If you will not be exercising again for a day or two, you need not worry about rapid refueling. But if you workout hard twice a day, you should consume post-exercise carbohydrates as soon as tolerable.
Ideally 0.5 grams carbohydrate per pound body weight every hour, for 4 to 5 hours (300 calories per hour, if you weigh 150 pounds). Consuming some protein along with the carbs stimulates faster glycogen replacement and optimizes muscular repair and growth.
Some commercial recovery foods tout the benefits of whey protein. Current research indicates no advantage of whey over casein in terms of muscle growth. (Tipton, Med Sci Sports 36(12)2073, 2004) Yes, you can buy commercial recovery foods that contain protein, but you can just as effectively enjoy cereal with milk, bagel with peanut butter or pasta with meat sauce. These foods offer carbs with an accompaniment of protein (a ratio of 40 gm carb, 10 gm pro). If you prefer liquids for recovery foods, choose Instant Breakfast, chocolate milk, Boost, yogurt or fruit smoothies; they are tasty sources of carbs + fluids + a little protein. The trick is to plan ahead and have the right foods and fluids readily available.
Preventing dehydration during exercise is preferable to treating dehydration post-exercise. But if you failed to drink adequately (as indicated by scanty, dark urine), you may need 24 to 48 hours to totally replace this loss. Fruit juices, smoothies and watery fruits are better than plain water because they offer carbs, protein, vitamins and other nutrients that optimize recovery and invest in good health.