sweat Rate on Race Day

Lewis James: The sweat rate that you do calculate from these tests, it's not your rate or the rate or the target in a fixed sense like that. So at my kind of race pace for whatever particular event I'm doing, my sweat rate in this kind of temperature is going to be maybe between 500 and 800 mls an hour. And so I'm working somewhere within that kind of range rather than saying it's 725 mls. Now if you standardize a lot of those things like we can do in the lab, you may see a variance of only kind of 5% or something like that, but outdoors I'd expect to see a much bigger variation than that.