Should I Eat Before a Run?

Yes, you should eat about 1 1/2 to 2 hours before you start running. Eating immediately before running may lead to cramping or an upset stomach, whereas running on an empty stomach may cause you to run out of energy. Opt for something high in carbohydrates and lower in fat or fiber which stays in the stomach longer and can cause discomfort. Carbs will give you the energy you need for your run. Some examples of good pre-workout fuel include: a bagel or bread with peanut butter, a lowfat granola bar, a banana or other fruit, a small bowl of cereal, or light yogurt with fruit. And everyone is different so find what works for you!

What Should I Eat After a Run?

After a workout, especially a longer run, you want to replenish energy as quickly as possible. Your body needs to rebuild and replenish glycogen and amino acids (or protein) broken down during exercise. Eating right way will also help to minimize muscle stiffness and soreness as well as aid in muscle and tissue rebuilding and strengthening process. You’ll want to consume primarily carbs, with a smaller amount of protein. A good rule of thumb for post-run eating is a 2:1 or 2 carb to 1 protein ratio. Nutrition bars or protein shakes are healthy options and great if you are unable to eat a meal following your workout. Other examples would be a bagel with peanut butter or a smoothie made with fruit and yogurt.

What about water?

Always make sure that you are well hydrated whether it’s hot or cold outside. It is critical to your performance and to prevent fatigue or even heat related illnesses. Here are some general guidelines taken from about.com:
Hydration Before Exercise
• Drink about 15-20 fl oz, 2-3 hours before exercise
• Drink 8-10 fl oz 10-15 min before exercise

Hydration During Exercise
• Drink 8-10 fl oz every 10-15 min during exercise
• If exercising longer than 90 minutes, drink 8-10 fl oz of a sports drink (with no more than 8 percent carbohydrate) every 15 – 30 minutes.

Hydration After Exercise
• Weigh yourself before and after exercise and replace fluid losses.
• Drink 20-24 fl oz water for every 1 lb lost.

Resources:
running.about.com