Body Weight Management

Chapter 8Chapter 8

Managing Your Weight:Finding a Healthy Balance

WEIGHT CONTROL AND HEALTH

Health risks associated withHealth risks associated withexcess adipose tissue andexcess adipose tissue andinactivity:inactivity:

• heart diseaseheart disease

• diabetesdiabetes• hypertensionhypertension• cancercancer• osteoarthritisosteoarthritis

Also question of self-conceptAlso question of self-conceptand emotional health.and emotional health.

BODY COMPOSITION

Total body mass is Total body mass is composed of 2 composed of 2 components:components:

• fat mass (FM)fat mass (FM)

• fat-free mass (FFM) fat-free mass (FFM) (composed of muscles, (composed of muscles, bone, water, and bone, water, and viscera)viscera)

Body composition is influenced byBody composition is influenced by

• genetic factorsgenetic factors

• environmental factorsenvironmental factors

• nutritionnutrition

• diseasedisease

• physical activityphysical activity

BODY FAT MASS

• energyenergy

• storage / vitaminsstorage / vitamins

• protects internal organs protects internal organs

• insulates body against insulates body against extreme cold extreme cold

Essential Fat• essential fat required essential fat required

for normal function of for normal function of CNS CNS

• stored in muscles, stored in muscles, heart, lungs, liver, heart, lungs, liver, spleen, intestines, spleen, intestines, kidneys + bone kidneys + bone marrowmarrow

• men is 3%men is 3%

• women is 12%women is 12%

Storage Fat (subcutaneous fat)

• storage fat is deposited in storage fat is deposited in adipose tissue - energyadipose tissue - energy

• # of fat cells remains # of fat cells remains constant - size reducedconstant - size reduced

• location of storage fat location of storage fat variesvaries

• protects internal organsprotects internal organs

General Rating of Body Fat % by Age and Sex

Rating Males

(ages 18-30) %

Females

(ages18-30) %

Essential 3 12

Athletic 6-10 10-15

Good 11-14 16-19

Acceptable 15-17 20-24

Overfat 18-19 25-29

Obese 20+ 30+

HEALTH RISKSHEALTH RISKS

Underweight Underweight

• nutritional nutritional deficienciesdeficiencies

• anemiaanemia• heart disease/defectsheart disease/defects• chronic fatiguechronic fatigue• infectioninfection• depressiondepression

OverweightOverweight

• hypertensionhypertension• diabetesdiabetes• heart diseaseheart disease• orthopedic problemsorthopedic problems• respiratory problemsrespiratory problems

Body Fat Distribution

• gender differences gender differences

• approx. 9-yr. boys deposit approx. 9-yr. boys deposit fat - abdomenfat - abdomen

• approx. 9-yr. girls deposit approx. 9-yr. girls deposit fat - hips and legsfat - hips and legs

• differences accentuate with differences accentuate with puberty and maturationpuberty and maturation

Body Fat Distribution

• men - android pattern - men - android pattern - apple-shaped (fat stored apple-shaped (fat stored in trunk, chest, back, and in trunk, chest, back, and abdomen)abdomen)

• women - gynoid pattern - women - gynoid pattern - pear-shaped (fat stored pear-shaped (fat stored in hips and legs)in hips and legs)

FAT-FREE MASS (FFM)

• muscle, skin, bone, and viscera

• midlife FFM declines/men and women/decrease in muscle mass

• FFM decreases 3 kg per decade/1.5 times greater in men than women

• decrease of FFM/decrease in growth hormone with aging

• physical inactivity

OVERWEIGHT OR OVER-FAT?OVERWEIGHT OR OVER-FAT?WAYS TO MEASURE BODY FAT AND BODY

COMPOSITION

• Body Weight vs.Body Weight vs.

Body CompositionBody Composition• Scales = Body Weight OnlyScales = Body Weight Only

• Body Mass Index (BMI) =mass (kg)stature (m2)

• Men > 27,8 = overweight• Women >27,3 = overweight• BMI >30 = obese

WAIST TO HIP RATIO

• correlation between fat stored in mid-section and disease

• divide waist measure by hip measure

• if above 0.8 for females and >0.95 for males people risk for heart disease, high blood pressure and diabetes.

SKINFOLDS

• measure of subcutaneous fat

• fifty percent of body fat beneath skin - therefore percentage body fat can be calculated from skinfolds measures

• subject to error

RESEARCH SETTINGS AND BODY FAT EVALUATION

• total body electrical conductivity (TOBEC)] - electromagnetic force field

• bio-electrical impedance (BIA) - pass current through body

• soft-Tissue Roentgenogram - inject radioactive substance into lean body mass……. Muscle - Fat Mass ID

Hydrostatic Weighing Techniques

• Determines fat mass Determines fat mass by submerging the by submerging the body in water- body in water- displaced water is displaced water is measuredmeasured

• densities of lean and densities of lean and fat mass are knownfat mass are known

• compares out-of-compares out-of-water and under-water and under-water weightwater weight

CAUSES OF OBESITY

Heredity

• Twins research: different family Environments - Same Genetic Make – Up

• 1 parent obese = 55% - children tendency to being overweight or obese

• 2 parents obese = 90% - children tendency to being overweight or obese

Heredity Continued….

• neither parent obese = 15% chance children will tend to be overweight or obese

• genes set metabolic rates

• nutritional choices + exercise can modify the genetic effect

Exercise / LifestyleExercise / Lifestyle

• Increases metabolic Increases metabolic rate- up to severrate- up to several hours hours after exerciseafter exercise

• F.I.T.T. principlesF.I.T.T. principles

• energy from stored energy from stored Fat/CHO/ProteinFat/CHO/Protein

• critical component – critical component – reset the Set Pointreset the Set Point

• one pound of body fat one pound of body fat contains 3500 caloriescontains 3500 calories

Errant Eating & Thrifty Genes

Errant Eating:Errant Eating:• ““I’ve had enough to I’ve had enough to

eat” - defective geneeat” - defective gene

Thrifty Genes:Thrifty Genes:• survival mechanism survival mechanism

when food isn’t when food isn’t available…..available…..

• lower metabolic ratelower metabolic rate

Metabolic RatesMetabolic Rates

• BASAL METABOLIC RATE - lean muscle mass vs. fat mass

• RESTING METABOLIC RATE = BMR + other sedentary activities ( 90%) of Energy

• EXERCISE METABOLIC RATE = RMR (90%) + Moderate to Heavy Activity (10%)

• Opportunity for Weight Loss

Fat Cell Theory

Approximate Number of Approximate Number of Fat Cells (ADULTFat Cells (ADULT)

• Average Weight – 25 to Average Weight – 25 to 30 Billion30 Billion

• Moderately Overweight – Moderately Overweight – 60 to 100 Billion60 to 100 Billion

• Obese –Obese – 200 Billion200 Billion

Fat Cell SizeFat Cell Size

• Hypertrophy (SIZE)Hypertrophy (SIZE)Adults and childrenAdults and children

• Hyperplasia (NUMBER) Hyperplasia (NUMBER)

Last-Trimester Pregnancy Last-Trimester Pregnancy (Mother’s Dietary Habits)(Mother’s Dietary Habits)

• 11stst Year of Life Year of Life

• 9 to 13yr.9 to 13yr.

• extremely obese peopleextremely obese people

Set Point Theory

• internal control mechanism for body to maintain certain weight

• research into dieting - lowers

the metabolism - dieting

ineffective (95%) - need

lifestyle changes as well

• also work done with overfeeding -similar shift but in opposite direction

Psychosocial Factors:

• Emotional insecurities, Emotional insecurities, childhood rewards, childhood rewards, unemployment, broken unemployment, broken relationships, financial relationships, financial uncertainty, etc, etc…uncertainty, etc, etc…

• A Bright Spot … FOOD…!A Bright Spot … FOOD…!

• Eating is a social ritual – Eating is a social ritual – companionship, celebration, companionship, celebration, enjoyment….an event!enjoyment….an event!

Eating Habits:

• Learned and Learned and perpetuated by perpetuated by family? family?

• Situation? Situation?

• Money? Money?

• Break the Cycle – Break the Cycle – Food & Eating Food & Eating AnalysisAnalysis

SUCCESSFUL WEIGHT SUCCESSFUL WEIGHT

MANAGEMENTMANAGEMENT Role Of Diet /Nutrition:Role Of Diet /Nutrition:

• balanced nutrition vs. a balanced nutrition vs. a ”diet"”diet"

• initial losses mostly waterinitial losses mostly water

• impairs physical functionimpairs physical function

• lowers basal metabolic ratelowers basal metabolic rate

• repeat dieting leads to repeat dieting leads to greater fat levelsgreater fat levels

• severe restrictions altersevere restrictions alter the optimal balance ofthe optimal balance of

nutrient intakenutrient intake

Weight LossWeight Loss

Set Goals

• improve quality improve quality of life through of life through lifelong weight lifelong weight managementmanagement

• weight loss weight loss approximately 1 approximately 1 lb. / weeklb. / week

Changing Attitudes

• examine reasons for eating - examine reasons for eating - track behaviors that trigger track behaviors that trigger eatingeating

• Keep track of what you eat, Keep track of what you eat, when, and why!when, and why!

• Hypothalamus senses hunger Hypothalamus senses hunger while the while the

• SATIETY CENTRE sends SATIETY CENTRE sends indication of fullness. indication of fullness.

Changing Attitudes

• A 20 minute delay occurs A 20 minute delay occurs for satiety to be felt for satiety to be felt

• water / fruit before eatingwater / fruit before eating

• behavior modification is behavior modification is essential to any successful essential to any successful weight management weight management programprogram

ROLE OF EXERCISE

• Very important moderate - Very important moderate - will suppress appetitewill suppress appetite

• lean muscle development lean muscle development results in greater results in greater "burning" of calories"burning" of calories

• basal metabolic ratebasal metabolic rate

• resting metabolic rateresting metabolic rate

• exercise metabolic rateexercise metabolic rate

DANGERS OF QUICK-FIXESDANGERS OF QUICK-FIXESbehaviours aren’t changedbehaviours aren’t changed

• gastric balloon insertiongastric balloon insertion

• stomach staplingstomach stapling

• jaw wiringjaw wiring

• liposuctionliposuction

• new behaviors are not new behaviors are not learnedlearned

• always dangerous i.e. always dangerous i.e. health and life!health and life!

DISORDERED EATING & Eating Disorders

ANOREXIA NERVOSA:

• a morbid fear of being fat

• relentless pursuit of thinness

• condition in which a very thin body is seen as normal

• distorted body image

• suppression of appetite rather than loss of appetite

ANOREXIA NERVOSA

• self-induced starvation or dieting gone out of control

• starvation and over exercise are common

• many social classes and ethnic groups

• often well educated,achievement oriented

ANOREXIA NERVOSA:

• results in death in 5 to 18% of cases (suicide or medical complication)

• decrease in food intake

• increase in purging ( self-induced vomiting)

• misuse of laxatives or diuretics

• dangerous exercise habits

• affects bones, muscles, organs, immune system, nervous and digestive system

ANOREXIA NERVOSA:

– tooth decay – vomit

– (stomach acids) dissolves enamel

– hair loss & development of fine hair on face and body

Treatment

• multifaceted medical and psychological

• drug therapy and behavior modification used

• prognosis often poor

BULIMIA NERVOSAFEELING A LACK OF CONTROLFEELING A LACK OF CONTROL

• uncontrolled binge uncontrolled binge eating followed by eating followed by vomiting /purging the vomiting /purging the body of foodbody of food

• purging through use of purging through use of vomiting, laxatives, vomiting, laxatives, diuretics, exercisediuretics, exercise

• 95% are female95% are female

BULIMIA NERVOSA• also a technique used by

anorexics

• similar risk profile as anorexic - though loss of self-control a factor

• used by athletes to lose weight fast

• treatment complicated

• multidisciplinary approach most effective

UNDERWEIGHT

• regular mealsregular meals

• increase caloric increase caloric intake, intake, particularly particularly complex CHOcomplex CHO

• regular physical regular physical activity - relate activity - relate to self-esteemto self-esteem

AMERICAN COLLEGE OF SPORTS MEDICINE GUIDELINES FOR

WEIGHT CONTROL

• AVOID PROLONGED AVOID PROLONGED FASTINGFASTING

• MILD CALORIC MILD CALORIC RESTRICTION - MAX RESTRICTION - MAX RESTRICTION OF 500-RESTRICTION OF 500-1000/day1000/day

• EXERCISEEXERCISE

• MAINTAIN NUTRITIONMAINTAIN NUTRITION

• BEHAVIOR BEHAVIOR MODIFICATIONMODIFICATION

Hunger, Appetite, SatietyHunger, Appetite, Satiety

• Hypothalamus Hypothalamus Regulates AppetiteRegulates Appetite

• Monitors Levels of Monitors Levels of Nutrients in BloodNutrients in Blood

• Obese eating cues: Obese eating cues: Frequency and Frequency and Intensity increase!Intensity increase!

Adaptive Thermogenesis

• Large Amounts of Large Amounts of foodfood

• No Weight GainNo Weight Gain

• Metabolic Activity Metabolic Activity Adjusts Adjusts

• Brown Fat Cells Brown Fat Cells control the control the thermogenesis thermogenesis responseresponse

Satiety

• Feeling of FullFeeling of Full

• Nutritional NeedsNutritional Needs

• Obese vs. Non-ObeseObese vs. Non-Obese

Why We Eat…….Why We Eat…….

Hunger Hunger

• InbornInborn• PhysiologicalPhysiological• NeedNeed

AppetiteAppetite

• Learned ResponseLearned Response• Emotional//PsychologicalEmotional//Psychological• CravingCraving