Sure, we’ve heard and read all the comments that we need to drink plenty while we exercise outdoors. However, how much is “plenty”? Well, I decided to do my own little experiment to see just how much fluids I was expending during my rides.
What I did (and I highly recommend you do this, too) is get on the scale first thing (sans clothes and after using the toilet). Then when I was done riding and came home, I did the same thing. I disrobed, emptied myself, and got on the scale. I took mental notes of all the fluids and snacks/foods I had consumed during the interim. Wow, was I ever surprised at the final numbers. So, here goes.
Exhibit A: Nasty Hill Ride, Memorial Day. 25 miles.
When we were done, it was very humid, and temp was in the low 80’s.
Here’s what I consumed in b/t rising and then weighing myself after the ride:
(a) Morning smoothie – 24oz
(c) 2 – 24oz hydration drinks during ride
(d) few bites of snack bar
(e) 10 oz recovery drink when done
(f) ~8oz (or more) of water on way home
(g) 2 blueberry pancakes with maple syrup, etc.
(h) Another ~8oz water
Approximate Total of Fluids 98oz + ~1lb of food = 7+lbs over all
Now, what was the difference in my weight after riding (and consuming all this)? The verdict: only a 1/2 pound more than I was in the morning. That means, I sweat, exhaled, & otherwise released 6.5lbs of fluids. SIX AND A HALF POUNDS!
Exhibit B – Another Hilly ride – Mid June. 43 miles. By ride’s end – sunny, hot, muggy, mid-80’s.
Rough estimations put my fluid and food intake at over 8lbs.
What was the difference in my weight after riding? I was the same weight as I was that morning when I woke up. So, I let go of 8lbs of fluids during (and after) the ride! EIGHT POUNDS!
What’s the point here? Obviously, it is that I need to drink more than I ever thought. Clearly, the “old standby” rule of drinking a 16oz bottle for every hour of exertion is WAY OFF. Even my own rule of consuming 20-24oz per hour has not been enough. In fact, I’ve done some more research and learned that: (a) we have the ability to sweat 1 liter…and up to 2 liters of fluids under really stressful conditions in one hour; and (b) we’re only able to absorb about a liter of fluids per hour. That means, you’re able to put yourself into a nasty deficit–if you’re not paying attention–very quickly. The rides about which I wrote above were hot, but not nearly as hot as what we get here in the height of mid-summer in Georgia. In addition, the temperatures this year have been well above normal. If you’ve read my post elsewhere, you know that I did a 70 mile ride this past Saturday. When we were done, the heat index was 107 degrees. Blazing hot is an understatement!! ::bleah:: We were covered in a thick layer of sweat at all times. At the convenience stores where we stopped along the way for refueling, we tried to wipe away some of that sweat only to find that our bodies instantly released another layer of perspiration. Within seconds, the perspiration was as thick as it was before we wiped.
What does this mean for you? I’d venture to guess that your body isn’t all that different from mine and that you’re losing far more fluids than you ever thought, too. Again, I challenge you to do what I did – take readings from your scale before and after your rides. If it’s humid, drink even more than you normally do. Your body really kicks up the sweat output in an effort to cool you. However in the humidity, the sweat does nothing but drip off you b/c it will not and can not evaporate. (Of course as you already know, evaporation is your cooling mechanism.)
There’s a few of us (me included) who sometimes get headaches after riding. What I realize now is that these headaches were coming from the dehydration of riding (and not from riding position as I had previously thought).
Furthermore, I’ve noticed in the past that I would switch on a “lumberjack” appetite after long or hard rides. Well, no wonder!! You see, the body turns on the hunger signals many times when it is really thirsty. You might think this is odd. However, we still have ancient programming in our genes. (In ancient times, there was no running water. Humans didn’t open a faucet in order to drink. In most cases, humans got most of your hydration from what was eaten. That programming still runs the show: the body sends the signal to eat – hoping to get what it needs in terms of hydration. Btw, keep this in mind when you’re trying to lose weight, too.)
Since then (and particularly after this past Saturday’s ride), I drink as much as I can w/o putting myself into discomfort from an over-full stomach. What has happened? My appetite has been greatly reduced. Sure, I eat a tad more than I do on non-riding days, but my appetite is nowhere near the eating-it-if-it-isn’t-nailed-down type I’ve experienced in the past.
Finally, I have one more thing to add. I have one of those scales that’s supposed to tell you what your body fat percentage is. I’ve realized over the years that this is not the case. What I have noticed is it does tell me differences in the fluids in the body. Noting the percentages before and after rides, I’ve come to realize that it sometimes takes me an extra day to fully replenish my fluids. I’ve come to appreciate just how important it is to consume plenty of water before rides…and not just in the couple of hours prior to the ride but in the day prior to my ride – particularly if it is going to be a long or really strenuous time in the saddle. Granted on this one point, I’m still a work in progress. However with regards to drinking after my rides, I’ve greatly improved. As a result, the after-ride-headaches are quickly becoming a thing of the past.
Bottom line: DRINK. MORE. FLUIDS. Not just during your rides…BUT BEFORE YOUR RIDES, TOO.
…and if you get around to doing your own hydration experiments, post your findings, too!