Download Runners Nutrition Part 2 By Jay Stephenson

Runners Nutrition Part 2
By Jay Stephenson
References:
“Exercise Physiology,” Powers and Howley 331
“Better Training for Distance Runners,” Martin and Coe
The first step to “Good” Nutrition is focusing on what foods you need for optimal
performance instead of focusing on what foods to avoid. The common assumption that
American endurance athletes make is that if they avoid the foods that could harm
performance that they will inherently gain the foods that will improve performance. This
assumption is flawed for many reasons. One example is the common avoidance of
saturated fats by many endurance athletes that has lead to a depletion of iron stores as a
result of avoiding the consumption of red meats.
To learn what an endurance athlete needs to eat in order to maximize performance we
will focus on two primary objectives in the form of questions:
1. What am I consuming?
2. Why should I consume it?
1. What am I consuming? NUTRIENTSThere are six classes of nutrients: water, vitamins, minerals, carbohydrates, fats, and
proteins. In the following sections each nutrient will be described briefly and the primary
food sources of each will be identified. Also within each section, a brief suggestion of
when to consume each nutrient will be given.
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include everything above this line in each of the blog series from #2 on
1. What am I consuming? WATERThe body is 50% to 75% water, depending on age and body fatness. A loss of only 3% to
4% of body water aversely affects aerobic performance. Water is lost primarily through
sweat, urine, respiration, and cell activity.
2. Why should I consume it? WATERDeena Kastor, the American record holder in the marathon, says that one of the keys to
her performance is drinking 1 Gallon of water per day. Optimal consumption of water
comes within 30min after training sessions are completed and during training sessions of
over 1hr 30min. You will often hear a recommended amount of ounces per distance or
time. The troubles with these formulas are that often athletes do not take the time to
remember the amount or timing of such formulas. Also, in December because of the
temperature being cooler you will need less water than in August when it is hot. I
suggest that you drink within 30min after your training session until you are no longer
thirsty and then drink a little more. Think of it in terms of drinking the amount of water
you lost plus a little more for cell adaptation to occur.
Runners Nutrition Part 3
By Jay Stephenson
1. What am I consuming? VitaminsVitamins are needed in small amounts and are not “used up” in the metabolic reactions.
However they are degraded like any biological molecule and must be replaced on a
regular basis to maintain body stores. Vitamins exist in two forms: Fat-Soluble and
Water-Soluble. Vitamins taken in excess can lead to toxicity.
Fat-Soluble vitamins include A, D, E and K. These vitamins can be stored in large
quantities in the body; thus a deficiency state takes longer to develop than for watersoluble vitamins.
Water-Soluble vitamins include C, the B vitamins: thiamin (B-1), riboflavin (B-2),
niacin, pyridoxine (B-6), folic acid, B-12, pantothenic acid, and biotin. Most are
involved in energy metabolism. Vitamin C is involved in the maintenance of bone,
cartilage, and connective tissue.
2. Why should I consume it? VitaminsThe most important vitamins for elite endurance athletes are Vitamin C found in citrus
fruits, strawberries, broccoli, greens (Vitamin C helps with connective tissue synthesis,
hormone synthesis, and neurotransmitter synthesis), Vitamin B-12 found in animal foods,
oysters, and clams (B-12 helps with folate metabolism and nerve function), Thiamin
found in sunflower seeds, pork, whole and enriched grains, dried beans, peas, brewers
yeast (Thiamin is involved in carbohydrate metabolism and nerve function), Riboflavin
found in milk, mushrooms, spinach, liver, enriched grains (Riboflavin is involved in
energy metabolism), Niacin found in mushrooms, bran, tuna, salmon, chicken, beef, liver,
peanuts, enriched grains), Pantothenic acid found in mushrooms, liver, broccoli, eggs
(Pantothenic acid is involved in energy metabolism, fat synthesis, fat breakdown), Biotin
found in cheese, egg yolks, cauliflower, peanut butter, liver (Biotin is involved in glucose
production and fat synthesis) Vitamin B-6 found in animal protein foods, spinach,
broccoli, bananas, salmon, sunflower seeds (Vitamin B-6 is involved in protein
metabolism, neurotransmitter synthesis, hemoglobin synthesis), Vitamin D found in
fortified milk, fish oils, and breakfast cereals (Vitamin D facilitates absorption of calcium
and phosphorus and maintains optimal calcification of bone), Vitamin K found in green
vegetables and liver (Vitamin K help form prothromibin and other factors for blood
clotting and contribute to bon metabolism).
Runners Nutrition Part 4
By Jay Stephenson
1. What am I consuming? MineralsMinerals are the chemical elements other than carbon, hydrogen, oxygen, and nitrogen,
associated with the structure of the body. There are many minerals the body needs but
calcium, iron, and sodium seem to be the most relevant in terms of deficiencies and
toxicity. Like vitamins some minerals taken in excess can be toxic (iron, zinc).
Calcium-(Ca++) and phosphorus combine with organic molecules to form the teeth and
bones. The bones are a “store” of calcium that helps to maintain the plasma Ca++
concentration when dietary intake is inadequate. Bone is constantly turning over its
calcium and phosphorus, so diet must replace what is lost. If the diet is deficient in
calcium for a long period of time, loss of bone, osteoporosis, or stress fracture can occur.
2. Why should I consume it? MineralsIron- Of all substances in metabolism that contribute to the beneficial adaptations seen
with endurance training, a powerful case could be made for iron as the most critical for at
least four reasons:
1. Hemoglobin fills about one third the volume of each red blood cell, so an
increase in red cell mass results in an increased total hemoglobin. Without
iron, hemoglobin cannot be manufactured. An increase in cell mass means
that the rate of production of red blood cells must be stepped up in endurancetrained athletes. In untrained people, typical dynamics of the red blood cell
synthesis-breakdown continuum are such that about 233million cells are
released from the bone marrow into the blood stream each second, with an
equal number destroyed (Cronkite 1973). This number is larger in trained
athletes because of an increased production of cells to meet the increased
destruction of cells.
2. A red blood cell has no nucleus and thus divides no further, but all its
precursor cells do and this cellular division requires DNA synthesis, which is
impossible without iron
3. Endurance training is characterized among other things by an increased
myoglobin content in skeletal muscle. Myoglobin contains iron; limitations in
iron supply should reduce its availability as an oxygen storage reservoir in
skeletal muscle.
4. Krebs cycle enzymes, more than half of which contain iron, which allow
eventual interaction of 02 and H+ to form H20, completing the large-scale
energy release to form FUEL BREAKDOWN (eg energy)(“Better Training
For Distance Runners”, Martin and Coe).
Runners Nutrition Part 5
By Jay Stephenson
1. What am I consuming? CarbohydratesCarbohydrates can be divided into two classes, those that can be digested and
metabolized for energy (sugars and starches), and those that are indigestible (fiber). The
sugars are found in jellies, jams, fruits, soft drinks, honey, syrups, and milk while the
starches are found in cereals, flour, potatoes and other vegetables. Fiber is found in
vegetables, various fruits, breads, cereals, pasta, and rice.
Sugars and starchesCarbohydrate is a major energy source for all tissues and crucial source for two: red
blood cells and neurons. The red blood cells depend exclusively on anaerobic gylcolysis
for energy, and the nervous system functions well only on carbohydrate. Carbohydrates
exist in three forms: mononsaccharides, disaccharides and polysaccharides.
Monosaccharides are simple sugars and are found in fruits, honey, sports drinks, etc.
Disaccharides are formed by combining two monosaccharide. For example, table sugar
is called sucrose and is composed of glucose and fructose. Sucrose is the most common
disaccharide and is found in cane sugar, beets, honey, sports drinks, and maple syrup.
Polysaccharides are complex carbohydrates that contain three or more monosaccharides.
Polysaccharides can contain anywhere from three monosaccharides to several hundred.
The most usable form of polysaccharide is found in starch from corn, grains, beans ,
potatoes, and peas. After ingestion starch is broken down to form monosaccharides and
may be used as energy immediately by cells or stored in another form within cells for
future energy needs. Glycogen is the term used for the polysaccharide stored in animal
tissue. It is synthesized within cells by linking glucose molecules together. Glycogen
molecules are generally large and can consist of hundreds to thousands of glucose
molecules. Cells store glycogen as a means of supplying carbohydrates as an energy
source.
2. Why should I consume it? CarbohydratesDuring exercise individual muscle cells break down glycogen into glucose
(glycogenolysis) and use it as a source of energy for contraction. This also occurs in the
liver as glucose is released into the blood stream. Glycogen is stored in the muscle fibers
and in the liver. Total glycogen stores are relatively small and can be depleted in a few
hours of prolonged running. Therefore, glycogen synthesis is an ongoing process within
cells. Diets low in carbohydrates tend to hamper glycogen synthesis, while highcarbohydrate diets enhance glycogen synthesis. Insufficient glycogen stores will result in
a decrease in energy efficiency and eventually energy depletion and a loss of willingness
of the athlete to continue exercise. Replenishing carbohydrates within a 30 min window
after to depletion will allow for super-carbohydrate-absorption. After this 30 min
window absorption ability begins to decrease.
Runners Nutrition Part 6
By Jay Stephenson
1. What am I consuming? FatsFats are essential for energy production, absorption of fat-soluble vitamins, cell
membrane structure, hormone synthesis, insulation, and the protection of vital organs.
We will discuss the two categories of fats in terms of their cholesterol concentration.
Low-density lipoproteins (LDL) carry more cholesterol than high-density lipoproteins
(HDL). High levels of LDL cholesterol are directly related to cardiovascular risk while
high levels of HDL cholesterol offer protection from heart disease. The concentration of
HDL cholesterol is influenced by heredity, gender, exercise, and diet. Diets high in
saturated fats increase LDL cholesterol. A reduction in the sources of saturated fats
including meats, animal fat, palm oil, coconut oil, hydrogenated shortenings, whole milk,
cream, butter, ice cream, and cheese will reduce LDL cholesterol.
2. Why should I consume it? FatsCurrent dietary practices for elite runners in many parts of the world, as well as for much
of American society, emphasize low saturated fats and cholesterol, which imply a
minimum of red meat intake, and a greater emphasis on vegetable protein and complex
carbohydrates. For athletes scheduling two training sessions per day and who require a
high-energy intake that can be assimilated easily and quickly, such emphasis is useful.
However, this diet is likely to have a lowered iron content among other essential vitamins
and minerals. Including a reduction of the muscle repairing nutrient, protein.
For endurance athletes animal foods are essential. It is easy to find several sources of
animal foods without high fat content. Lean red meat, poultry, pork, liver, milk, ostrich,
turkey, and fish are excellent sources of the nutrients needed for endurance athletes.
Runners Nutrition Part 7
By Jay Stephenson
1. What am I consuming? ProteinProtein contains 9 essential amino acids, without which the body cannot synthesize all the
proteins needed for tissues, enzymes, and hormones. The quality of protein in a diet is
based on how well these essential amino acids are represented. In terms of quality, the
best sources of protein are eggs, milk, and fish, with good sources being meat, poultry,
cheese, and soybeans. Fair sources include grains, vegetables, seeds, and nuts, and other
legumes.
2. Why should I consume it? ProteinDepending on the point in the training program athletes may require more protein. For
endurance athletes during adaptation to new or increasingly strenuous exercise (e.g. after
a hard workout) protein requirements will be higher.
There is a small concern about consuming too much protein in large doses of individual
amino acid supplements but not from consuming animal foods.
Conclusion:
Strive to get what you need for your body to operate optimally. Use this guide.
Remember that a loss of 3%-4% of WATER aversely effects aerobic performance so you
must replenish it, VITAMINS are necessary for cell activity, IRON must be present for
adaptation, CARBOHYDRATES help energize your body in prep for performance,
FATS are essential for energy production and iron absorption, and PROTEIN allows
your body to reap the benefits of exercise by rebuilding your muscle tissue.