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Is there anything sweeter than a sunset run on a breezy summer evening? Unfortunately, this picturesque scenario happens far less often than a tough slog in the hot, humid air with the sun beating on your back. Many runners know how a seasonal uptick in temperature will affect their pace, apparel choices and workout expectations. But have you considered how your fueling routine should shift? During the summer months, modifications in how you fill your tank should be top of mind for every runner hitting the pavement.
Proper fueling in the heat means paying close attention to two the heat means paying close attention to two important things: water and sodium intake. This is because sweat comprises mostly those two things, both of which are vital to everyday bodily functions. Without proper replacement, dehydration can occur, causing early exercise fatigue, lack of coordination, slower reaction times and severe dizziness and delirium.
So how’s a runner to prevent dehydration? Current dietary guidelines suggest that women should consume roughly 2.7 liters of water and 2,300mg of sodium per day. While these are nice guidelines for the everyday individual, fluid and sodium needs are not “one size fits all”—and this is especially true for runners.
A person’s age, size, speed, duration of exercise, acclimatization to temperature and sweat rate play important roles in individual requirements. A sedentary postmenopausal woman needs far less water and sodium than a 20-something female runner. Luckily, there are simple ways for every woman to determine her unique needs.
First, the body’s thirst sensors are unreliable and will not prompt you to drink enough fluid. Do not rely on your thirst level to assess your hydration status. Instead, check your urine color. After a run, a normal output of lightly colored urine (the shade of lemonade) indicates adequate hydration. A small output of darkly colored urine (the color of apple cider) indicates dehydration.
To restore sodium, add a sports drink to runs lasting longer than an hour. Sports drinks are packed with electrolytes, sugar and water. Drinking 8 ounces every 15 to 20 minutes will help replace lost fluids, provide fuel for muscles and replace sodium and potassium lost in sweat.
Another method to assess hydration is to hop on the scale. Weigh yourself before your run, and measure the amount of fluid in your water bottle (always run with a water bottle in the heat). After the run, measure the remaining liquid. Subtract that number from the starting amount to determine how much you drank. Next, weigh yourself again. If your weight is the same as before your run or less than 1 pound off, you are properly hydrated. If you lost more than 1 pound, you are dehydrated.
By using this method, you can calculate your unique sweat rate, which is good to know for future runs. Add the amount you drank to the amount you lost (in ounces). For example, if you lost 1 pound (16 ounces) and you drank 16 ounces, your sweat rate would be: 16 + 16 = 32 ounces. To combat dehydration on runs of similar length and in similar conditions, drink 32 ounces.
Savvy summer fueling doesn’t simply apply to what you do during a run. Eating before and after is just as important. Follow these simple tips to keep your engine revving.
1—Drink enough water throughout the day, especially leading up to a run. Starting a run in a dehydrated state is a lose-lose situation.
2—Eat foods containing water. As a guideline, aim to drink 80 percent of your water and get 20 percent from fruits and vegetables.
3—Don’t shy away from the salt shaker. Eating a little extra salt throughout the day will help prevent dehydration during your run. Grab a salty snack like pretzels, pickles or saltines, or shake some salt on your lunch.
4—Listen to your body. Knowing the signs and symptoms of dehydration, methods for hydration assessment and proper fueling techniques will keep you strong all year long.
Don’t Overdo It
While properly hydrating is extremely important, it’s also important to avoid overhydrating. If your urine is very pale yellow or white, you may have drunk too much water. This may cause a condition called hyponatremia, meaning that salt levels in the body are abnormally (and hazardously) low. Cells cannot function properly without adequate salt, so be mindful of this dangerous condition!
Fit to Be Squares
Hydration doesn’t have to be boring. These simple two-ingredient Watermelon Lime Ice Cubes are a great way to give your water a flavorful boost and stay hydrated throughout the day.
2 cups watermelon
Juice of 1 lime
Place watermelon and lime juice in a food processor or blender, and blend until it’s a liquid consistency. Pour liquid into the ice-cube tray. Freeze for at least 2 hours.