Chapter 5- Nutritional Considerations
A. Six Classes of Nutrients
- Carbohydrates (CHO) 55-70% of caloric intake
n Body’s most efficient energy source
n Sugars (Should account for <15% of caloric intake)
n Simple (sugars) and complex (starch and fiber)
n Monosaccharides
n single sugars (fruits, syrup and honey)/Glucose
n Disaccharides
n 2 sugars combined (milk sugar, table sugar)
n Starches-Complex CHO (Rice, potatoes, breads)
n Broken down into Sugar
n Fiber (Structural part of plants and is not digestible in humans) 25 grams/Day
n Soluble
n Gums, pectin
n Oatmeal, legumes, and some fruits
n Insoluble
n Cellulose
n Grain breads and bran cereal
- Protein (12-15% of daily caloric intake)
n Required for growth, maintenance, and repair of the body
n Aid with enzyme, hormone, and enzyme production
n Amino Acids
n Basic units that compose protein
n 20 amino acids compose the majority of body protein
n Most can be produced by the body while others (essential) must be consumed
n Animal products contain all essential amino acids
n Incomplete sources (i.e. plants sources) do not contain all essential amino acids
n Most diets are rich in protein and often athletes consume twice the amount that is recommended
n Excess protein is converted to fat and may result in dehydration and potential kidney damage
n Increased physical activity results in increased need for protein in the diet
n Protein Supplements
n Approximately 1-1.5g/kg body weight of protein should be consumed for increasing muscle mass
n Often times exceeded with normal diet and supplementation is not necessary
n
- Fat (Most concentrated source of energy)
n Saturated (fatty acids derived from animal products)
n Unsaturated (plant derivatives - liquid at room temperature)
n Cholesterol (consume <300mg/day)
n Omega-3 fatty acids (unsaturated fat) aids in reduction of heart disease, stroke, hypertension)
n Found in cold-water fish
n
- Vitamins (13) serve as regulators in many body processes
n Fat soluble
n Vitamins A, D, E , K
n Found in fatty portion of foods and oils
n Water soluble
n Vitamin C, B-complex vitamins (B6, B12,) Thiamin, Riboflavin, Niacin, Folate, Biotin, Pantohenic acid
n Help to regulate metabolism but cannot be stored
n Vitamin C
n to prevent common cold and slow aging
n May cause kidney stones and diarrhea
n Vitamin E
n Protects cell membranes from damage
n Little evidence to support enhancing performance or life expectancy
n B-complex vitamins
n Aid in release of energy from CHO, fat, and protein
n If additional energy is required, increased caloric intake is necessary
n
5. Minerals (20 minerals) have essential roles in the body
n Phosphorus
n the second most abundant mineral in the body
n 85% of it is found in the bones.
n It's main purpose is for building strong bones and teeth, but this mineral is used by practically every cell in the body.
n Copper
n essential mineral
n Usually found in foods containing iron.
n The liver and brain contain the largest amounts of copper in the human body
n Necessary for the growth, development, and maintenance of bone, connective tissue, brain, heart, and many other body organs.
n It is involved in the formation of red blood cells, the absorption and utilization of iron, and the synthesis and release of life-sustaining proteins and enzymes.
n Deficiency: hemoglobin production is decreased and copper deficiency anemia can result.
n Insufficient amounts can lead to inefficient utilization of iron and protein, diarrhea and stunted growth. Various enzyme reactions require copper.
n Zinc
n It fuels everything from manufacturing DNA, wound healing, maintaining a strong immune system, to fighting colds, flu's, and other infections.
n Zinc is critical for proper functioning of the male reproductive system; the human body does not produce zinc on its own, so it must be obtained from outside sources.
n The mineral zinc can be found in both animal and plant food sources, but the richest source of zinc comes from animal food sources.
n Iodine
n two thirds of the body's iodine is in the thyroid gland.
n It plays a major role in thyroid health (thus controlling metabolism),
n Commonly derived from the diet in the form of iodized table salt (one teaspoon of salt = 300 mcg of iodine).
n Sea salt is not iodized and is not a good source of iodine, and most salty snacks do not contain iodized salt either.
n Iodine deficiency is most common in people living in undeveloped countries
n Severe iodine deficiency often occurs in people that are afflicted with thyroid disease or a hyperthyroid disorder, or those who have developed a goiter.
n Symptoms of iodine deficiency may manifest as extreme fatigue, weight gain, facial puffiness, constipation, slowing of both physical and mental processes, and lethargy.
n Fluorine
n Trace Mineral not technically an essential mineral
n because the body can live without it
n significant role in keeping teeth and bones healthy and strong
n been added to toothpaste and some drinking water supplies
n Iron (energy metabolism and oxygen transport)
n Iron is a mineral essential for life.
n It is present in every living cell and is necessary for the production of hemoglobin (primary component of red blood cells), myoglobin (major protein of muscle cells), and certain enzymes.
n Iron, along with calcium, are the two major deficiencies of American women (one of the reasons due to menstruation and bleeding)
n Can cause weakness, inability to concentrate, the susceptibility to infection, impaired performance, and in general, ill health.
n Other people at risk of iron deficiency include dieters, vegetarians and athletes.
n Calcium and copper must be present for iron to function properly, and ascorbic acid (vitamin c) enhances absorption.
n Iron is necessary for proper metabolizing of B vitamins.
n Magnesium (energy supplying reactions)
n Magnesium plays an important role in at least 300 fundamental enzymatic reactions and for that reason is of vital importance in our health.
n Magnesium is found in dairy products, fish, meat and seafood, as well as in legumes, apples, apricots, avocados, bananas, whole grain cereals, nuts, dark green vegetables, and cocoa, while hard water and mineral water may also supply it in fair quantities
n Calcium (bone formation, clotting, muscle contractions)
n Young adult requires 1000mg/day
n Calcium is the most abundant mineral in the body.
n Primary function is to build and maintain skeletal tissue.
n Ninety-nine percent of the body's calcium supply resides in the bone and teeth.
n Osteoblasts are bone-forming cells in which calcium phosphate is deposited.
n Ameleoblasts are the tooth- forming cells that deposit calcium to form teeth
n Maintaining the stability of fibrin, which allows blood to clot
n Required for the transmission of nerve impulses.
n Controls the flow of fluid through cell membranes.
n Also has a vital role in muscle contraction and relaxation.
n Sodium and Potassium (nerve conduction)
n Sodium known as salt
n too much sodium
n increased risk of heart disease, stroke and high blood pressure, the development of kidney stones and other types of ailments
n the body needs more than 100 milligrams per day to function properly
n Sodium is an electrolyte
n With chloride and potassium, helps control the electrical charges that occur between cells.
n These electrical charges are used by cells to communicate with one another. The electrical charges are also what give our five senses the ability to see, smell, touch, hear and taste.
n Approximately 30% of the sodium mineral inside the body is stored in the bones and the balance is found in body fluids.
n Sodium is a main component of blood plasma and approximately 60% is contained in the fluids that surround cells.
n About 10% of the body's sodium is stored inside the cells. This division helps maintain a proper balance of water inside as well as outside these cells.
n Its presence in the circulatory system helps the body keep blood pressure and the overall volume of blood flow within normal ranges.
n Sodium helps keep the blood from clotting, which can be a very dangerous situation.
n In the blood, sodium together with potassium helps maintain the blood's delicate pH balance.
n Sodium also helps carry important nutrients to the cells.
n In the digestive system, sodium assists in the process of metabolizing foods into energy.
n It protects the stomach lining by preventing the acids inside the stomach from burning it
n Potassium is the third most abundant mineral in the body
n considered an electrolyte
n The human body has about a 4 1/2 ounce supply and most of it is located inside muscle cells.
n Studies have shown that potassium may help to prevent high blood pressure and may enhance the effect of antihypertensive medications.
n Both physical and mental stress can lead to a deficiency in potassium.
n Alcohol, coffee, and sugar deplete potassium levels in the body.
n Potassium assists in muscle contractions
n It is critical to maintaining a normal heartbeat or heart rhythm.
n Potassium also functions in the conduction of nerve impulses and enables the body to convert glucose into energy, which is then stored in reserve by the muscles and liver.
- Water Most essential nutrient
n most abundant in body (60% of body weight)
n Essential for all chemical processes
n Lack of water (dehydration) can lead to illness and death
n Body has mechanisms to maintain homeostatic levels of hydration (kidneys and solute accumulation
n A 6% carbohydrate solution appears to be optimal for Fluid Replacement
OTHER
v Requirements vs. Recommendations
Ø RDA (Recommended Daily Allowance) vs. DRI (Dietary Reference Intake)
v Food Labels
Ø Aids consumers in determining levels of nutrients in foods
v Creatine Supplementation
Ø Naturally occurring substance in body produced by kidneys, pancreas and liver
Ø Found in meat and fish
Ø Role in metabolism
Ø Two types (Free Creatine and Phosphocreatine)
§ Phosphocreatine is stored in skeletal muscle
§ Positive effects
· increase intensity of workouts
· lactic acid buffer
· stimulates protein synthesis
· decreases total cholesterol and total triglycerides and improves HDL-LDL ratio
· increases fat free mass
§ Negative effects
· weight gain
· muscle cramping
· gastrointestinal disturbances and renal dysfunction
Ø Not a banned substance, however, distribution by NCAA institutions is banned
v Caffeine
Ø Not detrimental to performance
§ Enhances fat utilization and endurance performance
§ Makes calcium more available allowing muscles to work more effectively
§ may cause slight headaches (Withdraw)
v Alcohol- 21 years of age!!!!
Ø Provides energy for the body & has little nutritional value
Ø Central nervous system depressant
§ decreases coordination, slows reaction time, decreases mental alertness
Ø increases urine production (diuretic effect)
v Organic, Natural, of Health Foods
Ø Claim to be safer and nutritionally superior due to absence of pesticides and fertilizers
Ø All foods are organic due to presence of carbon
Ø More expensive no increased benefit physiologically
Ø Processing (preservatives) helps to maintain nutritional value
v Herbs
Ø Safe to ingest as natural medicines we few side effects (occasional allergic reaction)
Ø Offer nutrients that nourish brain, glands and hormones
Ø Don’t need to consume with food - contain own digestive enzymes
Ø Work with the body’s functions (whole body balancers)
Ø Caution must be exercised as there is no governmental control or regulation
v Vegetarianism
Ø While practiced intelligently (not a fad) a vegetarian diet can result in deficiencies
Ø Diet must be carefully planned
Ø Total vegetarian (vegan)
§ all plant diet, no animal products
§ must be certain to consume enough calories and vit B12, calcium, zinc, and iron
Ø Lactovegetarian
§ Consume plant foods and milk products
§ Must watch iron and zinc levels
Ø Ovolactovegetarian
§ Consume plant foods, milk products and eggs
§ Iron is still a concern
Ø Semivegetarian
§ Still primarily plants but all other products are consumed except red meat.
v Pre-event meal
Ø Traditional steak and eggs
Ø Long term food consumption is more important than immediate consumption
Ø Purpose should be to provide competitor with nutrients/energy and fluids for competitions
§ taking digestibility into consideration
Ø Liquid Supplementation
§ Extremely effective and successful
§ 225-400 calories per serving
§ Successful in reducing pregame symptoms of dry mouth, abdominal & leg cramps, nervous defecation and nausea
Ø Food generally takes 4 hours to clear stomach and upper GI tract
§ Liquid supplements clear stomach and upper bowel before game time, settling the stomach and making available nutrients
Ø The pre-event meal should be
(1) Higher in carbohydrates
(2) Easily digested
(3) Eaten 2 to 4 hours before an event, and
(4) Acceptable to the athlete
§ Glycogen super compensation involves maximizing the stores of carbohydrate in muscle and liver before a competitive event.
§ Increase muscle and liver glycogen stores prior to major event by altering eating and training habits
§ Decrease training at least 48 hours prior to event
§ Increase CHO loading to increase glycogen stores and positively impact muscle glycogen and muscle endurance
Ø Six-day period (Glycogen Supercompensation)
§ Phase I (Days 1-2): hard training with reduced CHO intake
§ Phase II (Days 3-5): decrease training and increase CHO (potentially increasing glycogen stores 50-100%)
§ Phase III (Days 6-7): resume normal diet
· Glycogen SupercompensationNot clearly demonstrated as being beneficial in endurance activities
· Do not perform more than 2-3 times per year
· Ideally for prolonged duration events
Ø Body composition analysis
§ Body comp is the relationship between fat tissue and lean body tissue