Q: Are sports drinks better than water?
A: Sometimes. "Sports drinks are designed to be taken during exercise that lasts for more than an hour," says Clark. "They are particularly helpful for athletes because they contain a little sugar to fuel the muscles and the brain, as well as a little sodium to enhance fluid absorption and retention."
Q: Are coffee, tea and other caffeinated drinks dehydrating?
A: Absolutely not, says Casa. "They provide fluids just like any beverage. A slightly greater percentage of the ingested fluid may be urinated, but it's still providing water." In fact, "People who are used to drinking caffeinated beverages get accustomed to the caffeine and don't urinate more fluid than they consume via their coffee or tea," adds Clark.
More: How to Avoid Dehydration on Race Day
Q: Is water an effective appetite suppressant?
A: "There's no real evidence. However, people often mistake thirst for hunger, which means you could be eating food when you actually don't even feel the need," advises Clark.
How can you tell the difference? Finish a tall glass of water when you feel a snack attack coming on, and then decide if you still need some food afterward. Nevertheless, extensive research by Barbara Rolls, Ph.D., a professor of nutrition at Penn State, found that eating soup and other liquid-based foods at the beginning of a meal helps reduce hunger.
More: 11 Hydration Strategies for Hot Weather
Q: Is cold water better for your body than water at room temperature?
A: No. "The reasons that cooled liquids (55 degrees Fahrenheit) are recommended for rehydrating--specifically for athletes--are several-fold, including the facts that they empty the stomach faster than room-temperature fluids, cool the body down a little and may increase the willingness to drink," says Rice.
Q: Is it true that you can never get too much water, or any beverage for that matter?
A: According to Rice, you definitely can ingest too much water--resulting in hyponatremia (water intoxication). "This is most commonly seen in marathoners who run so slowly that they don't generate much temperature rise or sweat yet are drinking water excessively," says Rice.
More: How Much Water Should You Drink?
But don't worry. Someone who's healthy couldn't really get to this point, says Valtin. He estimates that it would take almost 15 liters of water for a healthy person to develop hyponatremia.
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