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Transcript
Nutritional Considerations
Nutrition

 Diet influences virtually every aspect of sports
participation.
 Performance
 Recovery from training and competition
 And to some extent, likelihood of injury
Knowledge of Nutrition

 Coaches and athletes may be familiar with the food
groups but often lack adequate nutrition information
and incorporate unfounded nutritional practices into
training programs.
 Athletes may be receiving nutritional education from
other sources.
 Parents, TV commercials, magazines
 Certified athletic trainers and strength &
conditioning coaches are most knowledgeable about
nutrition.
Eating for Sport Performance
 Academy of Nutrition and Dietetics indicates that
eating properly will:

 help you train longer and at a higher intensity
 delay the onset of fatigue
 promote recovery
 help your body adapt to workouts
 improve body composition and strength
 enhance concentration
 help maintain healthy immune function
 reduce the chance of injury
 reduce the risk of heat cramps and stomach aches.
Overview of Nutrients

Macronutrients
 Carbohydrates
 Fats (Lipids)
 Protein
Micronutrients
 Vitamins
 Minerals
Water
Caloric Intake (Rest + Activity)

 Caloric intake should be based the body weight goal.
 Total caloric intake should be determined by
calculating the basal metabolic rate (BMR) and the
energy needs for activity.
 The metabolic qualities of the activity should be
considered when calculating the need for each
energy-producing nutrient (carbohydrates, fats,
proteins).
Calculating Goal Weight

 Based on ideal body fat percentages
 10-22% Males
 20-32% Females
 To calculate goal weight:
 Current % body fat – Desired % body fat =
Nonessential body fat %
 Current body weight X Nonessential body fat %
(decimal form) = Nonessential fat (lbs)
 Current body weight – Nonessential fat (lbs) =
Ideal body weight (lbs)
Basal Metabolic Rate (BMR)

 The amount of energy needed to sustain functioning at rest.
 Female BMR = 655.1 + (9.6 X weight [kg]) + (1.9 X height
[cm]) – (4.7 X age [yrs])
 Male BMR = 66.5 + (13.8 X weight [kg]) + (5 X height [cm])
– (6.8 X age [yrs])
 Add daily activity to find amount of energy expended daily
 Sedentary - 20-40% of BMR
 Light Activity - 55-65%
 Moderate Activity – 70-75%
 Heavy Activity – 80-100%
 Sport participation > 200%
Carbohydrates

 Carbohydrates (CHO) provide energy for high-intensity
exercise
 Experts recommend 60% to 70% of daily calories be
supplied by CHO.
 Each gram of CHO provides 4 kilocalories.
 Average person stores approximately 1500 to 2000 kcals of
CHO, the majority of which is in the form of muscle and
liver glycogen. Small portion available as blood glucose.
 CHO are now classified on how fast they are oxidized.
Known as the Glycemic Index.
Carbohydrates

 CHO derived from plant sources, primarily grains, seeds, fruits, and
vegetables.
 Simple CHO – monosaccharides
 Sugars such as fructose, glucose, galactose
 Typically stimulate insulin release and blood glucose
fluctuations.
 Foods containing are high caloric and often referred to as empty
calories.
 Complex CHO – polysaccharides
 Whole-grain cereals & breads, vegetables, and fruits.
 Dietary fiber (indigestible CHO) essential for digestion.
Carbohydrates

 Simple and complex CHO are suitable to describe foods,
but these do not represent the way they are hydrolyzed
and absorbed by the body. (Table 6.1)
 Low Glycemic Index CHO
 Cause a steadier rise and decline in blood glucose and insulin.
Best for weight management and overall diet.
 High Glycemic Index CHO
 Typically result in a large and rapid rise in blood glucose and
insulin, followed by a rapid decrease in blood glucose. Best for
refueling after event.
Carbohydrate Loading

 Carbohydrate loading can benefit athletes involved in
aerobic sports, especially activities lasting 60 minutes or
more.
 Properly executed regimen of CHO loading can boost the
level of stored glycogen.
 1 week prior to the competition and includes a gradual
tapering of physical activity accompanied with a slight
increase in CHO ingestion.
Fats (Lipids)

 Fats are needed for energy, insulation, and protection of
organs.
 Fatty acids and glycerol make up fats.
 Fatty acids: Saturated and Unsaturated
 Experts recommend that fats compose 30% or less of
total calories. 10% saturated
 Each gram of fat supplies 9 kilocalories.
Fats

 Saturated - all of the available bonding sites on the fatty
acid molecule are occupied by a hydrogen atom. Derived
from animal sources (i.e., beef, pork, poultry, and dairy
products). Generally solid at room temperature.
 Unsaturated fats are structured in such a way as to prevent
all of the available bonding sites from being occupied by a
hydrogen atom. Plant based. Generally liquid at room
temperature.
Proteins

 Proteins are needed for tissue construction, enzyme
reactions, and energy during prolonged exercise.
 Experts recommend that proteins compose 10-15%.
 Each gram of protein supplies 4 kilocalories.
 Proteins are composed of amino acids
 20 different amino acids are used to make thousands of
proteins.
 8 are essential amino acids, which cannot be synthesized
by the body and must be ingested in the diet.
Proteins

 Sources include eggs, meats, dairy products, legumes, or
grains.
 Athletes who are on vegetarian diets must take care to eat
foods in the correct combination to provide all of the
essential amino acids.
 A solution to the problem is for such athletes to include
either eggs (ovolactovegetarian), milk products
(lactovegetarian), or both to ensure adequate supplies of
essential amino acids.
Protein Supplementation

 Protein supplementation is not recommended because:
 Increase saturated fat in the diet
 Overstress the liver and kidneys.
 NO scientific evidence that protein supplements enhance
muscles.
 During intense training, 1.2-1.8 grams protein/kg body
weight are recommended.
 0.83-1.2 g/kg for sedentary or light exerciser
 Normal diet provides adequate protein consumption for
intense training.
Vitamins

 Vitamins have various functions
 Regulate biochemical reactions (energy metabolism and cell and
tissue generation)
 Serving as antioxidants that protect cell structure.
 Vitamins contain no caloric value and a balanced diet supplies
the Recommended Daily Allowance (RDA).
 There are water- and fat-soluble types of vitamins.
 Water soluble: Vitamins C, B1, B2, B6, B12, niacin, folic acid, biotin,
and pantothenic acid.
 Fat soluble: vitamins A, D, E, and K.
Minerals

 Minerals are elements needed for various body functions.
 Provide structure, help maintain normal heart rhythm, assist
muscle contractility, promote neural conductivity, and regulate
metabolism.
 There is no scientific evidence to support taking minerals in
excess of RDA for performance.
 But endurance athletes may be at an increased risk of iron or
calcium deficiency
 Iron and Calcium RDAs
 Iron:10 mg for males and 18-20 mg for females
 Calcium: 1500 mg
Vitamins and Minerals

Athletes who do not eat a balanced diet should
be advised to include a vitamin and mineral
supplement.
A convenient method of supplementation
is a daily multivitamin
Megadoses of vitamins/minerals should
be avoided and could result in severe
consequences
Water (H2O)

 Water is necessary for human performance, as well as
survival.
 Adult water requirement at rest is approx. 2.5 liters daily,
but it can increase to 5–10 liters during heavy exercise,
especially in high temperature and humidity.
 Water lost during exercise needs to be replaced to maintain
body’s fluid balance.
 A reduction of body weight of 2-5% can impair function.
 Current recommendations are for every 1 lb lost due to
sweating, 20-24 oz. of water be consumed.
Nutritional Knowledge: The
Research

 Athletes are largely uneducated regarding proper nutrition,
even though they understand the importance of adhering to a
quality diet. (Torres-McGehee et al., 2012)
 Sources information come from family members (32%), fellow
athletes (32%), athletic trainers (30%), dietitians (30%), coaches
(28%), and TV, radio, or the Internet (10%) to obtain their
information. (Froiland et al., 2004)
 Hilton (2005) reported that 70% of university athletes (n = 345)
are falling short of their daily caloric needs.
Female Athletes

 As more women become involved in organized sports,
concerns have been raised regarding their special nutritional
considerations.
 Especially those involved in aesthetic sports that place an
emphasis on being lean, such as gymnastics, diving, and
dancing.
 Greenleaf and colleagues (2009) determined that 54% of college
athletes were dissatisfied with their current weight.
 Clinical disordered eating: 47% in lean sports; 20% in “nonlean” sports
Endurance Sports

Athletic energy deficit - athletes not consuming enough
calories to match their output. A new concern emerging in
athletics.
 Athletes with athletic energy deficit will be unable to support
vital body functions including bone growth.
 With insufficient energy post exercise repair is inhibited,
hormones affected, amenorrhea and slower/poor bone growth.
 Other adverse health-related consequences include:
depression, lethargy, attention deficits, sleep disorders, and
increases in body fat.
Wrestling

 Wrestling is one of only a few sports that match
participants on the basis of weight.
 Wrestlers often follow unhealthy weight loss procedures
to compete in lighter weight categories.
 Rapid weight loss occurs via dehydration.
 Dehydration occurs through the use of laxatives and diuretics,
fluid restriction, artificially induced sweating, and starvation.
 No definitive proof that such tactics actually present an
advantage.
Wrestling

 Short-term effects of repeated bouts of extreme weight
loss include: (Nelson, 1989; Williams, 1992)




Increased blood viscosity
Blood clots
Kidney, liver and pancreas problems
Ulcers
 Speculative long-term effects may include interference
with normal growth and development.
Wrestling Minimum Weight
Project (WMWP)

 Wisconsin instituted WMWP in 1989. (Oppliger et al., 1995)
 Weight loss must be no more than 3 lbs. of weight
loss/week.
 A minimum 7% body fat level was established.
 Testing of athletes along with nutrition education for
coaches was implemented.
 Feedback has been positive from 95% of coaches.
 Participation has increased.
Wrestling Rules

 The NFSH has developed a national wrestling rule #1-3-1
that states:
 “An ideal program would be one where a medical
professional would assist in establishing a minimum weight
through the use of checking body fat and hydration. The
recommended minimum body fat should not be lower than
7%” (NFHS, 2011)
 Weight cutting can have physiological effects on
performance. (ACSM; Oppliger et al., 1996, updated in 2010)
ACSM Recommendations for
Wrestling

 Education should be provided to coaches and wrestlers.
 Rubber suits, steam rooms, hot boxes, saunas, laxatives, and
diuretics should not be used for making weight.
 Weigh-ins immediately prior to competition.
 Daily weigh-ins need to be scheduled before and after practice.
 The body composition assessed prior to the season.
 Caloric intake needs to support the normal developmental
needs.
Conclusions
(ACSM, 2009; McArdle et al., 2009)

 Athletes do not consume the proper proportions of nutrients
 CHO amount depends on the athletes daily expenditure, sport,
gender, and conditions
 Protein needs can be met through diet alone
 Athletes eat too much “junk food”
 Athletes in sports that require lean bodies tend to eat diets with
insufficient calories
 Most athletes’ diets are deficient in important minerals, i.e., calcium,
iron, & zinc.
What Can the Coach Do?

 Coaches are an important source of nutrition information.
 People planning to enter the coaching profession should take at
least one basic college nutrition course.
 Attend in-service meetings, professional conferences, or
community education programs in sports nutrition.
 Subscribe to professional journals that include nutrition articles.
What Can the Coach Do?

 Locate nutrition experts, including dietitians, university
nutrition faculty, or sports medicine staff.
 Implement peer-led programs like Athletes Targeting Healthy
Exercise & Nutrition Alternatives (ATHENA). (Eliot et al., 2008)
 Have athletes keep a record of their diet that is reviewed
periodically by a person knowledgeable in nutrition.
 When working with children, discuss nutritional needs of the
athlete with parents.
General Dietary Guidelines for
Athletes

 Tailored to meet individual needs
 Nutrition should prepare athletes for: practice,
competition and recovery
 Educated to make proper food selection and informed
supplement using interactive resources
Sports, Cardiovascular, and
Wellness Nutrition practice
group (http://www.scandpg.org)
Precompetition Diets

 Foods eaten just before a contest will contribute virtually
nothing to performance.
 Experts recommend that the typical pregame meal should
be eaten no later than 1 to 4 hours prior to the contest.
(ACSM, 2009)
 Eat low-fat, easy-to-digest foods.
 Liquid meals increase hydration and are less likely to cause
bloating or “heavy” feeling.
 Foods should provide 150 to 300 grams of CHO or 3 to 5
grams/kg of body weight. (McArdle et al., 2009)
Nutrition During Competition

 One hour of highly intense exercise can reduce liver
glycogen by 55% and 2 hours can almost completely
deplete both liver and muscle glycogen.
 CHO consumption during long-duration exercise (1 to
3 hours at 70% to 80% VO2max ) allows muscle cells to
rely on blood glucose for energy.
 Recommended fluid source of CHO is 8 oz. of a 5%
CHO solution consumed every 15-20 min. Especially
for morning workouts.
Nutrition After Competition

 Dietary goals are to replace muscle glycogen and ensure
quick recovery.
 A carbohydrate intake of approximately 1.0–1.5 g/kg body
mass (0.5–0.7 g/lb) during the first 30 min and again every
2 h for 4–6 h will be adequate to replace glycogen stores.
 Timing of CHO ingestion is important as glycogen levels
will replenish faster if the food is consumed within 30
minutes – 1 hour.
 Protein consumed after exercise will provide amino acids
for building and repair of muscle tissue.
Nutrition and Injury Recovery

 Weight gain is a concern with forced inactivity due to injury.
 Athletes who are ill/injured should not reduce total caloric
intake as metabolism may increase as the body repairs itself.
 Recommend cross training during recovery.
 Runners can ride stationary bikes or run in swimming pools.
 Those with infectious illnesses and unable to exercise should
establish a caloric intake based on their BMR until they are
healthy.
Nutrition and Recovery

 CHO stimulates insulin/insulin growth factor which helps
tissue building.
 Proteins (amino acids) contain the building blocks for
connective tissue and muscle.
 Anti-inflammatory foods encouraged: garlic, cocoa, tea,
blueberries, pineapple
 Proteolytic enzymes are known to inactivate bradykinins,
reduce viscosity of extracellular fluid(swelling), and help
molecular debridement: cheese, rye, papaya
 Free fatty acids contain eicosanoids, which can reduce pain,
cause vasodilation and enhance the immune system: omega 3 &
omega 6 fatty acids
Managing Body Weight

 Body weight consists of water, fat, and lean tissue.
 Muscle is denser than fat.
 In order to maintain weight an athlete’s caloric intake must
equal caloric expenditure.
 Consume too many calories per day the excess calories are
converted to fat. Too few, stored fat will be metabolized to
form energy.
 Severe caloric restrictions (fasting) result in protein breakdown.
 Athletes should only weigh themselves once/week at the same
time of day and after going to the bathroom.
Managing Body Weight

 Percentage of body fat = the ratio of fat to lean body weight
 Better measurement for weight management and is
commonly referred to as body composition.
 Ranges for most active young females are 14-24% and
active young males are 7-17%.
 Lowest reference body fat for males is 5% and in females it is
12% (Sammarone Turocy et al., 2011)
 NATA position statement “Safe weight loss and
maintenance practices in sport and exercise” (Sammarone
Turocy et al., 2011) is an excellent resource
Minimal Competitive Weight (MCW)
% body fat can be used to accurately calculate an
athlete’s minimal competitive weight so they can
excel during the season.

Sample Equation: [MCW = LBW / % fat desired]
• Determine % fat desired (5%); (1 - % fat
desired = 0.95)
• A 135 lb athlete with 14% body fat = 135 x
0.14 = 18.9 lb fat
• 135 lb – 18.9 (fat weight) = 116.10 lb (LBW)
• MCW = 116.10 / 0.95 = 122 lbs
Supplements and Ergogenic
Aids

 Supplements have become very popular with athletes of
all calibers.
 Ergogenic Aid: Food/drink that has potential to increase
work output of the person using them
 Marketed to make athletes think they will improve their
personal performance and reach their goals faster.
 It is important for the consumer to evaluate the marketing
claims, research studies, and safety issues associated with
ergogenic aids. (Manore, Meyer, and Thompson, 2009)
 Many pose adverse health risks or are illegal and their use
will result in disqualification or other penalties.
Nutritional Supplements

 NATA released two comprehensive position stands
evaluating dietary supplements (Buell et al., 2013)
and anabolic-androgenic steroids (Kersey et al., 2012)
 Food first philosophy
 Dietary Supplement Health and Education Act
(DSHEA) of 1994
 Supplements can be divided into two categories:
Legal and Illegal
Nutritional Supplements
Write how it can increase performance, its adverse
effects, how it is regulated (banned, illegal, legal, dosage,
etc.) and how to get it.

 Caffeine
 Ephedra
 Androstenedione (andro)
 Dehydroepiandrosterone
(DHEA)
 Creatine
 Amino acids
 Nitric Oxide
 Herbals
 Anabolic Steroids
 EPO
 Amphetamines
 Gamma-Hydroxybutyrate
(GHB)
Anabolic-Androgenic Products
 Illegal supplements include the following but are mostly
legal products when used in therapeutic doses under
physician or veterinarian's care.

 Anabolic steroids – high doses build muscle but have many
adverse effects
 Erythropoietin (EPO) - stimulates RBC proliferation,
increased viscosity makes the heart work harder
 Amphetamines – stimulants that block fatigue messages to
the brain, associated cardiac problems
 Gammahydroxybutyrate (GHB) – deep sleep aid, suggested
HGH is released in this sleep cycle