Nutrition and Performance for Wrestling

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Transcript Nutrition and Performance for Wrestling

Nutrition and Performance
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Questions about sports nutrition
• Can diet improve athletic
endeavor?
• What is the optimal diet for
athletes?
• Does exercise increase the need
for vitamin and mineral
supplements?
• Do athletes (relying on strength
and power) need protein
supplements to maximize size
and power?
• What ergogenic aids are safe
andExercise
beneficial?
Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Principles of
Sports Nutrition
• A healthy, balanced diet is the
cornerstone
• Increase total energy intake to
adjust for calories burned during
exercise
• Keep dietary carbohydrate intake
high (55-70%)
• Drink large amounts of fluid
• Vitamin & mineral supplements
are not needed
• Ergogenic aids are unethical
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
2005---USDA Dietary Guidelines
• WEIGHT MANAGEMENT;
PHYSICAL ACTIVITY
Key Recommendations (Coaches)
• To maintain body weight in a healthy
range, balance calories from foods
and beverages with calories
expended.
• To prevent gradual weight gain over
time, make small decreases in food
and beverage calories and increase
physical activity.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
2005 Guidelines (Coaches):
WEIGHT MANAGEMENT; PHYSICAL ACTIVITY (cont)
• Engage in regular physical activity and reduce sedentary activities to
promote health, psychological well-being, and a healthy body weight.
– To reduce the risk of chronic disease in adulthood: Engage in at
least 30
minutes of moderate-intensity physical activity, above usual activity, at work
or home on most days of the week.
– For most people, greater health benefits can be obtained by engaging in
physical activity of more vigorous intensity or longer duration.
– To help manage body weight and prevent gradual, unhealthy body weight
gain in adulthood: Engage in approximately 60 minutes of
moderate- to vigorous-intensity activity on most days of the week while not
exceeding caloric intake requirements.
– To sustain weight loss in adulthood: Participate in at
least 60 to 90
minutes of daily moderate-intensity physical activity while not exceeding
caloric intake requirements. Some people may need to consult with a healthcare
provider before participating in this level of activity.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
2005 Guidelines:
FOOD GROUPS TO ENCOURAGE
• Consume a variety of fruits and vegetables (2
cups fruit, 2 ½ cups vegetables per day for a
2,000-calorie intake (higher or lower
depending on the calorie level).
• In particular, select from all 5 vegetable
subgroups (dark green, orange, legumes,
starchy vegetables, and other vegetables)
several times a week.
• Consume 3 or more ounce-equivalents of
whole-grain products per day, with the rest of
the recommended grains coming from
enriched or whole-grain products (at least
half the grains should come from whole
grains).
• Consume 3 cups per day of fat-free or lowfat milk or equivalent milk products.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Physical activity
oils
fruits
milk
vegetables
Grains
Visit www.mypyramid.gov for details (and to
choose your food intake plan).
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
meat
and
beans
2005 Guidelines:
CARBOHYDRATES
• Choose fiber-rich fruits, vegetables, and
whole grains often.
• Choose and prepare foods and beverages
with little added sugars or caloric
sweeteners, such as amounts suggested by
the USDA MyPyramid and the DASH
Eating Plan.
• Reduce the incidence of dental caries by
practicing good oral hygiene and
consuming sugar- and starch-containing
foods and beverages less frequently.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
2005 Guidelines: FATS
• Consume less than 10% calories from saturated fatty acids
and less than 300 mg/day of cholesterol, and keep trans
fatty acid consumption as low as possible.
• Keep total fat intake between 20 to 35% of calories, with
most fats coming from sources of polyunsaturated and
monounsaturated fatty acids, such as fish, nuts, and
vegetable oils.
• When selecting and preparing meat, poultry, dry beans, and
milk or milk products, make choices that are lean, low-fat,
or fat-free.
• Limit intake of fats and oils high in saturated and/or trans
fatty acids, and choose products low in such fats and oils.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
2005 Guidelines:
SODIUM AND POTASSIUM
• Consume less than 2,300 mg
(approximately 1 tsp of salt) of
sodium per day.
• Choose and prepare foods with
little salt. At the same time,
consume potassium-rich
foods, such as fruits and
vegetables.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
2005 Guidelines: ALCOHOLIC
BEVERAGES
• Those who choose to drink alcoholic beverages should do so
sensibly and in moderation—defined as the consumption of up
to one drink per day for women and up to two drinks per day for
men.
• Alcoholic beverages should not be consumed by some
individuals, including those who cannot restrict their alcohol
intake, women of childbearing age who may become pregnant,
pregnant and lactating women, children and adolescents,
individuals taking medications that can interact with alcohol, and
those with specific medical conditions.
• Alcoholic beverages should be avoided by individuals engaging
in activities that require attention, skill, or coordination, such as
driving or operating machinery.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
The Most Important Sports Nutrition
Principle for Athletes: Increase intake of
carbohydrate (55-70%)
• Muscle and liver glycogen (stored
carbohydrate) found to play important
role in intense exercise.
• Exhaustion is tied to low muscle
glycogen levels and is limiting in bouts
lasting longer than 60-90 minutes.
• When muscle and liver glycogen is
low, a high work output cannot be
maintained.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Second Most Important Sports Nutrition
Principle: Increase Fluid Intake
• As the muscle burns fuel, 70-80% is
transformed into heat (body heat can rise
1°C/5 min, causing death in 20-30 min).
• During exercise, sweat evaporation
accounts for >80% of heat loss (1 liter of
sweat evaporation on the skin removes
600 kcal heat).
• Sweat losses can range from 0.5-3.7 l/hr
(avg. 32oz/hr) of exercise, depending on
the work rate and environmental
conditions.
• Loss of >2% body water impairs
performance (e.g., 3 lbs in a 150 pound
athlete).
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
ACSM Position Stand on
Exercise & Fluid Replacement
• Emphasize fluid intake before exercise by drinking adequate
fluids during the day before the event, and drink about 500
ml (about 16 oz) two hours before exercise.
– Urine should be light-colored, good volume, no strong smell.
• Athletes should start drinking early and at regular intervals
during exercise to replace nearly all the water lost from
sweating.
– 0.5-2 cups fluid/ 10-15 min of exercise
– 2 cups / pound of weight loss
– Gastric emptying is promoted by >600 ml gastric volume
(maintain largest fluid volume in stomach that is tolerable)
It’s better to gulp 16oz as opposed to sipping fluids
– Fluids should be sweetened (6-8% carb), flavored, and cooled to
stimulate intake (Gatorade is 6% and Powerade is 8%)
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
ACSM Position Stand on Exercise & Fluid Replacement (cont.)
• If the event is longer than 1 hour,
carbohydrates and electrolytes should be
included in fluids ingested.
• Carbohydrates should be ingested at a rate
of 30-60 g/hr (0.6-1.2 liters or 16-32 oz)
of most sports drinks with 4-8% carb)
• Inclusion of sodium (0.5-0.7 g/l water)
enhances palatability, promotes fluid
retention (less urination), and helps
prevent hyponatremia in certain athletes
who drink excessive plain water during
ultra events
– 1 liter sweat has 0.4-1 g sodium
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Vitamin and Mineral Supplements Are
Not Needed
In a joint statement, the American College of
Sports Medicine, American Dietetic Association,
and Dietitians of Canada have stated,
“In general, no vitamin and mineral supplements should be required
if an athlete is consuming adequate energy from a variety of foods to
maintain body weight. If an athlete is dieting, eliminating foods or
food groups, is sick or recovering from injury, or has a specific
micronutrient deficiency, a multivitamin/mineral supplement may be
appropriate. No single nutrient supplements should be used without
a specific medical or nutritional reason (e.g., iron supplements to
reverseExercise
iron Testing
deficiency
anemia).”
and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
ADA Summary on Protein Intake
• “Recommended protein intakes can generally be met
through diet alone, without the use of protein or amino
acid supplements, if energy intake is adequate to maintain
body weight...Athletes should be aware that increasing
protein intake beyond the recommended level is unlikely
to result in additional increase in lean tissue because there
is a limit to the rate at which protein tissue can be
accrued...Although the protein quality of a vegetarian diet
is adequate for adults, plant proteins are not as well
digested as animal proteins. Thus, to adjust for
incomplete digestion, an increase of about 10% in the
amount consumed may be made.”
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Use of ergogenic aids usually
have little or no value and in
some cases are illegal
• Ergogenic = substances or methods that
tend to increase performance capacity
– Nutritional aids (carbohydrates, vitamins,
proteins)
– Pharmacological aids (steroids,
amphetamines)
– Physiological aids (oxygen, blood doping)
– Mechanical aids (biomechanical aids)
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Nutritional Ergogenic Aids
• Prohormones: compounds such as androstenedione,
androstenediol, and dehydroepiandrosterone that are
purported to increase testosterone, improve recovery, and
build muscle mass.
• Creatine preparations: supplements that contain creatine
monohydrate, and are advertised to improve power
performance and build muscle mass.
• Proteins and amino acids: claimed effects include
increases in muscle mass, strength, and endurance.
• Natural and herbal products: ginseng, Echinacea, saw
palmetto, tribulus, and kava kava which are claimed to
improve energy, strength, endurance, and immune
function.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Nutritional Ergogenic Aids (cont.)
• Diuretics: herbal diuretics and stinging nettle which
purportedly prevent water retention, swelling, gout, and
high blood pressure.
• Energy enhancers, vitamins, and antioxidants: vanadyl
sulfate, taurine, and vitamins which are postulated to
improve recovery, aid in rehydration and glycogen
replenishment, and provide added energy.
• Mental enhancers: plant extracts, amino acids, alkaloids
(ephedrines and caffeine), minerals, and vitamins that are
alleged to modulate mood, boost metabolism, increase
adrenaline output, and provide energy and power.
• Fat burners: L-carnitine, inositol, and choline that are
asserted to increase lean muscle mass and burn fat.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
ADA/ACSM Guidelines
• The 1994 Dietary Supplement Health and Education Act
allows supplement manufacturers to make claims regarding the
effect of products on the structure/function of the body, as long as
they do not claim to diagnose, mitigate, treat, cure, or prevent a
specific disease. Performance can be categorized as follows:
– Those that perform as claimed.
– Those that may perform as claimed but for which there is
insufficient evidence of efficacy at this time.
– Those that do not perform as claimed.
– Those which are dangerous, banned, or illegal, and
consequently should not be used.
• Athletes should be counseled regarding the use of ergogenic aids,
which should be used with caution and only after careful
evaluation of the product for safety, efficacy, potency, and legality.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Ergogenic Aids That Work??
• Steroids and Steroid-Like Compounds
– Fact: Claims are true for most people who also engage in intensive
resistance exercise. Side effects are legion.
– Prohormones are a class of androgenic steroids that either convert to
testosterone directly or mimic testosterone by forming androgen-like
derivatives (e.g., nandrolone). These compounds include
dehydroepiandrosterone (DHEA), androstenedione, 5-androstenediol,
and 4-androstenediol, all now sold as prohormones in the U.S.
marketplace. Most studies indicate that some androgen supplements
convert to testosterone, but also estrogen subfractions. The net effect
is no increase in protein synthesis, muscle mass, or strength.
– Claim: Increase muscle mass & strength, decrease fat mass, increase
aggressiveness
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
• Doping with growth hormone:
– Reputation of being effective in
building skeletal mass, reducing fat
mass, and improving submaximal and
maximal aerobic endurance among
athletes.
– Crucial in energy metabolism and
body anabolism, and has multiple
benefits when administered to adults
with growth hormone deficiencies.
– Currently, the effects of growth
hormone in improving athletic
performance, muscle strength, and
recovery from intensive exercise are
unproven, but studies are ongoing.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©
Ergogenic Aids That Work??
• Creatine---ACSM consensus
statement
– Creatine supplementation can increase
muscle phosphocreatine content, but not in
all individuals.
– Exercise performance involving short
periods of extremely powerful activity can
be enhanced with creatine supplementation
(e.g., 5-7 d of 20 g/d), especially during
repeated bout of activity; does not increase
maximal isometric strength, the rate of
maximal force production, nor aerobic
exercise performance. Effects are relatively
small.
– Creatine supplementation leads to weight
gain within the first few days; due to water
retention.
Exercise Testing and Prescription: A Health-Related Approach by Nieman. McGraw-Hill, 2006.©