Energy Balance and Energy Balance and Body CompositionBody Composition

Energy Balance

•Type of energy•Amount at

one time•Timing of meals•Energy stored

in body

Energy INTAKE

•Metabolism•Daily Activity•Exercise-type and intensity•Thermal effect

of meals

Energy Expenditure

Energy intake

Type of energy: ie.. Quality of energy intake Carbohydrate vs Fat

Amount at one time: i.e. Quantity of energy intake All at once vs small amounts

Timing of Meals: Early vs late

Energy Stores; Glycogen reserve in Liver and Muscle

Energy In: The kCalories Energy In: The kCalories Foods ProvideFoods Provide

Food Intake; Regulated byFood Intake; Regulated by– Appetite Appetite initiates eating through the sight, initiates eating through the sight,

smell, thought or taste of food.smell, thought or taste of food.–

– HungerHunger is the feeling that motivates us to is the feeling that motivates us to eat and is controlled by the hypothalamus.eat and is controlled by the hypothalamus.

– SatiationSatiation is the feeling of satisfaction and is the feeling of satisfaction and fullness that causes us to stop eating.fullness that causes us to stop eating.

– SatietySatiety reminds us not to eat again until reminds us not to eat again until the body needs food.the body needs food.

Energy In: The kCalories Energy In: The kCalories Foods ProvideFoods Provide

Food IntakeFood Intake– Overriding Hunger and SatietyOverriding Hunger and Satiety

Stress eating is eating in response to arousal.Stress eating is eating in response to arousal. Cognitive influences such as perceptions, Cognitive influences such as perceptions,

memories, intellect, and social interactionsmemories, intellect, and social interactions

– Sustaining Hunger and SatietySustaining Hunger and Satiety Protein is the most satiating.Protein is the most satiating. Complex carbohydrates are satiating.Complex carbohydrates are satiating. High-fat foods stimulate and entice people to High-fat foods stimulate and entice people to

eat more.eat more.

Energy In: The kCalories Energy In: The kCalories Foods ProvideFoods Provide

Food IntakeFood Intake– Message Central—The

Hypothalamus Integrates messages about energy

intake, expenditure, and storage

Energy ExpenditureEnergy Expenditure

Metabolism: Age, gender, body composition, diet, exercise, stress, disease, drugs

Daily Activity: Sedentary daily life activities vs busy or active life

Exercise: Aerobic vs Resistant training, Duration and intensity

Thermal Effect of Meals: Type and Number of Meals

Ph

ysic

al A

cti

vit

y

Energy Out: The kCalories Energy Out: The kCalories the Body Expendsthe Body Expends

Components of Energy ExpenditureComponents of Energy Expenditure– Basal MetabolismBasal Metabolism (basal metabolic (basal metabolic

rate, BMR)rate, BMR) 2/3 of energy2/3 of energy expenditure expenditure For For most sedentary individualsmost sedentary individuals

Supports the basic processes of lifeSupports the basic processes of life

Resting metabolic rate (RMR) is a Resting metabolic rate (RMR) is a measure of energy slightly higher measure of energy slightly higher than BMRthan BMR..

Energy Out: The kCalories Energy Out: The kCalories the Body Expendsthe Body Expends

Components of Energy ExpenditureComponents of Energy Expenditure– Basal Metabolism - Factors affecting Basal Metabolism - Factors affecting

BMRBMR Aging slows BMRAging slows BMR Height – the taller, the higher the BMRHeight – the taller, the higher the BMR Growth increases BMR.Growth increases BMR. Body composition (lean body mass increases BMR)Body composition (lean body mass increases BMR) Fever increases BMR.Fever increases BMR. Stress increases BMR.Stress increases BMR. Environmental temperature - both heat and cold Environmental temperature - both heat and cold

raise BMRraise BMR

Energy Out: The kCalories Energy Out: The kCalories the Body Expendsthe Body Expends

Components of Energy ExpenditureComponents of Energy Expenditure– Basal Metabolism - Factors affecting Basal Metabolism - Factors affecting

BMRBMR Fasting/starvation slows BMR. (Dieting)Fasting/starvation slows BMR. (Dieting) Malnutrition slows BMR.Malnutrition slows BMR. HormonesHormones

– Thyroid hormones can increase or decrease Thyroid hormones can increase or decrease BMR.BMR.

– Premenstrual hormones can increase BMR.Premenstrual hormones can increase BMR. Smoking increases BMR.Smoking increases BMR. Caffeine increases BMR.Caffeine increases BMR. Sleep slows BMR.Sleep slows BMR.

Energy Out: The kCalories Energy Out: The kCalories the Body Expendsthe Body Expends

Components of Energy ExpenditureComponents of Energy Expenditure– Physical activityPhysical activity

Most variable and changeableMost variable and changeable

VoluntaryVoluntary

It can be significant in weight loss and It can be significant in weight loss and weight gain.weight gain.

Duration, frequency and intensity Duration, frequency and intensity influence energy expenditure.influence energy expenditure.

Energy Out: The kCalories Energy Out: The kCalories the Body Expendsthe Body Expends

Components of Energy ExpenditureComponents of Energy Expenditure– Thermic effect of foodThermic effect of food (TEF) is estimated at (TEF) is estimated at

10% of total energy intake and involves 10% of total energy intake and involves digestion and absorption.digestion and absorption. Carbohydrate 5-10%Carbohydrate 5-10% Fat 0-5%Fat 0-5% Protein 20-30%Protein 20-30% Alcohol 15-20%Alcohol 15-20%

– Adaptive thermogenesisAdaptive thermogenesis is the adjustment is the adjustment in energy expenditure related to environmental in energy expenditure related to environmental changes.changes.

Energy Out: The kCalories Energy Out: The kCalories the Body Expendsthe Body Expends

Estimating energy requirements is Estimating energy requirements is affected by many factors.affected by many factors.– GenderGender – men generally have a higher BMR – men generally have a higher BMR– GrowthGrowth – BMR is high in people who are – BMR is high in people who are

growinggrowing– AgeAge – BMR declines as lean body mass – BMR declines as lean body mass

decreasesdecreases– Physical activityPhysical activity – Activities are clustered by – Activities are clustered by

intensity and vary considerablyintensity and vary considerably– Body composition and body sizeBody composition and body size – –

taller people have more surface area and taller people have more surface area and heavier people have higher BMRsheavier people have higher BMRs

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Current weight standards use Current weight standards use height and weight data and height and weight data and do not do not take body compositiontake body composition into into consideration. consideration.

These may be misleading.These may be misleading.

Changes 1980-2000Changes 1980-2000

No Data14.446.01976 to 1980

2.923.056.01988 to 1994

4.730.564.51999 to 2000

Severe Obesity

(BMI > 40)

Obesity(BMI > 30)

Overweight(BMI > 25)

Increase in Prevalence (%) of Overweight (BMI >or= 25),

Obesity (BMI >or=30) and Severe Obesity (BMI >or=40) Among U.S. Adults.

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Defining Healthy Body WeightDefining Healthy Body Weight– The Criterion of FashionThe Criterion of Fashion

Society values change over time.Society values change over time. Perceived body images Perceived body images

– The Criterion of Health The Criterion of Health Good health supercedes appearance.Good health supercedes appearance. Longevity is a criterion.Longevity is a criterion.

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Defining Healthy Body WeightDefining Healthy Body Weight– Body mass index (BMI) measures Body mass index (BMI) measures

relative weight for height.relative weight for height. Underweight is a BMI below 18.5.Underweight is a BMI below 18.5. Overweight is a BMI above 25.Overweight is a BMI above 25. Obese is a BMI above 30.Obese is a BMI above 30.

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Body Fat and Its DistributionBody Fat and Its Distribution– Fat DistributionFat Distribution

Intra-abdominal fat around abdominal Intra-abdominal fat around abdominal organs may be critical.organs may be critical.

Central obesity is excess fat around the Central obesity is excess fat around the trunk of the body. It is also called abdominal trunk of the body. It is also called abdominal fat or upper-body fat.fat or upper-body fat.

Associated with increased risksAssociated with increased risks

Visceral Abdominal Visceral Abdominal FatFat

Fat mainly around the waist is Fat mainly around the waist is more likely to develop health more likely to develop health problems than fat mainly in hips problems than fat mainly in hips and thighs. and thighs.

This is true even if BMI falls within This is true even if BMI falls within the normal range.the normal range.

WMWaist Management

Waist Waist CircumferenceCircumference

To measure waist circumference, To measure waist circumference, place a tape measure around place a tape measure around bare abdomen just above hip bare abdomen just above hip bone. bone.

Be sure that the tape is snug, but Be sure that the tape is snug, but does not compress your skin, does not compress your skin, and is parallel to the floor. Relax, and is parallel to the floor. Relax, exhale, and measure waist.exhale, and measure waist.

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Body Fat and Its DistributionBody Fat and Its Distribution

– Waist CircumferenceWaist Circumference

Women with a waist Women with a waist measurement of more than measurement of more than 35 35 inchesinches

Men with a waist measurement Men with a waist measurement of more than of more than 40 inches40 inches

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Body Fat and Its DistributionBody Fat and Its Distribution– Measures of Body CompositionMeasures of Body Composition (%BF)(%BF)

Monitoring changes over time is Monitoring changes over time is important.important.

Fatfold measuresFatfold measures HydrodensitometryHydrodensitometry Bioelectrical impedanceBioelectrical impedance

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Health RisksHealth Risks Associated with Body Associated with Body Weight and Body Fat Weight and Body Fat – An appropriate weight for an individual An appropriate weight for an individual

depends on many factors which include body depends on many factors which include body fat distribution, health history and current state fat distribution, health history and current state of health.of health.

– Health Risks of UnderweightHealth Risks of Underweight Cannot handle medical stressesCannot handle medical stresses Menstrual irregularities and infertilityMenstrual irregularities and infertility Pregnancy problemsPregnancy problems Osteoporosis and bone fracturesOsteoporosis and bone fractures

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Health RisksHealth Risks Associated with Associated with Body Weight and Body Weight and Body FatBody Fat

DiabetesDiabetes HypertensionHypertension CardiovasculaCardiovascula

r diseaser disease Sleep apneaSleep apnea OsteoarthritisOsteoarthritis Some cancersSome cancers

Gallbladder Gallbladder diseasedisease

Kidney diseaseKidney disease Respiratory Respiratory

problems – problems – Pickwickian Pickwickian syndromesyndrome

Complications Complications in pregnancy in pregnancy and surgeryand surgery

Body Weight, Body Body Weight, Body Composition, and HealthComposition, and Health

Health Risks Associated with Body Health Risks Associated with Body Weight and Body FatWeight and Body Fat– Cardiovascular disease and obesity have Cardiovascular disease and obesity have

a strong relationship.a strong relationship.– Diabetes and obesity have a strong Diabetes and obesity have a strong

relationship.relationship. Insulin resistance and obesity have a strong Insulin resistance and obesity have a strong

relationship.relationship.

Eating DisordersEating Disorders

Eating DisordersEating Disorders

Many individuals, including young Many individuals, including young females, suffer from eating disorders. females, suffer from eating disorders.

These include anorexia nervosa, These include anorexia nervosa, bulimia nervosa and binge-eating bulimia nervosa and binge-eating disorders. disorders.

The causes include a combination of The causes include a combination of sociocultural, psychological, and sociocultural, psychological, and perhaps neurochemical factors. perhaps neurochemical factors.

Athletes are among the most likely Athletes are among the most likely group to develop eating disorders.group to develop eating disorders.

The Female Athlete TriadThe Female Athlete Triad

Disordered eating habits can Disordered eating habits can develop.develop.– Desire to improve performanceDesire to improve performance– Enhance aesthetic appeal of their Enhance aesthetic appeal of their

performanceperformance– Meet unsuitable weight standardsMeet unsuitable weight standards

The Female Athlete TriadThe Female Athlete Triad

OsteoporosisOsteoporosis– Stress hormones compromise bone Stress hormones compromise bone

health.health.– Stress fractures are common bone Stress fractures are common bone

injuries.injuries.– Adequate calcium is recommended.Adequate calcium is recommended.

Preventing Eating Disorders Preventing Eating Disorders in Athletesin Athletes

Follow USDA Food Guide for food Follow USDA Food Guide for food servings.servings.

Eat frequently, especially healthy Eat frequently, especially healthy snacks.snacks.

Establish a reasonable weight goal.Establish a reasonable weight goal. Allow reasonable time to achieve the Allow reasonable time to achieve the

weight goal.weight goal. Join a weight maintenance support Join a weight maintenance support

group.group.

Anorexia NervosaAnorexia Nervosa

Characteristics of Anorexia NervosaCharacteristics of Anorexia Nervosa– Self-starvation – tremendous self-control Self-starvation – tremendous self-control

to limit eatingto limit eating– Physical consequences are major and Physical consequences are major and

life threatening.life threatening. Treatment is multidisciplinaryTreatment is multidisciplinary

– Food and weightFood and weight– Relationships with self and othersRelationships with self and others

Bulimia NervosaBulimia Nervosa

Characteristics of Bulimia NervosaCharacteristics of Bulimia Nervosa– Binge eating – lack of control over eating, Binge eating – lack of control over eating,

excessive kcalories from high-fat, low-fiber and excessive kcalories from high-fat, low-fiber and high-carbohydrate foods eaten all at oncehigh-carbohydrate foods eaten all at once

– Purging – cathartic and/or emetic Purging – cathartic and/or emetic Treatment of Bulimia Nervosa Treatment of Bulimia Nervosa

– Weight maintenanceWeight maintenance– Regular exerciseRegular exercise– CounselingCounseling

Fig. H8-2, p. 275

Negative self-perceptions

Purging Restrictive dieting

Binge eating Stepped Art

Binge-Eating DisorderBinge-Eating Disorder An unspecified eating disorder sharing some of An unspecified eating disorder sharing some of

the characteristics of anorexia nervosa and the characteristics of anorexia nervosa and bulimia nervosa yet does not meet the criteria bulimia nervosa yet does not meet the criteria for diagnosis. for diagnosis.

Lack of self-control over eating with bingesLack of self-control over eating with binges Consuming large quantities of food, eating Consuming large quantities of food, eating

quickly, feeling uncomfortably full, eating quickly, feeling uncomfortably full, eating alone, and feeling disgusted or guiltyalone, and feeling disgusted or guilty

Marked distressMarked distress Occurrence of two times per week for six Occurrence of two times per week for six

monthsmonths Not associated with compensatory behaviorsNot associated with compensatory behaviors

Eating Disorders in SocietyEating Disorders in Society

Occur more commonly in developed Occur more commonly in developed nations where food and money are nations where food and money are plentiful plentiful

Learning to appreciate the Learning to appreciate the uniqueness of oneself may be a key uniqueness of oneself may be a key to prevention.to prevention.