What You Should Know About Summer Hydration Needs

May 03, 2016 Posted By: Bob "Wish" Wischnia

Regardless of where you live or what level of runner you are, proper hydration is one of the most critically important parts of your summer running training routine. Certainly, we all have had the wisdom of drinking plenty of fluids before, during and after summer runs repeated to us ad nauseam, but it can’t be emphasized enough.

Our bodies are mostly water (approximately 70-75 percent) so it’s obvious that hydration is key to maintaining a proper balance of fluids and electrolytes that allow us to run despite summer heat and humidity. (Point of fact, summer doesn’t officially begin until June 20th but my reckoning and the rising temperatures it’s already here in most of the country.)

Here are some FAQ’s (and the answers) about hydrating during summer training and racing:

Q: Why is it so important to stay hydrated during the summer?

A: Proper hydration is necessary year ’round, regardless of where you live and run, but during the heat and humidity of summer, lack of hydration is accentuated and can become life threatening. Staying hydrated is so vital because water supplies nutrients to your body, maintains blood circulation and helps to maintain a comfortable body temp as you run.

The heat you build up during running travels through your bloodstream and eventually goes to your skin. This causes you to sweat which is the body’s way of cooling itself off. This sweat must be replaced by fluids. If you don’t stay hydrated, your blood volume drops which reduces your ability to transfer heat to the skin and forces your heart to beat faster which makes running much more difficult. Even worse, it can lead to serious heat stroke which can be fatal in extreme circumstances.


Q: How much should I drink before a hot summer run?

A: Drink up. Pound at least 10 ounces of water or sports drink before you take off on a summer run. You should drink enough that you have to go to the bathroom before beginning the run.


Q: I carbo-load before long runs and marathons. Can I also water-load?

A: Not really. You aren’t a camel and can’t store water like one. If you drink too much, you merely flush it out by using the bathroom continually before you run. What you can do is make certain you begin the long run or race completely hydrated. But not overhydrated.


Q: In races and long runs, I always see runners dumping cups of water over their heads or running through sprinklers. Is this a good way to stay hydrated and cool off?

A: Nope, it isn’t. Despite what you might think or have heard, dumping a few cups of water over your head on a run does nothing to cool you off or lower your core temperature. Nor does it do anything in terms of hydration. Certainly, wetting the skin by running through a sprinkler or dumping water over your head feels good for a minute, but it simply does not do much to hydrate the body. In fact, some researchers believe that pouring water over yourself during a hot-weather run or race inhibits efficient heat transfer.

Bottom line: The only way to stay hydrated is to drink. There is no substitute. The only way to cool off is to stop running and get in a shaded, area, air conditioned building or jump in a pool, river or lake.


Q: Is thirst a good indication of dehydration?

A: Yes and no. If you’re thirsty, you are already dehydrated and have lost about one percent of your body water. (A two percent water loss and you will begin to experience major fatigue.) Clearly, you can become dehydrated long before you feel thirsty.


Q: How much should I drink while running?

A: Impossible to say because every runner has different hydration needs, based on the actual heat and humidity, your body size, running speed and other factors. Plus, some runners are better in the heat than others. However, on hot-weather runs, planning to drink 6-8 ounces (or more) every 20 minutes or so is a safe bet. In an hour run, plan on drinking at least 2-3 times. Double that on a long run of two hours or more.


Q: How does one keep hydrated on a long, hot summer run?

A: It’s tough. If you are in an organized training group, you’re in luck, as there will usually be water jugs spread out along the long-run courses. That makes it easy. If you aren’t part of a training group, there are several ways to stay hydrated: (1) Bring fluids with you either with a refillable bottle or a hydration belt; (2) cache fluids along the course the night before; (3) fill a cooler with cold drinks and loop around every 20-30 minutes (4) or carry money with you to buy drinks at convenience stores along your run. And one more: Garden hoses. When desperate, you can sneak a drink from someone’s hose or sprinkler. Or in an acute situation, I have stopped cyclists and begged for some of their water they carry on their bikes. Finally, if you want to always be near drinkable water and don’t want to carry it or buy some along the way, plan a route which passes by several water fountains in parks and fields.


Q: I don’t like the taste of any sports drinks. I’ve heard some marathoners used to drink Coke during races. Is this a good idea?

A: No, it is not. Frank Shorter and Bill Rodgers used to drink defizzed Coke during marathons in the ‘70s, but it was for the sugar and caffeine, not for the hydration benefits. At this time, there was not the luxury of sports drinks. If you don’t like sports drinks, taste test a variety to find one that suits your taste buds. If you still don’t like any of them, stick with water.


Q: Which foods are good for rehydration purposes?

A: The best foods for re-hydrating after a run are fruits such as strawberries, oranges, pineapples, blackberries, cantaloupe and peaches. But the absolute best fruit to replenish fluids after a run is with slices of cold watermelon which is practically all water anyway. There is nothing better. In the summer, you should up your fruit and veggie intake to about five cups a day. The more, the better.


Q: Is there anything else that works to stay hydrated?

A: There is one way that you can improve the body’s ability to retain water during a long run or marathon. That’s by using glycerol in your water. Glycerol is a liquid that when properly diluted in water and ingested before running, lowers your urine output, increases your sweat rate (so the body says cooler) and since the body is cooler, lowers the heart rate. Drinking water properly diluted with glycerol can result in a 20 percent improvement. Two problems with using glycerol: Getting the dilution exactly right and the awful taste it brings to water. But it works.




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