Most runners have at least one story about how they learned an important lesson about nutrition or hydration the hard way -- through experience. In my running and racing experience, I've eaten too much, eaten too little, not hydrated properly, and eaten the wrong foods. (Don't even get me started on how I know that Fig Newtons before a run are not a good idea!)
Hoping to avoid such problems? Find out about common sports nutrition mistakes and get advice on how to solve them.
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Good article with practical advice. I’d add that refuelling adequately after running will strongly influence the quality of your next run. Within 30 minutes after finishing your run, an optimal refuelling strategy consists of ingesting 0.7g of carbohydrates per lb of body weight, along with some protein. So a 150 lb runner would aim for 105g of carbs. This may seem daunting, but it is easy to attain. A cup of chocolate milk, a bagel, a banana and a cup of sports drink will give you over 110g.