There is no fixed rule on what to eat before, during and after a workout. The below book suggests that, for endurance or intermittent sports exercise of less than 60 minutes duration, you consume 6 - 12 oz of cool fluid every 15 to 20 minutes. However, if you start working out in a fed state, you do not need to eat during exercise of this duration. For exercise of more than 60 minutes duration, the authors suggest to consume 30 to 60 g of carbohydrates in an easily digestible snack or beverage every hour.
At 1 to 4 hours prior to exercise, consume 0.5 to 1.8 g of carbohydrate per lb of body weight, moderate protein and lowfat snack. At 30 to 60 minutes before exercise, consume 0.3 to 0.5 g of carbohydrate per pound of body weight.
For about 30 minutes after exercise, consume 0.7g of carbohydrate per lb of body weight lowfat snack for endurance sports, and 0.7 g of carbohydrate per lb of body weight lowfat snack for intermittent sports. Within two hours after exercise, eat a high carbohydrate, moderate protein and lowfat meal, of 0.5 to 0.7 g of carbohydrate
Some of this information was taken from Winning Sports Nutrition by Linda Houtkooper, PhD, RD, FACSM, Jaclyn Maurer Abbot, PhD, RD and Veronica Mullins, MS, RD, CSCS.
Disclaimer: None of the above information can be taken as a substitute for advice from a medical professional, such as a physician.
My third book, Pocket Guide to Fitness, is available on www.louizapatsis.com, http://www.authorhouse.com, www.bn.com and http://www.amazon.com. If you look up my name on those Web sites, you will find my other books The Boy in a Wheelchair and Life, Work and Play: Poems and Short Stories.