Carbohydrates are important. They are stored as glycogen in your liver and muscles and are released when needed. The glycogen is broken down into glucose in the liver for release to the brain when the brain needs glucose, which is its source of energy.
When you have worked out, especially at an intermediate or advanced level and have not eaten carbohydrates after the workout, you run the risk of bonking when liver glucose levels are down. Bonking looks like: weakness, lightheadedness, confusion and low coordination.
I may have experienced this years ago while on a low-carbohydrate diet. I went out in the middle of July to a house party. I was talking to someone and the next thing I felt was the cold patio cement under my head. I spent the night on a couch with a wool blanket in the 90-degree-heat.
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.