Transcript Fats - bboadwine

Chapter 5: Nutritional
Considerations
© 2007 McGraw-Hill Higher Education. All rights reserved.
Nutrients
• Diet
– Foods regularly eaten; does not always mean losing weight
• Nutrition
– Science of food substances & what they do in the body
• Nutrients
– Specific food substances
• Nutrients have 3 roles
– Grow, maintain and repair all body cells
– Regulate body processes
– Supply energy for cells
© 2007 McGraw-Hill Higher Education. All rights reserved.
6 Classes of Nutrients
– Carbohydrates (CHO)
– Protein
– Fat
Macronutrients
– Vitamins
– Minerals
– Water
Micronutrients
© 2007 McGraw-Hill Higher Education. All rights reserved.
Carbohydrate (CHO)
• Most efficient energy source
• Makes up at least 55-60% of total caloric intake
• Simple
– Refined sugars with fewer essential nutrients
– honey, yogurt, fruit juice, candy, desserts
– Digested quickly
• Complex
– Have more nutrients and fiber & take longer to digest
– Whole grain bread, cereals, rice, vegetables
• Fiber
© 2007 McGraw-Hill Higher Education. All rights reserved.
Carbohydrate cont.
• Should eat more complex carbohydrates
than simple
• Simple carbohydrate intake should consist
primarily of fruits, yogurt or milk not candy
and desserts
• Foods high in refined sugar are typically
low in nutrients
© 2007 McGraw-Hill Higher Education. All rights reserved.
Fats
• Most concentrated source of energy
• Serves to make food flavorable and contain
fat soluble vitamins (A, E, D, K)
• Needed for hormores, hair and skin
development
• Fats should be less than 25% of caloric
intake
• High fat diets lead to obesity, certain
cancers and coronary heart disease.
© 2007 McGraw-Hill Higher Education. All rights reserved.
Proteins
• Required for growth, maintenance, and
repair of the body
• Helps repair/build muscles
• Aid with enzyme, hormone, and enzyme
production
• Provides little energy
• 12-15% of daily caloric intake
• Red meat, chicken, fish, eggs, beans, peanut
butter
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Amino Acids
–
–
–
–
Building blocks of protein
20 amino acids compose the majority of body protein
Body can make most of them
Essential Amino Acids – can’t be made by body, so
must be eaten
– Animal products contain essential amino acids
– Plant sources contain incomplete amino acids
© 2007 McGraw-Hill Higher Education. All rights reserved.
Vitamins
• Vitamins (13) serve as regulators in many
body processes
• Fat soluble
– Fat soluble vitamins A, D, E , K
– Will be stored in the body
– Found in fatty portion of foods and oils
• Water soluble
–
–
–
–
Vitamin C, B-complex vitamins
Help to regulate metabolism but cannot be stored
Each serves a series of roles
Excess are secreted in urine daily
© 2007 McGraw-Hill Higher Education. All rights reserved.
Vitamins
•
•
•
•
Vitamin D – becomes activated by sunlight
Vitamin K – helps with blood clotting
Vitamin C – helps improve immune system
Folic acid – important during pregnancy
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Anitoxidants
– May prevent premature aging, cancers, heart
disease and other health problems
– Include vitamins A, C, E
– Found in a number of dark green, deep yellow
and orange fruits and vegetables
• Vitamin Deficiencies
– Illness that results from a deficit in a particular
vitamin/mineral
– Are avoidable if an adequate diet is consumed
© 2007 McGraw-Hill Higher Education. All rights reserved.
Minerals
•
•
•
•
20 minerals have essential roles in the body
Many are stored in liver and bones
Help with strong bones and teeth
Calcium is most abundant mineral in body
–
–
–
–
Calcium/phosphorus – strong bones
Iron – oxygen transportation in blood
Magnesium – energy supplying reactions
Sodium and Potassium – nerve conduction
© 2007 McGraw-Hill Higher Education. All rights reserved.
Water
• Most essential nutrient
• Most abundant nutrient – 60% of body
• Essential for all processes & regulates body
temp
• Need 8 cups/day or
• Drink number of ounces that equals ½ your
body weight
– 100 pound person needs 50 oz/day
• Dehydration – lack of water can lead to
overheating, illness and death
© 2007 McGraw-Hill Higher Education. All rights reserved.
Electrolytes
•
•
•
•
•
Some minerals are electrolytes
Sodium, potassium, magnesium, and calcium
Sweating can lead to loss of electrolytes
Helps maintain hydration, decrease cramping
Drinking sports drinks – Gatorade or Powerade
will provide extra electrolytes during activity
© 2007 McGraw-Hill Higher Education. All rights reserved.
Nutrient Deficiency Diseases
• Osteoporosis
– Low calcium/phosphorus
– Bones are fragile and break easily
– More common in women
• Anemia
– Low iron
– Decreases ability of blood to carry oxygen
– Feel tired and weak especially with exercise
© 2007 McGraw-Hill Higher Education. All rights reserved.
© 2007 McGraw-Hill Higher Education. All rights reserved.
MyPlate
• Goal is to provide visual representation of
ideal diet.
• Half of your plate should be fruits and
vegetables.
• The other half of your plate should be
protein and grains, with grains being
slightly more than protein.
© 2007 McGraw-Hill Higher Education. All rights reserved.
• 5 Healthy Food Groups
–
–
–
–
–
Grains
Fruits
Vegetables
Milk
Meat and Beans
• Oils
© 2007 McGraw-Hill Higher Education. All rights reserved.
Nutrient Dense
Junk Food/Empty
Calories
High nutritional
value in relationship
to number of calories
Low nutritional value
in relationship to the
number of calories
High nutrients
Low calories
Low nutrients
High calories
© 2007 McGraw-Hill Higher Education. All rights reserved.
Production of Energy From
Foodstuffs
• Energy is produced with breakdown of CHO, fat or protein
• Short-term, high-intensity activity
– CHO
• Endurance activity
– CHO and fat
• Protein usually less than <5% of energy
© 2007 McGraw-Hill Higher Education. All rights reserved.
© 2007 McGraw-Hill Higher Education. All rights reserved.
Dietary Supplements: Myths
and Misconceptions
– Increase in activity does not mean more
vitamins are needed
– Supplements do not always help performance
– Placebo effect = phychological or mental boost
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Little research done on some supplementss
– FDA oversees supplements
– Has only banned ephedrine
• Before using supplements ask a MD or
nutritionist
• Coaches should not provide or handout any
supplements
– May break the law
© 2007 McGraw-Hill Higher Education. All rights reserved.
Vitamin Supplements
• If you eat a balanced diet you probably don’t
need a vitamin
• Taking more than the DRI level will not improve
performance
• Extra water soluble vitamins will be excreted
with urine
• Fat soluble vitamins (A, D, E, K) will be stored
in the body – can reach harmful levels
© 2007 McGraw-Hill Higher Education. All rights reserved.
Mineral Supplements
• Calcium and iron tend to be low
• Calcium – most abundant mineral in body
–
–
–
–
Needed for strong bones and maintenance
Young adult requires 1000mg/day
Females tend not to get enough calcium in diet
Exercise and weight bearing activities also increase
bone strength
– Milk is best source
• Lactose intolerant
– Don’t have enzyme lactase and can’t digest milk
– Causes upset stomach and gas
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Iron Supplements
– Iron deficiency is common in females
– Low iron = feel weak and tired
– Difficult for blood to carry oxygen
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Protein Supplements
– Most don’t need protein supplements
– Need about 1-1.5g per kg of body weight for
increasing muscle mass
– Usually have more than this is diet
• Creatine Supplements
–
–
–
–
Naturally made in kidneys, pancreas and liver
Found in meat and fish
Role in metabolism
Two types (free creatine and phosphocreatine)
© 2007 McGraw-Hill Higher Education. All rights reserved.
– 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 include weight gain, muscle
cramping and gastrointestinal disturbances and renal
dysfunction
– Not a banned substance, however, distribution by
NCAA institutions is banned
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Herbs
– Natural alternatives to drugs and medications
– Safe to ingest as natural medicines with few
side effects (occasional allergic reaction)
– Don’t need to eat with food
– Must be careful because there is no regulating
agency or governmental control
– Must tell your doctor if you take any herbs or
natural supplements
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Ephedrine
– Stimulant used in diet pills, illegal recreation
drugs and legitimate OTC medications
– Similar to amphetamine
– Banned by FDA in 2003
– Banned in athletics
– Known to cause
•
•
•
•
Heart attack, stroke, fast heart beat
Paranoid psychosis, depression, convulsions, coma
Fever, vomiting, palpitations, hypertension
Hypertension and respiratory depression
© 2007 McGraw-Hill Higher Education. All rights reserved.
Popular Eating and Drinking
Practices
• Caffeine Consumption
– Central nervous system stimulant
– carbonated beverages, coffee, tea, soda, chocolate
– Increase alertness and decrease fatigue
– Too much causes nervousness, irritability,
increased heart rate and headaches
– Addictive
– Withdrawal may cause headache (HA)
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Alcohol Consumption
– Provides energy for the body
• 7 calories per gram of alcohol
– Little nutritional value
– Central nervous system depressant
• decreases coordination, slows reaction time,
decreases mental alertness
• increases urine production (diuretic effect)
– Not recommended for use by athletes before,
during or after physical activity
© 2007 McGraw-Hill Higher Education. All rights reserved.
Vegetarianism
• Most of diet is from plant sources
• May not eat any animal products
– Meat, eggs, cheese
• Economic, philosophical, religious, cultural,
or health reasons
• Diet must be carefully planned, so there are no
deficiencies
© 2007 McGraw-Hill Higher Education. All rights reserved.
Pre-game Nutrition
• Should be eaten 4 hours before activity
– Gives time for food to leave stomach & upper GI
• Food eaten days before is more important than
pre-game meal
• Purpose to provide quick energy and blood
sugar
• Liquid meals/drinks are often a good option
– reduces dry mouth, abdominal & leg cramps,
nervous defecation and nausea
• Eat what the individual usually eats; don’t try
new foods
© 2007 McGraw-Hill Higher Education. All rights reserved.
Fast Foods
• America is the world of fast food junkies
• Often meal of choice during travel
• High Fat
– Usually 40-50% of the calories are from fat
• Portion sizes
• Read nutritional information
• Pick more healthy options
– Grilled chicken, no mayo, fruit, small french
fries
© 2007 McGraw-Hill Higher Education. All rights reserved.
Low Carbohydrate Diets
• Numerous versions
– Most replace CHO intake with protein and fat
• Unused CHO is quickly turned into fat
– CHO increases insulin production = insulin
encourages fat to be deposited & triggers a
hunger response
© 2007 McGraw-Hill Higher Education. All rights reserved.
Glycogen Supercompensation
• “Carb loading”
• Glycogen is stored energy
• Increase muscle and liver glycogen stores before
an endurance activity
• Glycogen is easily stored if you eat immediately
after exercise – the muscle is able to absorb or
hold more glycogen at that time
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Takes 6 days to Carb load
– 5&6 days before event : train hard and decrease
CHO intake
– 3&4 days before: decrease training at increase
CHO intake - 50-100%
– 1&2 days before: no activity and normal diet;
no glycogen will be used
• Benefits aren’t clearly known
• Do not try more than 2-3 times per year
• Ideal for extreme endurance events
© 2007 McGraw-Hill Higher Education. All rights reserved.
Fat Loading
• Idea was it would provide a better energy
source since fat is the most concentrated
form of energy
• It did not work
© 2007 McGraw-Hill Higher Education. All rights reserved.
Ideal Body Weight
• Height/weight charts
– Not most accurate; don’t take body type into account
• Body Mass Index (BMI)
– Considers age, gender, height, and weight
• Fat weight vs. nonfat weight = body composition
• Health and performance may be the best indicator
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Lean tissue or lean body weight
– Weight made up of bone, muscle, tendon, and
connective tissue
• Percent of body fat
– The percent of the body weight made up of fat
• Body composition is the relationship
between fat tissue and lean body tissue
Average
Female
20-25%
Should not be
below
12%
Male
12-15%
5%
Healthy
5-18%
12-25%
© 2007 McGraw-Hill Higher Education. All rights reserved.
Assessing Body Composition or
Percent Body Fat
• Several methods
– Hydrostatic or Under water weighing
• Gold standard
– Bioelectrical impedance
• Measures electrical current going through body
– Skinfold thickness measures
• 3-5% error, must practice
© 2007 McGraw-Hill Higher Education. All rights reserved.
© 2007 McGraw-Hill Higher Education. All rights reserved.
Assessing Caloric Balance
• Caloric balance = Calories consumed - calories expended
• Positive caloric balance results in weight gain
• Negative caloric balance results in weight loss
• Calories are lost or expended in 3 ways:
– Basal metabolic rate (calories burned at rest)
– Work/exercise (activities using more energy than sleep)
– Excretion (losing some calories going to the bathroom)
© 2007 McGraw-Hill Higher Education. All rights reserved.
–
–
–
–
Carbohydrate = 4 calories/gram
Protein = 4 calories /gram
Fat = 9 calories/gram
Alcohol = 7 calories/gram
(macronutrient)
(macronutrient)
(macronutrient)
(not a macronutrient)
– Nutrition labels are based on 2000 calorie diet
– College athletes consume 2000-5000 calories/day
– Endurance athletes may consume as many as 7000
calories
© 2007 McGraw-Hill Higher Education. All rights reserved.
Methods of Weight Loss
• exercise and good diet to lose weight
• Only doing 1 is not long term solution
• Dieting alone results in lean body tissue loss
– Should not drop below 1000-1200 calories for
women and 1200-1400 for men
• Exercising will
– Decrease fat mass
– Increase muscular strength and endurance,
cardiorespiratory endurance, and flexibility
© 2007 McGraw-Hill Higher Education. All rights reserved.
• The key is moderation
–
–
–
–
A combination of dieting and exercise
A negative energy balance must be achieved
Lose no more than 1-2 pounds per week
Weight loss of more than 2 pounds is
dehydration or water loss
• 1 pound = 3500 calories
© 2007 McGraw-Hill Higher Education. All rights reserved.
Methods of Weight Gain
• Want to increase lean body mass (muscle)
• Increased physical activity and diet
• Approximately 2500 calories is required per
pound of lean body mass, an increase 5001000 calories per day
• A 1-2 pound per week gain is adequate
© 2007 McGraw-Hill Higher Education. All rights reserved.
Disordered Eating
• Epidemic in our society, especially in sports
• 1 out of 200 girls age 12-18 will develop
some pattern of eating disorder (1-2% of
population)
• Bulimia Nervosa
– Commonly females - ranging in age from
adolescence to middle age
– Periods of starvation, bingeing (thousands of
calories) and purging through vomiting, fasting
and laxatives/diuretics
© 2007 McGraw-Hill Higher Education. All rights reserved.
– Characteristics
• Typically bulimic athletes are white, middle to
upper-middle class
• Perfectionist, obedient, overcompliant, highly
motivated, successful academically, well-liked, and
a good athlete
• gymnastics, track, dance
• occasionally seen in male gymnasts and wrestlers
– Bingeing and purging can result in stomach
rupture, heart rhythm, liver damage, tooth
decay from acids, chronically inflamed mucous
lining of mouth and throat
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Anorexia Nervosa
– 30-50% of anorexics also suffer from bulimia
– Characterized by distorted body image and
constant concern about weight gain
– Impacts mostly females
– Starts often with adolescents and can be life
threatening
– While the athlete tends to be too thin they
continue to feel fat
– Deny hunger and are hyperactive
– Highly secretive
© 2007 McGraw-Hill Higher Education. All rights reserved.
• Early intervention is critical with eating
disorders
– Empathy is a must
• Psychological counseling is key
• Must have athlete recognize the problem,
accept the benefits of assistance and must
voluntarily accept help for treatment to
work
© 2007 McGraw-Hill Higher Education. All rights reserved.
Female Athlete Triad
• Potentially fatal problem involving a
combination of disordered eating,
amenorrhea, and osteoporosis
• Incidence is uncertain
– Eating disorders may be as high as 62% in
some sports
– Amenorrhea may be top out at least 60%
• Major risk is the resultant loss of bone mass
that can’t be regained
© 2007 McGraw-Hill Higher Education. All rights reserved.