So in my current training cycle for Steamtown and the Harrisburg marathon this fall, i’ve found that I need to find a way to not dehydrate myself on my long run. Fortunately I was smart today and had plenty of water, and prepare before and after for the 10 miler. I found that I completed it quite easily when hydrated properly, plus keep in mind that it was cooler this morning than yesterday as well.

I found that my perceptions on dehydration and how much to drink on a run have been totally wrong all along … here are some facts that I, and anyone reading, should keep in mind when running in the heat of the summer. First, the preperation before the workout is important, which i’ve known all along, but I didn’t realize that I can’t just take and slam a gallon of water before the workout and think i’m hydrated. That just won’t work. I guess your tissues need time to absorb the water, and when you have to use the bathroom shortly after drinking it, it means your body didn’t absorb it all, so drink more. I guess there is a fine line to know when enough is enough, but from most of what i’ve read, start drinking water two hours before the workout if possible to prevent dehydration from the start.

Second tip, during the run, your body only processes 6-7 oz. of fluid every 15-20 minutes, so drinking large amounts of water on the your run (like I do, a 20oz water?) isn’t necessarily doing a lot of good.

Third tip, on a hot day, your body tends to lose 4-5 lbs of water each hour … WOW, thats more than I thought, much more. But based on tip two, you’re body will only process 24-28oz of water per hour (just under 2 lbs), so on a hot day, you will be somewhat dehydrated regardless of how much water you take with you.

So in looking back at a 3 hour run yesterday, I can assume that I took in 42 oz. of water, plus 8 oz of gatorade, so 50oz of fluid total. I potentially lost 12-15lbs of water (really?) during the run … which means that even being optimistic, I was deficient by 8lbs of water during the run, NO WONDER I FELT LIKE CRAP. I realize that these numbers are all averages, and that by the second and third hour, you may not fully lose 4 lbs of water, but in an ideal world, there was NO way I had enough fluids in me to complete my run.

I did a much better job today, and intend to use this knowledge I read from the ‘pros’ to better manage these HOT summer days. My 10-miler today left me craving more, I took fluids well before the run, had 24 oz of fluid with me and ran an hour and a half. I felt good, and stayed hydrated … it was also beneficial that it was cooler today than yesterday, which is a good thing … I would say that after a crappy run yesterday, I made it up today with a strong run.