Insulin and Carbohydrates
The role of insulin is a current topic reverberating through gyms
everywhere. Insulin is a hormone best known for its
role in glucose metabolism. In an attempt to provide some clear scientific
information to our trainers, this article will discuss the different
classifications of carbohydrates, and how the body regulates blood
glucose levels. Practical applications to bodybuilders will close out the
Carbohydrates provide direct energy for the human brain, central
nervous system, and muscle cells in the form of glucose (blood sugar).
Carbohydrates can be broken down into simple carbohydrates
or complex carbohydrates.
Simple Carbohydrates are sugars, organic compounds whose bonds are
easily broken down by digestion. Sugars are classified as monosaccharides (mono
= one), or disaccharides (di= two). Monosaccharides include glucose, galactose,
and fructose. Disaccharides are two monosaccharide units linked together and
include maltose (two glucose units), sucrose (fructose plus
glucose), and lactose (galactose plus glucose). Your body only has the ability
to absorb monosaccharides into the blood.
Complex carbohydrates are defined as polysaccharides (poly = many) that are
found in starch and fiber. Starches are polysaccharides humans can digest, but
must be broken down into monosaccharides before they can be taken into the
blood. Polysaccharides are either linear (amylose-polymer of 400 to thousands of
glucose) or branched (amlyopectin-polymer containing hundreds of glucose).
Glycogen (stored glucose within the muscle), is similar in structure to
amylopectin, and will be discussed later in bodybuilding applications. Cellulose
is fiber within vegetables which humans are unable to break down and absorb into
How the Body Uses Carbohydrates
The body, after digestion and absorption through the walls of the small
intestines, can put glucose to work in three ways.
It can burn the glucose immediately within mitochondria, releasing carbon
dioxide, water and energy.
If the glucose is not needed immediately, it is converted by the liver or the
muscles into glycogen. Muscle glycogen provides energy only to muscles. Liver
glycogen can supply energy to any part of the body.
Any glucose left over after glycogen saturation is converted to fat by the
liver, and stored in adipose tissue around the body. The degree and pattern of
fat buildup depends on an array of factors, but are primarily linked to whether
a person consistently consumes more calories than are burned through activity.
The body???s natural regulatory system automatically maintains close control over
the level of blood glucose. The body has approximately 20 grams of blood borne
glucose circulating continuously. If blood sugar increases then the pancreas
releases insulin. If this level is too low than glucagon is released.
Monitors blood glucose concentrations
If blood glucose level is too high Insulin is released... If glucose level is too
low Glucagon is released
Fat and muscle cells to Absorb glucose liver to break down glycogen and release
glucose to the blood
thus lowering blood glucose to normal levels thus raising blood glucose to normal
Happens right after a meal Happens between meals
Note: Muscle glycogen does not provide glucose to the blood. Muscle glycogen is
used only by muscle tissue.
It is important for bodybuilders to understand that when insulin levels are high
your body will store excess glucose as bodyweight. Unfortunately, your body does
not care if it is muscle weight or fat weight. It is important to realize the
difference in carbohydrates and their use by muscle tissue. Enzymes within
muscles readily metabolize starch, which is broken down into usable glucose. The
liver has the intermediary enzymes to convert glucose, fructose, galactose,
amino acids, and other metabolites for its glycogen stores. Since your muscles
have the ability to store 250 to 400 grams of glycogen and your liver only has
the ability to store 100 grams of glycogen, it is advisable to keep a high
proportion of your carbohydrate calories from complex
sources. As mentioned
earlier, muscle glycogen is only used by muscle tissue. Since muscle glycogen is
similar to an amylopectin as in starch, it is logical to supply your body with
complex carbohydrates to replenish muscle glycogen stores.
At first glance carbohydrates and insulin can be a confusing topic and if left
to the rhetoric of the average gym can spawn into a deluge of misinformation. We
hope that the article served to clarify some of the confusion surrounding
carbohydrates and insulin.
If you have any questions or comments please contact email@example.com
By Patrick Gamboa B.S.
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