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More Spaghetti Please

More Spaghetti Please


Credit: National Cancer Institute
Source: https://commons.wikimedia.org/wiki/File:Pasta_%281%29.jpg
License: CC BY-NC 3.0

Each year, the city of Spokane, WA sponsors a 12k (7.46 mile) race in early May. Approximately 50,000 racers participate by running, walking or being in the wheelchair competition. For several days before the race, local restaurants advertise pasta dishes to help the participants carbo-load so they have that extra energy to draw on as they run up Doomsday Hill at Mile 5 of the race.

News You Can Use

  • Materials consumed by the body are not wasted. When we have that double cheeseburger and a triple order of fries, our bodies will use part of the fats, proteins, and carbohydrates for immediate purposes such as building cells and providing biochemical energy. The remainder is stored until the time we need these chemicals. One obvious consequence of this fact is the weight gain we experience when we have too many of those double cheeseburgers.
  • Starch is a polysaccharide composed of glucose monomers that we consume in our diets (those fries are a prime example). In the small intestine, the starch is digested to release the glucose molecules, which then enter the blood stream and are transported to the cells for use in producing biochemical energy. Excess glucose is stored in the liver and in skeletal muscle in the form of another polysaccharide known as glycogen. The stored glycogen is available for energy when the body needs it.
  • Credit: Raymond Bryson
    Source: http://www.flickr.com/photos/f-oxymoron/9652463930/
    License: CC BY-NC 3.0

    Fries are delicious, but they are full of starch and processed oils. Eat them in moderation, unless you are preparing for a race that is [Figure2]


  • When the blood glucose concentration drops below a certain point (roughly 50-60 mg/dL for most people), the pancreas senses this decrease and releases a chemical called glucagon. This 29-amino acid peptide stimulates a process that leads to the breakdown of glycogen to re-form glucose molecules, providing the starting materials for the synthesis of ATP (biochemical energy).
  • Carbo-loading is a practice employed by distance runners to accumulate glycogen. Excess carbohydrate consumption leads to more stored glycogen, when can then be drawn upon when the body requires extra energy during the race.
  • Watch a video about glycogen metabolism at the link below: https://www.youtube.com/watch?v=rqDGlChGZPk

Show What You Know

Use the links below to learn more about glucose utilization by the body. Then answer the following questions.

  1. What is liver glycogen used for?
  2. How does muscle use glycogen?
  3. What is the enzyme that builds up the glycogen chain during glycogen synthesis?
  4. What are some easy-to digest foods for carbo-loading?
  5. What should be avoided while carbo-loading?

Image Attributions

  1. [1]^ Credit: National Cancer Institute; Source: https://commons.wikimedia.org/wiki/File:Pasta_%281%29.jpg; License: CC BY-NC 3.0
  2. [2]^ Credit: Raymond Bryson; Source: http://www.flickr.com/photos/f-oxymoron/9652463930/; License: CC BY-NC 3.0

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