What about after exercise?
Generally you should drink 16-24 oz of fluid for every pound of weight lost during exercise (450-675mL/lb). Weigh yourself before and after several workouts to get an idea how much weight you typically lose. This will also help you adjust your fluid intake before and during workouts to prevent excessive fluid losses and maintain body water balance. If it’s a really hot day, you’re likely to lose more fluid in sweat, so adjust upward. Salty snacks or meals can help replace sodium losses in sweat.
Your muscles will recover more quickly when you take in carbohydrate (and some protein) after exercise. Carbohydrate is necessary to replace depleted muscle glycogen (fuel for energy). Carbohydrate intake of 0.5-0.7g per pound of body weight is recommended during the first 30 minutes after exercise and again every two hours for 4-6 hours to replace glycogen stores. Protein provides the amino acids necessary for muscle repair. This can be done through food or in your rehydration beverage. Focus on carbohydrate foods with some protein thrown in. Try chocolate milk or flavored yogurt.