Download Nutrition Basics

Nutrition Basics
Proper nutrition is the basis of for physical performance; it furnishes both the fuel for bodily work and the chemicals
for extracting and using the potential energy contained within this fuel. Food also provides the necessary elements for
the formation of new tissue and the repair of existing tissue. Carbohydrate, fat, protein, vitamins, minerals and water
are the six major classes of nutrients. When consumed daily, they provide the essential energy to maintain body
functions at rest and during exercise. Energy is supplied by carbohydrate, fat and protein. Carbohydrate and protein
supply approximately half the energy that fat supplies:
Carbohydrate
Protein
Fat
Alcohol
4 calories per gram
4 calories per gram
9 calories per gram
7 calories per gram (not a source of energy)
While normally active adults may require 2000 to 2800 calories for weight maintenance, it is not uncommon to find
athletes in training with daily food intake in excess of 5000 calories. Vitamins, minerals and water are necessary for
tissue growth, maintaining body structure and controlling body processes.
Carbohydrates
Carbohydrate is the major source of fuel for the red blood cells and central nervous system. It saves protein from being
used for energy and assists in the mobilization of fat for energy.
The primary kinds of carbohydrate are sugars and starches, obtained from such foods as fruits, vegetables, breads,
pastas and cereals. They are broken down during digestion into glucose, which the red blood cells and central nervous
system use for energy. Glucose is also the chief fuel source for the muscles during exercise. When glucose is not used
immediately for energy it is stored in the liver as glycogen, which is a long chain form of glucose molecules. Glucose
not used as energy or converted to glycogen is converted to fatty acids and stored as body fat.
Athletes derive the greatest energy for exercise from carbohydrate. During the first few minutes of exercise, glucose is
the major source of fuel. After that the body begins to draw upon its supply of stored glycogen for energy. When these
glycogen stores are depleted, the athlete becomes fatigued.
Heavy exercise or physical training can deplete the body's muscles of most of its stored glycogen. In order to replenish
the muscle glycogen used up training each day, nutritionists suggest eating a diet high in carbohydrate. Generally
speaking, 55-60% of an athlete's total caloric intake should be derived from carbohydrate.
Fat
Fat is a concentrated source of energy in animals as important as carbohydrate is in plants. It supplies essential fatty
acids and carries the fat-soluble vitamins A, D, E and K. During digestion, fat derived from foodstuffs is broken down
into fatty acids. Body cells, except red blood cells and those of the central nervous system, can use fatty acids directly
as a source of fuel. Fatty acids not utilized as energy are stored as body fat.
While carbohydrate is the major fuel source for the athlete, fat may also be utilized. However, it takes 20-30 minutes
from the time the athlete begins exercise until enough fat is available to serve much good during exercise. When the
body begins to burn fat for energy, less glycogen is used. Since there is an abundance of fat stores in the body, this
process is important for athletes involved in prolonged endurance-type activities. The drawback of this process is that
fat is a less efficient energy source than carbohydrate. It takes more than twice as much oxygen per gram for energy to
be released.
The most abundant form of fat in the body is in the form of triglycerides. Triglycerides consist of two components,
fatty acids and glycerol. There are two forms of fatty acid molecules, known as saturated and unsaturated. Saturated
fatty acids are found in prime cuts of meat, poultry skin, shellfish, butter, whole milk products, cocoa butter, coconut
oil, palm oil, palm kernel oil, and hydrogenated fats. Unsaturated fats are generally found in plant sources such as
sunflower, corn, soybean, sesame, cottonseed oils and olives, avocados, peanuts, cashews and their oils. They may also
be found in omega-3 fatty acids found in fish.
Nutritionists suggest that fat constitute approximately 25-30% of a person's total caloric intake, and limiting the amount
of fat calories derived from saturated fatty acids to 10% or less. Although the unsaturated fats can lower cholesterol, it
is recommended that they do not increase total fat intake to greater than 30%.
Protein
Protein is not used as a source of fuel under most circumstances. However, it is essential for building all cells in the
body. Protein is necessary to:
1.
2.
3.
4.
Repair body tissues
Make hemoglobin, which transports oxygen to the tissues
Form antibodies in the bloodstream
Produce enzymes and hormones
Protein is composed of the linkage of many smaller molecules known as amino acids. When protein is consumed and
digested, it is broken down by enzymes into the amino acids from which it was originally built, and used to build
muscle, hemoglobin, enzymes or hormones. Amino acids that are not used in these processes are stored as body fat.
Of the 22 amino acids required by the body, 8 (9 in infants and stressed older adults) cannot be synthesized in the body
and must be provided pre-formed in foods. They are referred as essential amino acids. The remaining amino acids that
can be manufactured within the body are called non-essential amino acids. This does not mean that they are not
important, but rather that they can be synthesized in the body from compounds ordinarily available. Protein nutrients
that contain all of the essential amino acids in the correct form, they are termed complete proteins (higher quality). An
incomplete protein (lower quality) lacks one or more of the essential amino acids. Sources of the complete proteins are
mainly of animal origin (eggs, milk, meat, fish and poultry) whereas most vegetable proteins (lentils, dried beans and
peas, nuts and cereals) are incomplete proteins.
Despite the beliefs of many athletes, there is no benefit from eating excessive amounts of protein. In fact, excessive
protein will lead to storage of fat below the skin and may place great strain on the liver. On the average, a daily intake
of 0.7 to 0.9 g of protein per lb body weight is recommended. This level of dietary consumption generally constitutes
approximately 20% of total caloric intake.
Vitamins
Vitamins are organic substances needed by the body in small amounts. They help control the growth of all body tissues
and are necessary for the release of energy in the body. The body cannot manufacture vitamins; thus, they must be
supplied in the diet or through manufactured supplements.
A well-balanced diet of various meats, cereals, fruits, vegetables and milk will provide a person with a sufficient supply
of vitamins to meet the body's needs. Because vitamins can be used repeatedly in metabolic reactions, the vitamin
needs of athletes are generally no greater than those of sedentary people.
Table 2.1 Water-soluble vitamins, their dietary sources, and major bodily functions
Vitamin
Niacin
Panthotenic Acid
Vitamin B-1 (Thiamine)
Folacin
Vitamin B-6 (Pyridoxine)
Vitamin B-2 (Riboflavin)
Vitamin B-12
Legumes, green vegetables,
whole-wheat products
Biotin
Synthesis and breakdown of
amino acids
Vitamin C
Muscle meats, eggs, dairy
products (not present in plant
foods)
Dietary Sources
Legumes, vegetables, meats
Formation of red blood cells,
RNA, and DNA
Citrus fruits, tomatoes, green
peppers, salad greens
Normal growth, maintenance
of neural tissue, formation of
red blood cells
Pork, organ meats, whole
grains, legumes
Widely distributed in foods
Liver, lean meats, grains,
legumes (can be formed from
tryptophan)
Major Body Functions
Involved in energy metabolism
Meats, vegetables, whole-grain
cereals
Involved in energy metabolism
Widely distributed in foods
Involved in energy metabolism
Involved in energy metabolism
Fat synthesis, amino acid
metabolism, glycogen
formation
Maintains intracellular matrix
of cartilage, bone and dentine;
collagen synthesis
Table 2.2 Fat-soluble vitamins, their dietary sources, and major bodily functions
Vitamin
Vitamin A
Vitamin D
Vitamin E
Vitamin K
Dietary Sources
Body Functions
Beef, liver, carrots, spinach,
eggs, milk
Vision, growth
Eggs, dairy products, fortified
milk, margarine (also from
sunshine)
Bone growth, absorption of
calcium
Seeds, green leafy vegetables,
margarine, shortenings
Protects cell structures
Green leafy vegetables,
vegetable oils
Blood clotting
Minerals
Minerals are needed for maintaining body structure and controlling body processes. They are inorganic elements that
combine with organic compounds in the body. The most important minerals are those found in enzymes, hormones and
vitamins. In the body, minerals are categorized as major minerals - those present in large amounts and have known
biologic functions, and trace minerals - those present in small quantities. A well-balanced diet will supply sufficient
amounts of minerals. An abundance of minerals is worthless to the body and may be hazardous.
Water
Although water does not contribute to the nutrient value of food, it is probably the most neglected nutrient among
athletes. The energy content of foods tends to inversely relate to the amount of water they contain. That is, foods high
in water content are low in calories.
The human body is approximately 60% water. Thus, it is probably the most important substance essential to human
life. In the body, water serves as:
1.
2.
3.
4.
5.
A solvent for digestion, helping the chewing and softening of food
A solvent for the elimination of waste products
A major constituent of blood
A lubricant in the joints, and between internal organs
A coolant for the body
The ability of water to cool the body is extremely important for athletes. During exercise, sweat the evaporation of
sweat produced by the body serves to keep the body from over-heating. The amount of water lost through sweat
depends on the intensity of exercise and the environmental temperature. The relative humidity of the surrounding air
also determines the efficiency of sweating. When relative humidity is high the water vapor in the air inhibits the
evaporation of sweat. The body is more likely to overheat under these conditions. It is essential that athletes drink
sufficient fluids before, during and after exercise. People are usually dehydrated by the time they feel thirsty.
Therefore it is important to drink fluids before you train or compete.
Table 2.3 Important minerals, their dietary sources and major bodily functions
Mineral
Calcium
Milk, cheese, dark-green
vegetables, dried legumes
Bone and tooth formation,
blood clotting, nerve
transmission
Phosphorous
Milk, cheese, meat, poultry,
grains
Bone and tooth formation,
electrolyte balance
Meats, milk, many fruits
Electrolyte balance, body
water balance, nerve function
Common salt, seafood
Electrolyte balance, formation
of gastric juice
Common salt, seafood
Electrolyte balance, body
water balance, nerve function
Whole grains, green leafy
vegetables
Activation of enzymes, protein
synthesis
Eggs, lean meats, legumes,
whole grains, green leafy
vegetables
Formation of hemoglobin and
red blood cells, energy
metabolism
Zinc
Liver, vegetables, milk, egg
yolk
Important for digestion,
growth
Iodine
Dietary Sources
Fish, dairy products,
vegetables
Body Functions
Important for thyroid gland
function
Potassium
Chlorine
Sodium
Magnesium
Iron
Guidelines For The Athlete
Breakfast
Your body and mind both need fuel to achieve maximal performance levels. Muscles need fuel to contract and carry
out the motor skills necessary to your sport. Your brain needs fuel to maintain mental alertness and the ability to make
complex decisions during competition. Without a good breakfast, your body and mind will be like a car running on
fumes by the middle of the day. Start the day with a wholesome breakfast. You will be alert during class and have the
energy for daily workouts. If you are on the run, some quick-fix breakfast ideas include:
1.
2.
3.
4.
5.
6.
7.
8.
yogurt
bananas
blender drinks
raisins and peanuts
bagels
bran muffins
graham crackers
pita bread stuffed with light cheese, cottage cheese, peanut butter, etc
Cereal is a convenient, carbohydrate-rich breakfast staple. Many cereals are excellent sources of fiber and are often
fortified with iron. By adding low-fat milk to cereal you also get a meal rich in calcium and low in cholesterol. Add a
glass of orange juice or eat fruit high in vitamins A and C with cereal to enhance iron absorption. Remember to choose
low-fat, low-salt cereals to maintain a healthy lifestyle.
Caffeine
Athletes often inquire about the reported ability of caffeine to in increase endurance. However, research in this area
has been inconclusive. Moderate amounts of coffee or tea (1-2 cups) are unlikely to harm a healthy person, but there
are substances in coffee and tea can interfere with the absorption of iron. 1 cup of coffee can reduce by 40% absorption
of a hamburger's iron. Additionally, caffeine stimulates gastric juices and may cause "coffee stomach."
Fast Foods
In today's hustle and bustle world, many of us are forced to eat on the run. Unfortunately, we often settle for fast foods
rather than wholesome foods. Fast foods are usually high in fat and generally lack fiber content of wholesome foods.
They may be low in nutrients, especially vitamins A and C, and are often high in salt. Along with these hamburgers,
fried chicken tacos, etc. we also choose sugar-laden soft drinks with zero vitamins and minerals or fat-laden shakes
with limited nutritional benefits. If you must eat at a fast food restaurant, choose foods high in carbohydrates and low
in fat. Ask for an extra bun with a grilled chicken sandwich, for example. Better yet, try to plan ahead and carry
carbohydrate-rich bagels and fruit with you to school for snacking between classes.
Pre-event Nutrition
There are several reasons for having a nutritionally sound pre-event meal:
1.
2.
3.
4.
To help prevent hypoglycemia (low blood sugar), which brings about fatigue in the muscles and reduces
mental alertness
To help settle your stomach; we all know that an anxious stomach can take away from our concentration from
the matters at hand
To fuel the muscles and ensure that you can "go the distance"
To pacify the mind; after having a good pre-game meal you will know that body is well-fueled
Each of us is a different animal and we must each realize what makes us tick. It is important that you determine what
particular food is right for you. However, the following guidelines will ensure that everyone is ready to perform at a
high level:
1.
2.
3.
4.
5.
6.
Choose high-starch, low-fat foods
Avoid sugary foods, which lead to hypoglycemia
Allow adequate time for food to digest
Liquid foods leave stomach faster than solid foods (e.g., blended breakfast)
Eat familiar foods before a competition
Drink plenty of fluids
Recovery Foods
Fluid Replacement
Following a hard workout, game or match it is essential that you replace the fluids lost by sweating. Some of the best
sources replacing sweat losses are:
1.
2.
3.
4.
Juices
Water
Watery foods such as watermelon, grapes, soups
High-carbohydrate sports drinks (supply fluids, but minimal vitamins and minerals)
Examples of watery foods include:
1.
2.
3.
4.
5.
6.
Food
Lettuce
Cucumber
Tomato
Orange
Banana
Chicken
% Water
95%
95%
95%
85%
75%
60%
Compare these foods to the following:
1.
2.
Food
Cheese
Cookie
% Water
35%
5%
Replacement of Fuel Stores
You should consume carbohydrate-rich foods and beverages within 1-4 hours after competition or workout. A good
target intake is 0.5 grams of carbohydrate per pound of body weight within first two hours and same amount two hours
later. For example, a 130-pound person should attempt to attain 130 x 0.5 or 65 grams of carbohydrate (260 calories).
This amount can be easily be achieved with:
1.
2.
3.
4.
1 cup of orange juice and a bagel
2 cups of cranberry juice
1 12-oz can of soft drink (non-diet) and 8 oz of fruit juice
1 bowl of cereal and a banana
Sports drinks such as Gatorade or Exceed have approximately 10 grams of carbohydrate per cup, but they lack the
vitamins and minerals found in wholesome foods.
Electrolytes
In addition to the water lost when you sweat, some minerals (electrolytes) such as potassium and sodium are also lost
from the body. These minerals help your body function normally. Fortunately, these losses can be replaced by
choosing the right recovery foods and fluids after your workout or competition. The following guidelines help to
ensure sound recovery from your event.
Potassium can easily be replaced with the following foods:
1.
2.
3.
4.
Potato
Yogurt
Banana
Orange Juice
750 mg
500 mg
500 mg
420 mg
Sodium
1.
2.
3.
4.
Yogurt
Muffins
Pizza
Spaghetti
While sports drinks replace the fluids lost during workouts or competition and are a source of carbohydrates, they have
little, if any vitamins or minerals. Eight ounces of Gatorade contains only 24 mg of potassium while eight ounces of
Exceed contains only 45 mg of potassium. Thus, a combination of juice and water would provide a fluid replacer that
is quickly absorbed by the body, a greater source of carbohydrate and more vitamins and minerals than commercial
sports drinks
It is also essential that you rest after intense exercise or competition. All the sound nutritional advice in the world will
not help you if you do not allow your muscles and your mind to recover from tough workouts or competition.
Salads
Salads can be a great source of nutrition for the athlete, but they should not be the only things the athlete eats. Sound
nutrition for the athlete includes foods from all four major food groups. A nutritious sports salad should be filled with
colorful, vitamin-rich vegetables, carbohydrates, protein-rich beans, and topped with "lite" dressing.
Snacks
Snacks do not have to be thought of as the "four-letter word" of nutrition. Snacks are simply defined as small meals
and can be of great importance to the athlete. A nutritious mid-morning snack can give you the energy to keep your
mind attentive during class. A sound mid-afternoon snack will provide the energy for your afternoon workout. An
evening snack can give you extra calories if you are trying to gain some weight. The athlete's snacks should be high in
carbohydrate and low in fat. Some examples of snacks for the athlete include:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Dry cereal
Popcorn
Muffins
Fruits
Frozen fruit bars
Crackers
Bagels
Baked potatoes
Nuts and seeds
It is vitally important that you do not substitute snacks for regular meals. Remember, snacks are small meals to be
eaten in addition to your regular meals and can be used strategically to help your performance.
Dietary Guidelines
ANJON Systems, Inc., South Bend, Indiana
1.
Choose daily servings from the five major food groups
2.
Eat three meals per day. When weight gain is desired, there should be an addition of two to three snacks.
3.
Cut down on the foods that are high in fat:
Red meats (steak, hamburger, franks, luncheon meats)
Pork products
Whole milk, ice cream, cream and cream sauce
Cheese and cheese sauce
Butter and margarine
Mayonnaise and Miracle Whip
Oils of all kinds (for cooking or salads)
Salad dressings
French fries or other fried potatoes such as chips
4.
Suggestions to lower fat intake
Buy lean cuts of meat and trim all excess fat
Keep meats to a moderate serving, substituting fish and poultry
Don't fry foods; bake, broil, boil, poach, steam or barbecue
Use all fats sparingly
Use dairy products made with whole milk sparingly
Avoid the use of products packed in oil
Substitute low calorie foods that will help lower your fat intake
5.
Increase intake of complex carbohydrates and grain products
Breads, rolls
Cereals
Pancakes, waffles
French toast
Pasta, rice
Vegetables
Fruit and fruit juices
6.
Refined sugars should not replace balanced meals
Foods that are high in refined sugar have a lower vitamin and mineral content
Many sweets are also high in fat (chocolate candies, pies, cakes)
7.
Water intake should be six to eight glasses a day
Stock Up On Good Nutrition
Cupboard
Refrigerator
Freezer
Spaghetti
Rice
Ramen noodles
Potatoes
Wheat crackers
Ry-Krisp
Spaghetti sauce
Minced clams
Tuna
Canned salmon
Kidney beans
Peanut butter
Bran flakes
Oat bran
Muesli
Raisins
"Lite" cheese
Parmesan cheese
Low-fat cottage cheese
Low-fat yogurt
Eggs
Bananas
Carrots
V-8 juice
English muffin
Pita bread
Multigrain bread
Orange juice concentrate
Broccoli
Spinach
Winter squash
Cut up chicken
Extra lean hamburger
Ground turkey
How Many Calories?
The body requires a certain amount of energy to maintain its basic functions (circulation of blood, breathing, etc.).
This is known as basal metabolism. Additional calories are necessary for the body to perform physical activities such
as walking, jumping, even writing notes in class. The procedure outlined below will estimate how much energy
(calories) the body needs to maintain current weight.
Each day, about 10 calories per pound of body weight are needed for basal metabolism. The amount of energy needed
for physical activities depends on how active an individual is. Below are three general classifications of physical
activity and the percentage of basal metabolism required for each physical activity level.
Activity Level
Sedentary:
Physical activity limited to walking and sitting
Percentage Above Basal
30%
Moderately Active:
Engaged in physical activities
involving standing and walking
50%
Very Active:
Regular or daily participation in
sports or other vigorous physical
activities
70% - 80%
To estimate total daily caloric needs, add estimated physical activity calories to estimated basal calorie needs.
For example: A 150-pound very active adult requires:
Basal calories
150 x 10 = 1,500
Activity calories
.70 x 1500 = 1,050
Total calories to maintain current weight
1,500 + 1,050 = 2,550
If you are looking to gain weight the healthy way, consume an additional 500 - 1000 calories per day above that
required to maintain your weight.
For example: A 235-pound very active athlete requires:
Basal calories
235 x 10 = 2, 350
Activity calories
.70 x 2350 = 1,645
Total calories to maintain current weight
2,350 + 1,645 = 3,995
Consuming approximately 4,500 - 5,000 calories per day will help this athlete increase weight at a rate of about one
pound per week.
WHAT IS THE BEST WAY TO GAIN BODY WEIGHT?
Eating habits must change to meet the dietary guidelines. There must be a sound nutritional base. Once this is
accomplished, the addition of liquid supplements such as Ensure Plus can be used to elevate calories to the desired
level. This is the correct way to gain muscle tissue and not fat.
HOW DO I REDUCE BODY WEIGHT?
Again, fallow the dietary guidelines to balance the diet. To estimate your daily caloric requirements, refer to the chart
below:
ESTIMATED DAILY CALORIC INTAKE IN RELATION TO CURRENT BODY WEIGHT
(During Hard Physical Workouts)
NOTE: Percentages of macronutrients should be 55-60% complex carbohydrates, 20-25% fat, and 15-20% protein.
(Refer to Dietary Guidelines).
WEIGHT LBS.
120
130
140
150
160
170
180
190
200
210
220
230
240
250
260
270
280
290
300
REDUCE
1,530
1,720
1,990
2,100
2,290
2 480
2 670
2 860
3,050
3,240
3,430
3,620
3,810
4,000
4,190
4,380
4,570
4,760
4,950
MAINTAIN
2,280
2,470
2,660
2,850
3,040
3,230
3,420
3,610
3,800
3,990
4,180
4,370
4,560
4,750
4,940
5,130
5,320
5,510
5,700
INCREASE
3,030
3,220
3,410
3,600
3,790
3,980
4,170
4,360
4,550
4,740
4,930
5,120
5,310
5,500
5,690
5,880
6,070
6,260
6,450