Preventing dehydration during exercise is preferable to treating dehydration post-exercise. To determine your fluid needs, simply weigh yourself naked before and after an hour of hard exercise during which you drank nothing. The weight loss reflects sweat loss. You can then develop a schedule for drinking adequate fluids during exercise to minimize sweat losses and hasten recovery.
A 2-pound per hour loss equals 32 oz. or 1 quart. This can be prevented by drinking 8 oz. every 15 minutes of exercise.
More: Stay Hydrated With High Water Content Foods
Sodium
When you sweat, you lose some sodium (a part of salt). You are unlikely to deplete your body's sodium supply unless you sweat hard for more than four to six hours. Most athletes easily replace sodium losses within the context of a standard American diet that offers 6 to 12 times the amount of needed salt. But if you eat primarily "all natural" or unprocessed foods, and simultaneously add little or no salt to your meals, you might consume inadequate sodium. This can hinder fluid retention.
Eating salty foods (soup, pretzels, salted crackers, table salt) is an appropriate part of a recovery diet for most healthy athletes. Sports drinks are only a weak source of sodium compared to munching on salty snacks.
More: Are You Eating Too Much Salt?
If you need to rapidly recover to prepare for a second bout of exercise within an hour or two and are worried about digestive problems, consuming a tried-and-true sports drink might be a safe choice. But if you can tolerate food, you'll be able to refuel and rehydrate better with higher-carb fluids (juices) along with salty snacks: crackers, pretzels--whatever else tastes good and digests comfortably.
Foods with a moderate to high Glycemic Index (i.e., sugary sweets, white bread, soft drinks, honey) are among the best choices. They rapidly enter the blood stream and are readily available for fuel.
More: 5 Best Carbs for Athletes
Rest
You aren't "being lazy" if you take a day off after a hard workout; you are investing in your future performance. Your muscles need time (plus adequate carbs and calories) to refuel and heal.
Daily hard exercise optimizes glycogen-depletion, dehydration, needless fatigue and injuries—but not performance!
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