Written by guest blogger and student Diana Dickinson – you can visit her blog, which she posts on regularly, HERE.
Every agility competitor I know worries about getting dehydrated when it's hot. We spend all day at a trial, and it gets hot in the sun, or in the arena, and we drink lots of water and encourage our dogs to drink lots of water. Some of us look for salty foods to replace the salt as we sweat. After getting muscle cramps that woke me up during the night after a long weekend's trialing a few year's back, I decided I needed to better understand my body's needs.
Like so many things about agility, it turns out it's not that simple. Drinking water is good, but drinking too much water is bad, and drinking too little water is bad. Both problems can cause muscle cramps, too. Replacing electrolytes (salts) lost through sweat is good, but too much is bad and too little is bad. Balance turns out to be key. Based on everything I've read, drinking too much plain water without also consuming some electrolytes can lead to problems—just like drinking too little water.
The goal of fluid and electrolyte replacement is straightforward: maintain optimum performance with correct levels of electrolytes and water.*
You can tell how much water you need to drink by keeping track of your fluid intake and weighing yourself before and after exercise. If you weigh 150 pounds at the beginning of the day and 148 pounds at noon, and you didn't drink anything (and you were sweating), you lost 2 pounds through sweat (and urine and breathing and other things, but mostly through sweat), which is 2 pounds of liquid you need to replace. “A pint's a pound, the whole world round” (as my mother used to say), so you need two pints of water (a quart). You don't need a gallon, just a quart. And you should be drinking that water steadily all morning, so that you don't lose weight over the course of the morning.
But of course there's a catch. You need to replace the electrolytes lost in sweat as well as the water, or else you can end up with lowered electrolyte levels, which is a problem. You don't need to have a ton of salt, potassium, and magnesium, but you need some. (And, of course, too much isn't good either.) The easiest way to make sure you get what you need is to use an electrolyte replacement drink.
One recipe for homemade electrolyte replacement is this one, from Nancy Clark (sports nutritionist):
1/4 cup sugar
1/4 teaspoon salt
1/4 cup hot water
1/4 cup orange juice (not concentrate) plus 2 tablespoons lemon juice
3 1/2 cups cold water
1. In the bottom of a pitcher, dissolve the sugar and salt in the hot water.
2. Add the juice and the remaining water; chill.
3. Quench that thirst!
Makes 1 quart. per 8-ounce serving: 50 calories, 12 grams carbohydrate, 110 mg sodium.
However, research has also shown that chocolate milk** works for electrolyte replacement and an energy boost. Or water, fruit, and some (salted) pretzels. Both supply all the electrolytes you need. There are also all kinds of fancy commercial products designed to replace electrolytes. They are generally dissolved in water. I like to dissolve Skratch (a commercial powder with some sugar, some electrolytes, and some nice flavors) in iced tea and drink that all day—I like the taste and the slight sweetness, and it doesn't make me feel bogged down. I also keep packages of Sport Beans handy–they're basically salty jelly beans made by Jelly Belly. I find they give me a nice lift at the end of the day—mostly because they're loaded with sugar.
Finally, once you finish the day's trialing, have a nice dinner. You want everything back in balance by the morning.