Carbohydrates
have been receiving a lot of attention in recent years due to the
popularity of Low Carbohydrate Fad diets. The key word being FAD!
Please, just as a note, if any of you or your loved ones are thinking of
doing a low to no carbohydrate diet in the hopes of losing fat, Read
this first!
The following article
will change how many of you look at Carbohydrates. Once you understand
how carbs work in your body, you can maximize energy and yes loose fat
while taking in a fairly high carbohydrate diet.
Carbohydrates are
everything from sugars to pasta and breads. The one thing all
carbohydrates have in common, is they are all composed of one of three
monosaccharides, (Mono = One, Saccharide = Sugar). These three
monosaccharides are Glucose (dextrose), Fructose (levulose or fruit
sugar), and Galactose. All of these three molecules are composed of
Carbon, Hydrogen and Oxygen. They all have different shapes, and these
different shapes give each sugar its unique properties such as taste.
Glucose
- Glucose has a chemical composition of 6 carbons, 12 hydrogen, and 6
Oxygen. This is the only sugar that affects blood sugar. Glucose, when
present in excess in the bloodstream is stored in the muscles as
Glycogen. Glycogen is just a big string of glucose molecules. I'll touch
on this more later on.
Fructose
- Fructose has the same chemical composition of Glucose, however has a
different shape. This different shape means it reacts with your body
differently. Fructose is the sweetest tasting of the three simple
sugars. It is absorbed into the bloodstream, however does not affect
blood sugar levels. Remember that only Glucose affects blood sugar
levels.
Fructose, when absorbed
into the blood is taken to the liver, and broken down into its 6
Carbons, 12 Hydrogen's, and 6 Oxygen's, and re-formed into a glucose
molecule. It is then and only then that the former fructose molecule is
released into the bloodstream. Because it is now in the form of glucose,
it does have an effect on blood sugars, and can be stored in muscle
cells as glycogen.
Galactose - Galactose
again has the same chemical composition of Glucose; however this sugar
is only present in Milk. Galactoses, along with glucose form the sugar
in milk, Lactose, which is a disaccharide.
Disaccharides are two simple sugars bonded together. Like the
monosaccharides, there are three Disaccharides; Sucrose, Lactose, and
Maltose.
Sucrose
= Glucose + Fructose
Lactose
= Glucose + Galactose
Maltose
= Glucose + Glucose
Beyond this there are
numerous combinations of simple sugars. Anything larger than a
disaccharide, but smaller than 6 monosaccharides, is known as an
oligosaccharides. These are only faintly sweet, and are also known as
maltodextrins.
Polysaccharides are
starches. Starches are long chains of sugar molecules joined together
like the beads on a string of pearls. Starch is the plants version of
Glycogen. It is not sweet tasting at all. (Think of a potato.)
Fibers
Dietary fibers are
large carbohydrate molecules containing many different sorts of
monosaccharides. The key difference between fiber and other
carbohydrates is that they are not broken down by the human digestive
system. Fibers will remain unchanged until they reach the large
intestine.
There Are Two Types Of
Fiber:
Soluble
Insoluble
Soluble fibers can be
dissolved in water. (Hence the name) These fibers are beneficial in that
they can slow the speed of digestion due to their thickness.
Insoluble fibers are
such things as cellulose and are insoluble in water. Fruits are an
example of a source of soluble fibers, and vegetables are a source of
insoluble fibers. Insoluble fibers do not affect the speed of digestion.
To absorb the nutrients
from the food we eat, food must be broken down into a form we can absorb
through our intestine walls. The process of digestion starts in the
mouth with an enzyme called amylase. Amylase is present in the saliva
and begins the breakdown of long chain starch molecules into shorter
chain molecules (maltodextrins). This digestion however stops due to the
acids in the stomach.
The stomach acids
denature or destroy amylase. This is where the food swallowed is broken
down further, but only in the physical sense. The food is only broken
into smaller pieces. It is not until these smaller pieces reach the
small intestine where the chemical breakdown continues. This is where
fiber can come into play. As I said above, fiber can delay food from
emptying into the small intestine.
This Has Two Benefits:
Number one, any carbohydrate
digestion to be done in the small intestine is delayed.
Number two; it gives you the feeling
of satiety, or satisfaction from a meal.
In the small intestine,
huge amounts (more than needed) of amylase are secreted and go to work
on breaking down the carbohydrates. This is where speed of absorption
depends on the kind of starch. The larger the molecule, the longer it
will take to break down, and therefore to be absorbed into the blood.
Your body burns
Alcohol, Protein, Carbohydrates and Fat, in that order. Because there is
no place to store alcohol in your system, it is used first. The fuel our
body uses is almost always a mix of carbohydrates and fat. The mixture
depends on your insulin levels.
Insulin
when in the blood stream basically causes your body to store glucose as
glycogen. If insulin levels are low, meaning, you haven't consumed a
meal high in carbohydrates in some time (ex. First thing in the morning)
than the fuel mix is primarily fat. On the other hand, following a large
carbohydrate meal, Insulin levels are high, and the mix is primarily
Carbohydrates.
Insulin also has a role
in the storage of free fatty acids as body fat. So, what we can take
from all of this is that, if we keep our insulin levels low, than we
will end up with a fuel mix of primarily fat. Now, the big question is
HOW do we keep insulin levels lowered?
To answer this question
we must look at the TYPE of carbohydrate. This doesn't mean simple and
complex carbs, as many people still think. This is where we will meet
your new best friend. It's called the Glycemic Index. Get to know each
other; I'll help with the introduction.
The glycemic index is
one of the most important aspects to consider when deciding what
carbohydrates to incorporate into your diet. What it is, is every food
(carbohydrate) is given a rating. This rating is related to its effect
on spiking your blood sugar.
This is important
because when your blood sugar spikes, your pancreas secretes the hormone
insulin to shuttle this glucose from your blood into your body cells.
The glycemic index is based on a base value of glucose. Glucose, which
can be almost immediately absorbed into your blood, is given a value of
100. Values of other foods are based on their comparison to glucose.
For example, if a low
glycemic index carbohydrate is consumed, (for example a Glycemic index
of 70) it means it is absorbed present in the blood about 30% slower
than glucose is. This is important because, with the slower absorption
comes less of an insulin spike.
This, again means, your
body relies more on fat than carbs for everyday energy activities. As
well, the slower the carbohydrate is absorbed, the easier time your body
has of storing it, and the more energy will be stored in your muscle
cells.
If you are looking to loose weight and
keep the carbs in your diet,
the best idea is to consume low to moderate glycemic index
carbohydrates, therefore, avoiding an insulin spike. One disadvantage to
having an insulin spike due to a high glycemic index carbohydrate is
overeating.
Have you ever noticed
when you are at the movies and you have just a small handful of candy,
you are fine for about 10 to 20 minutes, but then you just can't help
but have more. The reason behind this is that when you first consume the
high sugar candy, your body absorbs it and blood sugar levels are
raised. In response to this your body triggers the pancreas to release
insulin.
This insulin spike,
because it is so rapid, is often a little too much. What this means is
your blood sugar levels drop slightly below what they were before eating
the candy. When your body senses the low blood sugar, it releases
hormones which trigger hunger. It is your body's way of controlling the
blood sugar. If insulin levels are too low, it triggers hunger, and you
eat, raising them up, if it is too high, you feel somewhat satisfied,
not eating, giving your body a chance to store the blood sugar as muscle
glycogen.
Remember just because a
food has a low GI value, you must also take into consideration the
amount or grams of carbohydrate being consumed. Here's something to
think about; In Asia, the base of the population's diet is rice and
grains (Carbohydrates, moderate to low glycemic index).
In Asia, obesity is
virtually non existent. Here in North America, where the trend is either
low carbohydrate diets, or an extremely high sugar, high protein diet,
obesity is an epidemic. Now I know that there are a lot more factors to
think about when making a statement like that, but it is something to
think about.
Why has this only
recently become a problem? Why haven't we seen obesity problems in early
years of history? The answer to this is that in previous years, the
population primarily consumed lower glycemic index carbohydrates. There
was no sugar pops, or pop tarts, or frosted flakes. Ask your
grandparents what they ate on a regular basis and I bet the majority of
them had a base diet of low glycemic index carbohydrates.
For
athletes
seeking peak performance in events, (such as a bodybuilder seeking a
kick ass workout) there are times when you need low glycemic index
carbohydrates (such as before a workout) and times when a high glycemic
index carbohydrate is beneficial (immediately after and even during a
workout). It is important to note that for this strategy to work, the
overall consumption of carbohydrates must be high.
(We are assuming this is during a
mass gaining
period for bodybuilders).
As I mentioned before,
carbohydrates are broken down into simple sugars, absorbed into the
blood, and stored in the muscle cells in the form of glycogen. This
glycogen is then broken down as needed to provide energy for working
muscles. If carbohydrate amounts are low, there is not the maximum
storage of glycogen in the body (approximately 500 grams for the average
person).
Not having enough total
carbohydrate consumption will lead to a shortage in energy during
exercise requiring glycogen due to a reduced amount being stored. Simply
put, if you don't provide your body with enough carbs, not enough will
be stored and there will be a shortage during exercise. Almost all
glycogen stores are used up after about two hours of strenuous exercise.
This is called hitting the wall. When all things are equal in a race, or
activity, involving strenuous exercise, it will come down to who has the
highest glycogen stores.
Low GI foods have been proven to extend
endurance when eaten alone one to two hours before an activity.
Scientists compared cyclists performance after eating the same amount of
carbohydrates, one group eating lentils (a low GI food) and the other
eating potatoes (a high GI food). Both groups cycled at the same intensity
however the group that had eaten the lentils was able to maintain this
intensity for 20 minutes longer than the potato group. Several other
studies have confirmed these results.
You may be asking, how
the time to exhaustion of cyclists applies to my workout. Well, it does
and it doesn't. The benefits of consuming a low GI food before a workout
will only be seen in strenuous events lasting around 90 minutes. If you
are in the gym longer than 90 minutes, or as many of you reading this
may be athletes involved in sports such as swimming, soccer, marathons,
or triathlons, using low GI foods will benefit you.
If you are a
bodybuilder, using low GI foods will not directly have an effect on your
workout because your body uses a different energy system to power heavy
lifting (involves primarily creatine phosphate). However, using high GI
foods after your workout will benefit you by replacing lost energy
immediately after a workout.
Another time when using high GI foods
will benefit bodybuilders is when taking creatine.
Because insulin stimulates the storage of energy systems into body
cells, having high insulin levels when taking creatine has been proven
to cause a higher absorption of creatine into muscle cells. This is why
Cell Tech
is creatine mixed with dextrose. (dextrose is another name for glucose,
which has a GI value of 100)
Another benefit to
knowing about the GI is during Carbohydrate Super compensation diets.
Due to the shape of the glycogen molecule, each gram of glycogen is
stored with approximately 3 grams of water. As a result muscle cells
become fuller when packed with glycogen due to the ensuing water
absorption.
When you go through a carbohydrate
depletion phase you increase the amount of GLUT 4 receptors, which are
just simply the receptors that pull glucose into the cell from the
bloodstream. With the increased GLUT 4 receptors, the body is able to
pull more glucose into the cell and store it as glycogen. This "super
compensation"
of glycogen fills the muscle cell with more water than usual, giving
your muscles a fuller look onstage.
Depriving your body of
carbohydrates will force your body to go to muscle and fat as energy.
Depending on what you are doing, your body will go to muscle tissue when
energy is needed immediately, such as High intensity exercise lasting
less than 2-3 minutes.
Lower intensity
activity, basically, walking, will use primarily fat, however, instead
of using carbohydrates as in someone consuming carbohydrates in their
diet, your body is forced to use muscle tissue as the secondary
ingredient in the fuel mix. This translates to a lot of muscle tissue
being broken down to provide energy. More importantly, in low
carbohydrate diets you make up for the lost carbohydrate calories by
increasing your fat and protein intake.
This increased fat
intake can put your cholesterol levels, LDL (low density lipoproteins)
levels up through the roof. All in all this translates to a loss in
muscle tissue and an increased risk of cardiovascular disease.
Here's why:
Your body stores approximately 500 grams of glycogen. When no
carbohydrates are taken in, these stores are used up to supply energy in
the fuel mix. So, just in glycogen, she's lost a half a pound. Good job
Edna! But Wait? remember earlier we learned that each gram of glycogen
is stored with up to five grams of water (I've read everything from 2.3
grams of water/gram of glycogen, to up to five grams of water/gram of
glycogen).
For these purposes
we'll assume it's five grams of water per gram of glycogen. So with the
loss of 500 grams of glycogen goes 2500 grams of water. When Edna stood
on the scale she must have been thrilled to have lost three pounds of
water and glycogen. The additional for would come from a mix of
primarily muscle tissue and a minimal amount of fat.
Conclusion:
With a broad knowledge
of what carbohydrates are and how they work, you can increase
performance, maximize weight loss without loosing the energy, improve
overall health and maximize energy stores. Be smart with what you read.
Exercise and diet is a science and like other sciences it is constantly
changing. Use your brain when reading material.
Check to see if it is
put out by someone who will directly benefit by you following their
advice. And if it sounds too good to be true, it most probably is.
Again, if you have any questions or comments let me know via email with
the subject of 'bodybuilding question'. Until next time, stay big, stay
hard, and remember? IT'S NOT A GAME!
Best of luck,
Ryan
Swan
BSc.
Human Kinetics
BSc. Human Nutrition (2006)
Can Fit Pro Personal Trainer Specialist
CSEP Certified Fitness Consultant
Ryan Swan is a
bodybuilding competitor and author from
Nova Scotia, Canada.
Ryan can be reached at his website at
Carbohydrates
have been receiving a lot of attention in recent years due to the
popularity of Low Carbohydrate Fad diets. The key word being FAD!
Please, just as a note, if any of you or your loved ones are thinking of
doing a low to no carbohydrate diet in the hopes of losing fat, Read
this first! 
