Chapter 2 1933 British Medical Association Basic 11 Basic 7 (1940s)(1941 RDA) Basic 4 (1950s) Food...

Post on 15-Jan-2016

223 views 0 download

Tags:

Transcript of Chapter 2 1933 British Medical Association Basic 11 Basic 7 (1940s)(1941 RDA) Basic 4 (1950s) Food...

Chapter 2 1933 British Medical Association

Basic 11 Basic 7 (1940s)(1941 RDA) Basic 4 (1950s) Food Pyramid (1990)

1990 Nutrition Labeling & Education Act 1997 DRI’s

Chapter 2 FDA - Responsible for food

labeling USDA - Labeling of meat & poultry

(certifies foods as organic) FTC - Regulates advertising of FDA

& USDA

Chapter 2 New Terms since 1990

Enriched-More than it had originally Fortified-Pre-processed amounts Essential-Body can’t produce-must go

to an outside source. Fat Free - less than .5gms/serving Light ( 50% less than normal)

Chapter 2 Reduced Calorie (25% less than normal) Calorie Free - less than .5cal/serving Organic - Without pesticides Natural - “Little Processing”

Chapter 2 CARBOHYDRATE 55-60%

Simple 15% Monosaccharide

Fructose, honey, glucose Disaccharide

Table sugars Complex 35-50%

Rice, Pasta, Beans, Starches

CARBOHYDRATE LOADING-CLASSICAL

Day 1: exhaustive exercise to deplete CHO

Days 2-4: low CHO diet (higher protein and fat; 60-100 g of CHO), moderate training

Days 5-7: high CHO diet (400-700 g)

Competition: high CHO precompetition meal

CARBOHYDRATE LOADING-PRACTICAL Day 1: train at around 85-90% of

maximal HR. Days 2-6: gradually taper training. Days 1-3: CHO diet of around 50%

CHO. Days 4-6: Increase diet to around

80% CHO.

PROBLEMS WITH LOADING Classical: increased cholesterol,

more urea, gas, increased water weight, GI troubles, less effective each time.

Practical: some increased weight (1 g of glycogen has 2.7 g of water)

POST EXERCISE CHO 50-75 g of moderate to high

glycemic CHO every 2 hours for a total of 7-10 g/kg of body weight.

Only 5% of glycogen stores are replenished per hour.

Protein PROTEIN 10-15%

Amino Acids- 9 are essential peptides Kwashiorkor

The process of making new amino acids by shifting nitrogen groups is termed transamination.

The catabolism of protein into urea and other substances is termed deamination.

Protein About 65% of total protein in the

body is found in muscle (12-15% of body mass)

Also found in bone, hemoglobin and myoglobin, insulin, hair, enzymes

It is also used for energy (gluconeogenesis) when carbohydrate levels are low

Protein Anaerobic and aerobic athletes may

need more—up to 1.8 g/kg of body weight

After heavy workouts, glutamate is converted to glutamine to be carried by the blood to the liver for degradation from ammonia to urea (with the backbone helping to form glucose)

FAT FAT

No more than 30% Saturated-No more than 10% Polyunsaturated Monounsaturated Omega 3 Fatty Acids & Omega 6 Trans Fatty Acids

To lose 1 pound of fat you must have a caloric deficit of _____ calories

Chapter 2 Accounting for Digestive Efficiency

(Atwater) The following are derived by a bomb

calorimeter: Protein = 5.65 kcal Carbohydrate = 4.2 kcal Fat = 9.45 kcal

The coefficient of digestibility are 4,4 &9

Micronutrients VITAMINS Fat Soluble

Stored in fat and liver, so daily intake not needed. If on a very low fat diet, may need to supplement.

A (Night Vision) Used for night vision. A precursor of vitamin A is beta carotene, which acts as an anti-oxidant. Retinol is found in milk, butter, and cheese, while beta carotene is found in green and yellow/orange veggies.

Vitamin D (Synthesized from sun) Aids in the absorption of calcium for bones,

teeth, and muscle contraction. If deficient may develop Rickets

Vitamin E Aphrodisiac, skin, cell membranes, anti-

oxidant Vitamin K

Intestional Flora, Blood Clotting

Too much With the fat soluble vitamins,

overdosing usually has negative side effects like diarrhea and nausea. Death is possible with too much vitamin A.

WATER SOLUBLE VITAMINS Vitamin C and the B-complexes Act mainly as coenzymes (part of an

enzyme) in metabolism. Overdoses are rare (since excess is

excreted in urine), but some problems exist.

Minerals 22 Major & Minor – If lacking you

may become a Pica-Eater Provide structure (bones and teeth) Maintain heart rhythm, muscle

contractility, neural conductivity, and acid-base balance.

Regulate cellular metabolism (enzymes/hormones)

SODIUM, POTASSIUM, CHLORINE Electrolytes necessary for muscle

contraction, nerve conduction, and fluid exchanges across membranes.

Some individuals are sodium sensitive, resulting in higher blood pressures.

IRON Traps the oxygen in hemoglobin. Hard to absorb; phenols in coffee and

tannins in tea block absorption. Ascorbic acid helps absorption of non-heme iron.

Possible “sports anemia” Ways to lose iron: bleeding, menstrual

cycle, coffee/tea Increase absorption: ascorbic acid, use

iron skillets

Eating Disorders

Anorexia Nervosa A crippling obsession with body

size, with a relentless pursuit of thinness.

Usually begins with dieting; food restriction eventually becomes obsessive

Anorexia Nervosa Preoccupation with being “too fat” Loss of menstrual cycle Frequent comments about body

weight or shape Significant body weight loss Body weight too low for athletic

performance

AMENORRHEA A cessation of the menstrual cycle, or

irregular menstrual cycle (oligomenorrhea) Occurs in up to 40% of athletic population

(vs. 2-5% in normals) Interplay of physical, nutritional, genetic,

hormonal, regional fat distribution, psychological, and environmental factors.

Cessation of the menstrual cycle can lead to a decrease in estrogen, with an increased risk of osteological injury.

BULIMIA NERVOSA Consumption of calorie dense

foods (usually late at night), followed by some method(s) of purging: Vomiting Laxatives Diuretics Compulsive exercising

BULIMIA NERVOSA Pretty much a learned trait from

peers/television/movies Lifelong dependence possible if

laxatives used to purge

BINGE EATING DISORDER Unlike bulimia, there is no purging. Binge eating takes place in private

with feelings of guilt, depression, or self-disgust.

Chapter 2 Pregame meal

500 to 1000 kcal from primarily complex carbohydrates.

Percentage of body fat: 10-20% men 15-25% female

Chapter Basal Metabolic Rate vs. Resting

Metabolic Rate Set Point Theory of Metabolism Thermic effects:

Rest = 60-75% Activity = 15-30% Food = 10%

Chapter Assessing body composition

Circumference Ht/Wt + Frame size Skinfold Calipers

HarpendenLangSlimguide

Chapter Futrex 5000 BIA – Bioimpedence Bod Pod DEXA Classifications of

Overweight/Obesity Overweight = BMI 25-29.9 Obesity = BMI 30 or higher

Chapter Morbid Obesity = 100 pounds or more

over weight Hyperplasia of fat cells

Last trimester of pregnancy First year of life During Puberty Fourth time???