4.7.08 Fat loss/ Behavior Modification

Isocaloric /energy balance:
When caloric intake=caloric expenditure

Positive energy balance:
When caloric intake is greater than caloric expenditure.
3500 kcals = 1 lb. of fat
Leads to weight gain

Negative energy balance
When caloric intake is less than caloric expenditure
Leads to weight lostt

Assess body composition before starting a weight loss program

Identify ideal body weight
IDEAL BW= Present FFM (lbs.)/ Goal FFM (%)

Example male:
42 years old
223 lbs.
5'11"
% BF=30% (70% FFM)
Goal is 15% (85% FFM)

Ideal BW= 156.1 lb./ .85 = 183.65 lbs.
must lose 40 lbs. of fat mass

Identify what their diet is like.

RMR=Resting metabolic rate
REE=Resting energy expenditure
BMR=different, but for our purposes, they are the same.

The minimum amount of kcals required to sustain the vital functions of the body
Accounts for 50-70% of total daily caloric expenditure
For sedentary ppl (70%)
For active ppl (50%)
Harris-Benedict equations (given on the test)

DIT=Dietary induced thermogenesis
Involves the caloric requirements of digestion and absorption
Accounts for ~10% of total energy consumed from meals
Included in RMR
AKA TEF (Thermal effect of food)

Eat a lot of small meals frequently to increase DIT

Caloric requirements of their job.
(PDL) Based on 8 hr. work week 5 days per week (40 hr. work week)

Fat Loss Program:

Negative Caloric Balance
Aerobic Exercise
Behavior Modification

1 lbs. per week= 3500 kcals
3500/7 = 500
will take 40 weeks for example male to lose his 40 lbs.

2 lbs. per week= 7000
1000 kcals per day expenditure

kcals/min= [(METs)(3.5)(BWkg)]/200

Aerobic exercise-karvonen formula

Behavior Modification:
Technique used to elicit a desirable behavior that will last

May involve learning new behaviors or unlearning/modifying old behaviors

Cue/stimulus ---> behavior----> consequenses

The behavior of overeating which leads to getting fat (consequence) is due to some cue or stimulus.

So is the behavior of inactivity

The goal of behavior modification in terms of fat loss are:
1. to eliminate the stimulus
2. engage in more appropriate behaviors
3. emphasize the consequences- 87% of people of people who lose weight via low kcal, quick wt. loss program will gain wt. back and more within 2 years.

What is the cue or stimulus?

time
environment
feelings
people/social
tv
car, etc.
buffett
holidays
vacations
cost
vending machines
eat what's left on child's plate

Behavior?

instead of eating...
drink water
walk
have breakfast
make all foods yourself
keep busy
no on eats at the tv
not while reading
spousal help

Focus on Consequences:
fat pictures up around the house
bikini sitting out in site

Weight Gain Programs
Muscle gain
very difficult to do
very little research

3 reasons
performance
appearance
health

author suggests: 5-10

3.31.08 Body Composition

Describes the makeup of the human body into 2 components: FM and FFM.

FM
Must have a certain amount of fat on the body-essential fat: for the brain, mylin sheath, cells, etc. And stored fat.

FFM
Protein/muscle (21%)

Water (72%)
Mineral (7%)

The nutrient and health status of an individual can be estimated by the individual's body composition.

Obesity

1. A body wt. that exceeds by more than 20% the desirable level for a given age, gender, and skeletal frame. (NIH, 1985).

2. Overfat: An excess of body fat at which health risks begin to increase (HHS, 1988).
No #s associated with this definition.

3. Males > or = 25%
Females > or = 32%

Overweight

Body wt. above some standard of acceptable weight (10-20%) that is usually defined by relations to height, age, gender, and skeletal frame.

Obesity and Health Risks

1. Inc. risk of CVD (Heart disease and stroke)
2. Inc. risk of HBP (2.9 X more likely)
3. Inc. risk for High blood cholesterol (2.1 X)
4. Inc. risk of Type II diabetes (2.9 X)
5. Inc. risk of obstructive pulmonary disease (COPD, asthma, etc.)
6. Inc. risk of osteoarthritis in weight bearing and non-weight bearing parts.
7. Inc. risk of certain cancers.

Types of Obesity

1. Hyperplastic: creating additional fat cells.
2. Hypertrophic: existing fat cells get bigger.

1 function of a fat cell-store more fat/get bigger.

5 pts. that we see #1.

Infancy 0-1 year (F&M)
Puberty (F&M)
Pregnancy (F)
Menopause (F)
Morbid obesity (>70%) (F&M)
*Genetic potential of a fat cell to hold a certain amount of fat
*Cells split off and then get bigger.

Only lose fat by cells getting smaller-you keep the same # of fat cells.


Methods of Body Fatness &/or Health Risks

1. Weight-for-height tables
* Metropolitan Life Insurance Co. Tables
* 1959; revised 1983
*based on gender, height, weight, and skeletal frame size.
*frame size via
a. elbow breadth
b. ht.-wrist circumference ratio

r= height (cm)/ wrist cir. (cm)

ht. inches x 2.54

See Met Life table

Actual weight/upper # on your range = % you are over

<10% is normal risk

2. Body Mass Index:
(NOT % BF!!)

BMI: Weight (kg)/(height m)^2

Associated health risk:

BMI Vs. Health risk
<18.5% / Malnutrition, serious disease
18.5-24.9 / Healthy
25-30 / Overweight
>30 / Obese
>35-40 / Morbid Obesity

*Inc. risk for CVD
if:
Males: > or = 25
Females: > or = 25

Not accurate w/athletes
- muscle mass
-but for average American it is a good indicator of health

3. Waist to Hip Ratio (WHR)
Identify whether you tend to carry fat androidally or gynoidally

a. android
*male pattern
*apple
*abdominal fat
*assoc. with diabetes, CVD, HBP

b. gynoid
*female pattern
*pear shape
*hip, buttock, thigh fat
*No additional risk associated that android does
*very stable fat stores

Waist measured @ smallest circumferance
hip measured @ greatest circ. including buttocks
WHR: Waist/hip
*Inc. risk
Males: > or = .86
Females: > or = .95

4. Hydrostatic/Underwater weighing
*"Gold Standard" of BC

Assumed: Density of FFM= 1.1g/ml (not true)
Density of FM= .901g/ml (true)
Density of Water= 1 g/ml (true except in temperature changes)
Standard error= +/- 2-2.5%

5.BIA (Bioelectrical Impedence Analysis)
*Introduces electrical current through body from hand to foot, foot to foot, or hand to hand.

Muscle= 70% water (faster current, electrolyte full)
Adipose = 10% water (slower current, electrolyte empty)

Can estimate % BF based on speed of conduction
*Standard error = +/- 3-4% only if you adhere to the following:

No food or drink (including water) within 4 hours
No mod or vig exercise within 12 hours
No alcohol within 48 hours
No diuretics/caffine prior

6. Skinfold Measurements (SKF)
Estimates subcutaneous fat to extrapolate visceral stores
33% subcu
67% visceral
SKF formulas are specific to gender, ethnicity, and age
*Standard error = +/- 3%

Contraindications: Bloated female, pregnant female, after aggressive exercise.

7. Near infrared Reactance (NIR)
Introduce NI light to different body sites.

This light is absorbed differently depending on chemical composition (muscle vs. fat) can estimate % BF

All 9 sites used
*bicept was found to be most representative for both males and females
*correction factor for skin color (color wheel to match to bicept color)
*Standard error of >5%
Pg. 68 pkt. Body comp norms - KNOW THESE!!

Prevalence of Obesity:

35% of female adults
31% of male adults

~60% of US adults >25% BMI
33.4% of US adults are >20% ideal wt. (obese)

1962= 24.4%

Classified as Obese:
Anglo women: 32%
Hispanic: 47%
Black: 49%
This phenomenon is not seen in males

Causes of Obesity:

1. Genetics- 80% chance of being obese if both parents are (even in adopted children)
40% chance if one is obese
<10% chance if neither are

2. Energy Imbalance

Isocaloric diet
then + 100kcals of extra fat
97% will be stored as fat
3 used to convert dietary fat to adipose

+ 100kcals of extra CHO
74% stored as fat
26% used to convert dietary to adipose

+ 100kcals of extra Protein
24% used for digestion and absorption
? used to convert dietary protein into adipose
Rest stored