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ENERGYENERGY

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Calorie - used as standard unit for measuring the energy value of food- amount of heat necessary to raise 1 gram of water by 1�C ◦measures human energy expenditures

1 Kcal = 4.184 kilojoules (KJ)1000 KJ = 1 megajoule (MJ)1000 Kcal = 4.184 MJ1 MJ = 239 Kcal

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Methods of Energy Methods of Energy MeasurementMeasurement

Direct calorimetryMeasures amount of energy expended by

monitoring heat productiona. Bomb calorimeter – heat of combustion =

gross energy value of foodb. Respiration chamber – heat released from

a person’s body determine how much energy each activity has burned for that person

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Indirect calorimetry◦Measured by determining with a respirometer

the oxygen consumption and carbon dioxide production of the body in a given period of time

Volume of CO2 Eliminated

RQ = ————————————Volume of O2 Consumed

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Indirect Calorimeter- Atwater (physiologic fuel value of food)

Energy PathwaysEnergy PathwaysGlycolysis – major pathway of CHO

metabolism; 1 glucose 2 pyruvate anaerobic

Pyruvate acetyl CoA

TCA cycle additional ATP and Carbon dioxide

Electron transport chain Water

WMSU BSND Review 2007

GlucoseGlucoseThe fate of pyruvate

◦Anaerobic vs. aerobic pathways

Occurs in the cytoplasmPyruvic acid & ATP

Sprint activity

Occurs in the mitochondria CoA (Pyruvic acid +Coenzyme)Aerobic exercise

GlucoseGlucose

The fate of pyruvate ◦AnaerobicPyruvate-to-lactic acid◦Cori cycle

GlucoseGlucoseThe fate of pyruvate

◦AerobicPyruvate-to-acetyl CoA

Glycerol & Fatty Glycerol & Fatty AcidsAcids

Fatty acids-to-acetyl CoA◦Beta-oxidation (mitochondria)

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Amino AcidsAmino AcidsAmino acids-to-acetyl CoA

WMSU BSND Review 2007

Amino AcidsAmino AcidsDeamination

◦Keto acid◦Ammonia

Amino AcidsAmino AcidsTransamination

Amino AcidsAmino Acids Ammonia- to-urea

Urea excretion via the kidneys

Economics of FeastingEconomics of Feasting

Excess protein

Excess carbohydrate

Excess fat

Economics of FeastingEconomics of Feasting

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Economics of FastingEconomics of Fasting

Economics of FastingEconomics of FastingGlucose needed for the brain

Protein meets glucose needs

Economics of FastingEconomics of FastingShift to ketosis

Economics of FastingEconomics of FastingSuppression of appetite

Slowing of metabolism

Symptoms of starvation

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Energy BalanceEnergy Balance

Weight Stability:Energy intake balances with energy out

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Energy BalanceEnergy Balance Overweight and obesity result from

an energy imbalance

Body weight is the result of genes, metabolism, behavior, environment, culture and socio-economic status

Behavior and environment play a large role causing people to be overweight and obese (greatest areas for prevention and treatment actions)

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Positive & Negative Positive & Negative Energy BalanceEnergy Balance

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Energy IntakeEnergy IntakeWhat regulates our food intake?

◦ Hunger Prompts eating; physiological desire

Hypothalamus: center that control activities such as maintenance of water balance, temperature regulation, appetite control

◦ Appetite The integrated response to the sight, smell,

thought or taste of food that initiates or delays eating

◦ Satiation Feeling of satisfaction and fullness that occurs

during a meal signals to stop eating◦ Satiety

Feeling of satisfaction that occurs after a meal; inhibits eating until the next meal

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A Cascade of Regulation: HungerAppetiteSatiation and Satiety

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Satiety hormone?Satiety hormone?Leptin

▪ An appetite-suppressing hormone

▪ Produced by adipose tissue▪ Travels to the brain▪ Directly linked to appetite and

body fatness▪ Gain of body fatness stimulates

leptin production (reduces food consumption resulting in fat loss)

▪ Loss of body fat reduces leptin secretion (increasing appetite)

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HYPOTHALAMUSHYPOTHALAMUSThe main function is homeostasisReceives inputs about the state of the

bodyDozens of chemical participate in

appetite control and energy balance▪ Neuropeptide Y ▪ causes CHO cravings ▪ initiates eating ▪ decreases energy expenditure ▪ increases fat storage

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COMPOSITION OF FOODS/MEALS COMPOSITION OF FOODS/MEALS IMPACTS SATIATION AND SATIETYIMPACTS SATIATION AND SATIETY

Protein – most satiating; may account for the popularity of high-protein weight loss diet

Complex CHO/Fibers – fill stomach, delay absorption of nutrients

Fat – weaker impact on satiation, however, in the intestine secretes CCK which signals satiety

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Energy ExpenditureEnergy ExpenditureEnergy Out: Components of Energy

Expenditure◦Basal Metabolism (BMR)◦Physical Activity (PA)◦Thermic Effect of Food (TEF)

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Basal Metabolic RateBasal Metabolic Rate

Basal metabolism – is the basic essential metabolic processes by the body at rest also defined as the minimum amount of energy required to carry out vital processes.

Basal metabolic rate – the amount of energy required for basal metabolic processes per unit of body weight per unit of time.

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BMR

Male = 1 kcal/kg IBW/hrFemale = .95 kcal/kg IBW/hr

Example: IBW 56 kg, FemaleBMR = .95 kcal x 56 x 24 hrs.

= 1276.8 kcal/day

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Energy ExpenditureEnergy Expenditure

BMR: 60 to 65%

PA: varies from individual

TEF: 10%

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Energy Balance: Energy Balance: Energy ExpenditureEnergy Expenditure

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Increase BMRIncrease BMR Decrease BMRDecrease BMR

Fever * StressTotal body weightSmoking * CaffeineHigh Lean Body Mass Rapid growthHot & cold ambient

tempPregnancy, lactationHyperthyroidismLarge body surface

area

AgingFemaleFasting/StarvationSleepHypothyroidism

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Physical activityPhysical activity

-Voluntary movement of the muscles and the support system

Types of activity % kcal/kg

Bedridden 25Sedentary (light) 30Moderate (active) 35Very active (heavy) 40Strenuous 45

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Example: Female, IBW = 56 kgs. BMR = 1276.8 kcal/day Activity = Light activity (30%)

PA = BMR x Activity = 1276.8 kcal/day x 30%= 383.04 kcal/day

Thermic Effect of Food (TEF or DIT)- estimate energy requirements of processing of food.

- on usual mixed diet- 6 to 10 % total energy expenditure for basal and physical activity- high protein diet – 15%- high fat and carbohydrate diet – 5%

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Energy Balance: Body Energy Balance: Body WeightWeight

Body Mass IndexBMI = weight (kg)

height (m)2

or

BMI = weight (lb) x 703 height (in)2

Healthy weight is 18.5 to 24.9 (WHO, 1979)

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Table 6. Proposed BMI Classification by Table 6. Proposed BMI Classification by

FAO/WHO (RENI, 2002)FAO/WHO (RENI, 2002)

ClassificationClassification BMI (kg/mBMI (kg/m22)) Risk of co-morbidities Risk of co-morbidities

UnderweightUnderweight < 18.5 Low

Normal Normal RangeRange

18.5 – 24.9 Average

OverweightOverweight 25.0-29.9 Increased

Obese Obese 30-39.9 Moderate

Extreme Extreme obeseobese

> 40 Severe

Estimating Energy RequirementEstimating Energy Requirement

Calculate the IBW using the tannhauser’s formula

Calculate the BMRCalculate the Physical ActivityCalculate the TEFCalculate the TER

1. IBW (Ideal BodyWeight)1. IBW (Ideal BodyWeight)

Steps:a. take height into cmb. Subtract the factor 100 and the result is the ideal body weight in kilograms (large frame)c. subtract 10% for medium frame (Filipinos)d. subtract another 10% for small frame

Note: do not round off the answer.

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Limitations of BMILimitations of BMI

BMI does not reflect body fatMay misclassify people (muscular)Used to reflect disease risksReflects height and weight – not body

composition

BMI = 31 Is this obese???

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BODY FAT/BODY COMPOSITIONBODY FAT/BODY COMPOSITION

Men and women vary in body composition

. Men typically have greater lean mass

. Women have greater body fat

. Normal Body Fat. Men – 12-20%. Women – 20-30%

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Energy MetabolismEnergy Metabolism

Glycogenesis (glucose to glycogen)Glycogenolysis (glycogen to glucose)Gluconeogenesis (amino acids to

glucose)Lipogenesis (glucose or FAAs to fats)Lipolysis (fats to FAAs & glycerol)

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Metabolic Energy Production: Metabolic Energy Production: Review & OverviewReview & OverviewReactants: glucose

◦Glycogen, FAAs◦Amino acids

PhosphorylationGlycolysis–cytoplasm

◦2 ATPs, anaerobicCitric Acid Cycle-2 ATPs, mitochondria,

aerobicElectron Transport systemHigh energy e-, 32 ATPs

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Fat MetabolismFat Metabolism

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Pancreatic Hormones, Insulin & Pancreatic Hormones, Insulin & Glucagon Regulate MetabolismGlucagon Regulate Metabolism

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NUTRITION AND ALCOHOLNUTRITION AND ALCOHOL

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AlcoholAlcohol Class of organic compounds with hydroxyl groups (OH) Examples of alcohol:

H

H – C – OH

H – C – OH

H – C – OH

H

Glycerol: component of triglycerides

H

H – C – H

H – C – H

OH

Ethanol or Ethyl Alcohol: alcohol found in beer, wine, distilled spirits

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Facts About EthanolFacts About Ethanol

1 g ethanol = 7 kcal without additional nutrients

Medically defined as a depressant drug when taken in low levels euphoric effect

could dissolve lipids in cell membranes rapidly enter cells

Production of ethanol: anaerobic metabolism of CHO by microorganisms

“ proof” : amount of ethanol stated in distilled liquors

100 proof = 50% ethanol 80 proof = 40% ethanol

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Facts About AlcoholFacts About Alcohol

1 alcoholic drink contains ½ oz of pure ethanol

4-5 oz wine10 oz wine cooler12 oz beer

1 ¼ oz distilled liquor (80 proof- whiskey, scotch, rum,

vodka)

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Digestion, Metabolism and Digestion, Metabolism and UtilizationUtilization

A. In the Stomach- no digestion needed, quickly absorbed

- if stomach is empty, then 20% directly absorbed through gastric lining

- Alcohol absorption is minimized in the presence of food

- Alcohol in stomach breakdown by alcohol dehydrogenase

* Women produce less alcohol dehydrogenase

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B. In the Duodenum- Alcohol readily absorbed and metabolized compared to other nutrients transported through intestinal veins and capillaries to the liver

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C. In the Liver - Liver produces alcohol

dehydrogenase that oxidizes alcohol- Normally: liver breaks and uses fatty acids as its energy source- in the presence of alcohol, liver metabolize alcohol first instead of fat- Liver can process ½ oz of ethanol per our

alcohol consumed > available enzymes, extra alcohol circulates throughout the body

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Table 1. Effects of Alcohol on the BrainTable 1. Effects of Alcohol on the Brain

Blood R-OH Conc. Effect on Brain

0.05 Impaired judgment, relaxed inhibitions, altered mood, increased heart rate

0.10 Impaired coordination, delayed reaction time, exaggerated emotions, impaired peripheral vision, impaired ability to operate a vehicle

0.15 Slurred speech, blurred vision, staggered walk, seriously impaired coordination and judgment

0.20 Double vision, inability to walk

0.30 Uninhibited behavior, stupor, confusion, inability to comprehend

0.40-0.60 Unconsciousness, shock, coma, death due to cardiac or respiratory failure

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Table 2. Alcohol Doses and Blood LevelsTable 2. Alcohol Doses and Blood Levels

No. of Drinks

Percentage of blood alcohol

by body weight

100 lbs 120 lbs 150 lbs 180 lbs 200 lbs

2 0.08 0.06 0.05 0.04 0.04

4 0.15 0.13 0.10 0.08 0.08

6 0.23 0.19 0.15 0.13 0.11

8 0.30 0.25 0.20 0.17 0.15

12 0.45 0.36 0.30 0.25 0.23

14 0.52 0.42 0.35 0.34 0.27

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Table 3. Health Effects of Alcohol Table 3. Health Effects of Alcohol ConsumptionConsumption

What is the health problem?

What is the effect of alcohol?

Arthritis Increased risk of having gout

Cancer Increased risk of cancer of the liver, rectum, breast, pancreas, mouth, throat: very harmful when combined with tobacco or nicotine

Fetal alcohol syndrome Causes permanent physical, behavior, mental abnormalities in the fetus

Heart Disease Raises blood pressure, blood lipids, and increased risk for stroke

Diabetes May increase or decrease blood glucose levels

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Table 3. Health Effects of Alcohol Table 3. Health Effects of Alcohol ConsumptionConsumption

What is the health problem?

What is the effect of alcohol?

Kidney problems Enlarges the kidneys

Liver disease Fatty liver, cancer of the liver

Malnutrition Increased risk of having PEM and other vitamin/mineral deficiencies

Nervous disorders Causes dementia, impairs balance and memory

Obesity Increased energy intake

Psychological disturbances Causes depression, anxiety and insomnia

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Table 4. Myths and Truths about Table 4. Myths and Truths about AlcoholAlcohol

Myths Fact

Alcohol warms the body. Blood is momentarily diverted to skin overall effect is a cooling one

Wine and beer do not lead to addiction.

Substance abuse is directly related to amounts consumes and is not dependent on the kind of alcoholic beverage consumed

Mixing drinks gives a hangover.

Excessive alcohol intake of any kind results in a hangover

Walking will “sober up” a person.

Alcohol metabolism is time-dependent. Only liver cells not muscle cells can metabolize alcohol

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Table 4. Myths and Truths about Table 4. Myths and Truths about AlcoholAlcohol

Myths Fact

Caffeine offsets the effects of alcohol.

Caffeine is a stimulant but will not speed up alcohol metabolism

Driving coordination is still impaired after a night of drinking. Allow at least 24 hours for alcohol to be metabolized completely

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NUTRITION NUTRITION AND AND

PHYSICAL FITNESSPHYSICAL FITNESS

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Physical FitnessPhysical Fitness

A set of abilities individuals possess to perform specific types of physical activity

Physically fit individuals have energy for both planned and unplanned activities at home or the workspace

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Physical FitnessPhysical Fitness

Physical Activity can be classified as:◦Unstructured physical activityUsual activities of daily life

◦Structured physical activityPlanned program designed to improve physical fitness

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Physical FitnessPhysical Fitness

Benefits of physical fitness:◦Restful sleep◦Nutritional health◦Optimal body composition◦Optimal bone density◦Lower incidence of anxiety and depression◦Improves self image◦Improves circulation and lung function

"Those who do not find time for exercise will have to find time for illness." ~ Earl of Derby

Excessive Exercise Risks

ChildrenEnergy needs not achieved and limited growth and development

TeensInadequate energy intakeDietary protein used for energyAmenorrheaNegative calcium balance and reduced bone massSports anemia

AdultsPossible increased need for riboflavin and vitamin B6Exercise-related injuries

Pregnant WomenLow weight gainLow-birth-weight infant

Nursing mothersExcessive rate of weight loss, reducing milk production and limiting the infant growth

Older adultsExercise-related injuries leading to disability

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Components of FitnessComponents of Fitness

Flexibility – ability to bend and recover without injury

Muscle strength – ability of ,muscles to work against resistance

Muscle endurance – ability of muscle to contact repeatedly without being exhausted

Cardio-respiratory endurance – ability to perform large muscle dynamic exercise of moderate to high intensity for prolonged periods.

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Basic Elements of the Exercise Basic Elements of the Exercise PrescriptionPrescription

FrequencyIntensityTimeModeRate of Progression

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FrequencyFrequencyNumber of days per week

Hard/Easy principle

Active rest

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IntensityIntensity

Initial levels of fitness determine at what intensity a client should begin with.

Methods of determining intensity:◦% of Maximum heart rate◦heart rate reserve◦Perceived Exertion

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TimeTime

ACSM recommendation: “ every individual should accumulate 30 minutes or more of moderate physical activity on most , but preferably all days of the week”.

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ModeModeWhat the client likes or will do!Health and weight loss should involve

using large muscle groups.Weight bearing exercise for

strengthening bones.Specific exercise for performance.Swimming is not great for weight loss.

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Rate of ProgressionRate of Progression3 stages:

◦initial conditioning stage-4 weeks.◦improvement stage- 4 to 5 months.◦maintenance stage- begins 6 months after

start, can last a lifetime!

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Exercise PrescriptionExercise Prescription

Simultaneous increase in any 3 elements may overload the individual's physiological system increasing risk to exercise-related injuries and exercise burn out

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Stages of Progression in Stages of Progression in Exercise ProgramExercise Program

Stages:◦Initial Conditioning

◦Improvement

◦Maintenance

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Factors Related to Exercise Factors Related to Exercise Program AdherenceProgram Adherence

Biological Factors

Relative body fat

Overweight

Psychological Factors

Self motivation

Self efficacy

Attainment of exercise goals

Depression/anxiety/introversion

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Factors Related to Exercise Factors Related to Exercise Program AdherenceProgram Adherence

Social Factors

Family Support

Family Problems

Exercise/job Conflicts

Income and education levels

Behavioral Factors

Smoking

Leisure time

Credit training

Type A behavior prone

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Factors Related to Exercise Factors Related to Exercise Program AdherenceProgram Adherence

Program Factors

Social support

Location and convenience of exercise facility

Exercise leadership and supervision

Initial exercise intensity

Variety of exercise modes

Program costs

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Strategies to Increase Exercise Strategies to Increase Exercise Program AdherenceProgram AdherenceProgram Strategies

◦Offer both group and individual activities

◦Select time and locations that are convenient

for program participants

◦Offer variety of exercise and fitness activities

◦Monitor the progress of program participants

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Strategies to Increase Exercise Strategies to Increase Exercise Program AdherenceProgram AdherenceProgram Strategies

◦Set realistic short-term and long-term goals for

each participants

◦Educate participants about exercise, physical

fitness and health benefits

◦Provide incentive for exercise

◦Encourage social support

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Strategies to Increase Exercise Strategies to Increase Exercise Program AdherenceProgram Adherence

Behavioral Strategies for Exercise Leaders◦Be a positive role model

◦Show interest in participants

◦Exhibit enthusiasm

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Strategies to Increase Exercise Strategies to Increase Exercise Program AdherenceProgram Adherence

Behavioral Strategies for Exercise Leaders◦Develop good rapport with each participant

◦Motivate and encourage

◦Attend to orthopedic and musculoskeletal

problems of participants

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Importance of Importance of Nutrition in PerformanceNutrition in PerformanceInadequate intake of essential nutrients

impair performance due to:◦Inadequate energy supply◦Inability to regulate exercise metabolism at

an optimal level◦Decreased synthesis of key body tissues or

enzymes

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Importance of Importance of Nutrition in PerformanceNutrition in Performance

Excessive intake of essential nutrients impair performance results to:◦Increased proportions of body fat◦Poor athletic performance◦Increased risk of developing diseases◦Toxicity symptoms

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Energy Requirements Energy Requirements During PerformanceDuring Performance

Thermic Effect of

Food

Basal Metabolism

Physical Activity

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How the Body Stores EnergyHow the Body Stores Energy

Glycogen in liver

Fat in adipose Tissues

Glycogen is used to top-up the blood

glucose level

Majority of glycogen is stored

in muscles

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How the Body Stores EnergyHow the Body Stores Energy

Exercise converts stored energy to kinetic energy and heat

Muscles use energy at a rate directly proportional to the rate and intensity of the activity or exercise

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Factors that Influence Factors that Influence Fuel ChoicesFuel Choices

1. Fuel availability from the diet

2. Intensity and duration

3. Degree to which the body is conditioned to perform the activity

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Intensity and DurationIntensity and Duration

Activity Intensity

Activity Duration

Preferred Source

Fuel Oxygen Needed

Activity Example

Extreme < 30s ATP NO Shot put

Very High 30s – 3m Carb NO ¼ mile run

High3 - 20m

Carb and some fats

YEScycling,

swimming

Moderate> 20m

Fat and some carbs

YES hiking

FLUID INTAKE

The following are the guidelines to ensure adequate fluid replacement, leading to optimal performance

a. Eat a nutritionally balanced diet and drink adequate fluids during the 24-hour period before an event

b. Consume 2 cups of fluid 2 hours before exercise followed by another 2 cups 15 to 20 minutes before exercise and 4 to 6 oz fluid every 10 to 15 minutes during exercise.

c. Drink cool beverages to reduce body core temperature.

d. Consume sports drink to enhance fluid intake and absorption and help delay fatigue in endurance events lasting longer than 1 hour.

e. After exercise, consume sports drink to enhance palatability and further promote fluid replacement.