Body Composition
and
Weight Management
Unit 5: Body Composition and Weight Management
OBJECTIVES FOR THIS UNIT:
Students will:
• 1) Understand the various components of body
composition.
2) Discuss how percent body fat is related to overall
health.
3) Describe healthy and unhealthy levels of body fat in
high school students.
4) Describe some methods of assessing body fatness, and
discuss some "pro’s" and "con’s" of each method.
5) Understand some health hazards of being overweight,
and be introduced to eating disorders.
Assignment List
(Optional) Textbook Reading For Unit 5:
Chapter 13 (pages 220-241)
At the end of this lesson you will have completed the following assignments:
05.02 – Activity Log 7
05.2.1 – Exercising with Weight Added
05.3.1 - Determining Your Healthy Body Weight
05.4.1 Unit 5 quiz
05.4.2 Activity Log 8
Obesity Trends Among U.S.
Adults between 1985 and 2009
• Obesity is having a very high amount of
body fat in relation to lean body mass, or
Body Mass Index (BMI) of 30 or higher.
• Body Mass Index (BMI) is a measure of an
adult’s weight in relation to his or her height,
specifically the adult’s weight in kilograms
divided by the square of his or her height in
meters.
Obesity Trends Among U.S.
Adults between 1985 and
2009
• The data shown in these maps were collected
through CDC’s Behavioral Risk Factor Surveillance
System (BRFSS). Each year, state health
departments use standard procedures to collect
data through a series of monthly telephone
interviews with U.S. adults.
• Prevalence estimates generated for the maps
may vary slightly from those generated for the
states by BRFSS (http://aps.nccd.cdc.gov/brfss)
as slightly different analytic methods are used.
US Body Composition Rates
• The below slides indicate the rise of obesity within the
United States from 1985 to 2009. Each US state indicates
a BMI level of 30 or greater, or individuals who are at
least 30 lbs. overweight in that particular state. BMI
levels range from:
• (0-No Data to greater than 30%) in certain states.
• Obesity is having a BMI of 30 or higher.
The following map images are from the CDC, public domain
Obesity Trends* Among U.S. Adults
BRFSS, 1985
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
Obesity Trends* Among U.S. Adults
BRFSS, 1991
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
15%–19%
Obesity Trends* Among U.S. Adults
BRFSS, 1997
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
15%–19%
≥20%
Obesity Trends* Among U.S. Adults
BRFSS, 2000
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
15%–19%
≥20%
Obesity Trends* Among U.S. Adults
BRFSS, 2003
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
15%–19%
20%–24%
≥25%
Obesity Trends* Among U.S. Adults
BRFSS, 2006
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
15%–19%
20%–24%
25%–29%
≥30%
Obesity Trends* Among U.S. Adults
BRFSS, 2009
(*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person)
No Data
<10%
10%–14%
15%–19%
20%–24%
25%–29%
≥30%
Obesity Trends* Among U.S. Adults
BRFSS, 1990, 1999, 2009
(*BMI  30, or about 30 lbs. overweight for 5’4” person)
1999
1990
2009
No Data
<10%
10%–14%
15%–19%
20%–24%
25%–29%
≥30%
Statistics:
America:
60.1 % of adults are overweight or obese
23.4% are obese
In Utah:
58.4% of adults are overweight or obese
21% percent are obese
103% increase nationally in past 14 years
112% increase in Utah in past 14 years
Excess Body Weight and Reduction
of Lifespan
Years of
diminished
lifespan
[ie, a person with a
BMI of 34 is likely to
live five years less
than a person with a
BMI of 25]
Body Mass Index
Image from Wikimedia Commons: Peter Forster, Creative Commons Attribution 3.0 Unported license
Obesity and Diabetes:
• Using the most accurate data available, it is estimated
that 36% of all children born in the year 2000 will become
diabetic sometime in their lives; among Hispanics, 50%
will become diabetic.
mage from Wikimedia Commons, Robert Lawton, Creative Commons Attribution-Share Alike 2.5 Generic
Estimated lifetime risk of developing diabetes for
individuals born in the United States in 2000
60
Percent
50
Total
Non-Hispanic Black
Non-Hispanic White
Hispanic
40
30
20
10
0
Men
Narayan et al, JAMA, 2003
Women
Image from CDC, public domain
Diabetes and Reduction in Lifespan
-14.3 yrs
-11.6 yrs
JAMA 2003;290:1884-1890
Body Composition &
Weight Management
• Body Composition is the makeup of body tissues,
including muscle, bone, body fat, and all other
body tissues.
• Lean Body Mass is muscle tissue and other nonfat tissue such as bones, skin, body organs,
ligaments and tendons. This is normally about 7585% of our weight.
• Fat Mass is the amount of fat in our body. This is
normally about 15-25% of our weight.
The Term: Obesity
• Obesity is the condition of being very over-fat or having a high
percentage of body fat (Approx. 35% for women, 30% for
men.)
What should my body fat be?
• For men, essential body fat makes up about 3% of total
body weight. For women, the percentage is higher about 12% - because it includes amounts in the breasts,
pelvis, hips and thighs believed necessary for normal
female reproductive function.
• Men should have a body fat of 10-20% to be in a healthy
range. Men can have less than 10% and still be healthy.
• Women should have a body fat percentage of 15-25%.
Girls who are below this range may begin to have health
issues and may stop menstruation.
Ideal Body Weight:
• Ideal body weight is how much you
should weigh if you had an
appropriate amount of body fat.
ner image from Ookaboo, Wikimedia Commons, Lepax, Creative Commons Attribution-Share Alike 2.0 Generic;
Parade image from Wikimedia Commons, NARA, public domain
Body Fat in Women
• Women tend to have more body fat than
men—about 5% more. By nature, a
woman's body is developed to protect her
and a potential fetus. As a result, women
have more enzymes for storing fat and
fewer enzymes for burning fat.
Additionally, the estrogen women have
activates fat-storing enzymes and causes
them to multiply.
• The minimum percent body fat considered
safe for good health is 12-14% for females.
The average adult body fat is closer to
22%-25% for women.
mage from Wikimedia Commons, Renoir, public domain
Factors that Influence Body Fatness:
•
•
•
•
•
Heredity
Metabolism
Diet/High sugar intake
Lack of physical activity
Early fatness – Last month of fetal development, or 1st
year of life.
• TV / Lifestyle-About 38.2 percent of Utah public high
school students watch three or more hours of television
per day on an average school day.
How do I Find my Body Fat Percentage?
There are several methods one can use to determine
body fat percentage:
1.Underwater/Hydrostatic Weighing
2.BOD POD
3.Electrical Impedance
4.Skin Calipers
5.Girth Measure/Body Circumference
6.Waist to Hip Ratio
7.Body Fat Scale
8.BMI
Underwater/Hydrostatic Weighing
• Underwater weight is the best and most
accurate measurement for body fat.
• Advantages: Underwater weighing is the
most widely used test of body density and
in the past was the criterion measure for
other indirect measures.
• Disadvantages: The equipment required
to do underwater weighing is expensive.
The tanks are mostly located at university
or other research institutions, and there is
generally not easy access for the general
population.
The BOD POD
• The BOD POD Body Composition
Tracking System uses patented Air
Displacement Plethysmography for
determining percent fat and fat-free
mass in adults and children. The
simple, five-minute test consists of
measuring the subject's mass
(weight) using a very accurate
electronic scale, and volume, which
is determined by sitting inside the
BOD POD chamber. From these two
measurements, the subject's body
composition is calculated.
Electrical Impedance
What is the Bioelectrical Impedance Method?
Muscles, blood vessels and bones are body
tissues having a high water content that conduct electricity easily.
Body fat is tissue that has little electric conductivity. The Analyzer
sends an extremely weak electrical current of 50 kHz and 500µA
through your body to determine the amount of fat tissue. This
weak electrical current is not felt while operating the Body Fat
Analyzer. The Bioelectrical Impedance Method safely combines the
electric resistance with the distance of the electricity conducted.
Skin Calipers
• Calipers work by pulling subcutaneous fat (fat directly
under the skin) away from the muscle with the tongs
situated at their ends. Several predetermined sites
are measured by a gauge that records the thickness
of the pinch created by the tongs. An equation can be
used to determine body-fat percentage, or the skinfold thicknesses, on their own, can be used to gauge
progress.
• Men – Chest, Abdomen, Thigh
• Women – Triceps, Waist, Thigh
Girth and Body Circumference
• Girth measurements are circumference
measurements taken at a specific body site
and recorded. They are converted to a
constant and then entered into a formula
to predict percent body fat. The sites
measured differ depending on a person's
age and gender.
• For ages 18 to 26: Men measure the right
biceps, right forearm, and abdomen.
• Women measure the abdomen, right thigh
and right forearm.
Image from Wikimedia Commons, Ron Mahon, Creative Commons Attribution 3.0 Unported
Waist Circumference
• Measuring waist circumference
helps screen for possible health
risks that come with overweight
and obesity. If most of your fat
is around your waist rather than
at your hips, you’re at a higher
risk for heart disease and type 2
diabetes. This risk goes up with
a waist size that is greater than
35 inches for women or greater
than 40 inches for men.
Image from Wikimedia Commons, Aspen04, Public domain
Waist to Hip Ratio
• Waist to Hip Ratio is one way to
determine your health risk. In
addition to measuring your waist,
measure your hips at the widest part.
Divide your waist measurement by
your hip measurement.
• For women a ratio of 0.80 is safe.
• For men a ratio of 0.90 is safe.
• For both men and women, a 1.0 or
higher is considered “at risk”, or in the
danger zone for undesirable health
consequences, such as heart disease.
Body Fat Scale
• Professional body fat monitors measure weight, body fat
percentage, hydration level, lean body mass, BMI (body
mass index) and more. A convenient printer, available with
most professional body composition analyzers, makes it
simple to update patient or client records with current data.
BMI – Body Mass Index
• Obesity and overweight are commonly defined in terms of
the body mass index (BMI). **BMI is calculated using a
person’s height and weight.
**BMI = weight (lbs) x 703/height squared (in2)
(In Adults)
• BMI of 18.5 to 24.9 is considered to be ideal, and anything
above this is defined as overweight. A BMI greater than or
equal to 30 is defined as obese.
• Visit the website below to calculate your BMI:
• http://www.nhlbisupport.com/bmi/
Health Hazards and Obesity
•
•
•
•
•
•
•
•
Breathing Difficulties
Diabetes
Cancer (many types)
High Blood Pressure
Heart Disease/Stroke
Kidney Disorders
Shorter Life Span
Pregnancy Problems in
women
•
•
•
•
•
•
•
•
Arthritis
Hypertension
High Cholesterol
Sleep Apnea
Respiratory Problems
Surgical Risk
Prone to infections
Social Discrimination
Healthy Weight Loss
• One should try to lose weight by
doing it in a healthy way.
Exercise and a healthy diet are
the best way to reduce body fat.
• Include a weight training
program to help stimulate the
metabolism.
Can you lose fat in just
one area?
• There is no such thing as spot
reduction. You can’t just lose fat on
your hips, back, or stomach. As you
exercise and eat right, fat will decrease all
over your body, not just in one particular
spot.
Fad Diets and Weight Loss
Gimmicks Don’t Work!!!
• The world has an unhealthy obsession with 'fad' diets. This is due
to the American culture's need for a magic bullet or solution that
provides immediate gratification. Technically, a diet simply refers
to what you eat each day. In the truest sense, we are all on a diet
daily - the question is, is it healthy or not?
• Another drawback of fad diets is that many of them don't work at
all. Some, such as those based on diuretic herbs, simply cause a
loss of water rather than fat. This water is simply regained back
by the body and is then retained with a vengeance after you are
off the diet. This is known as rebound weight gain.
• Diets fail because they offer no long-term solution.
http://www.healthstatus.com/articles/Weight_Loss_Fads_that_Don_t_Work.html
Image: SusanLesch,
CC Attribution-Share
Alike 3.0 Unported
Set Goals, Eat Healthy and Exercise
• No matter what the reason, successful weight loss and
healthy weight management depend on sensible goals and
expectations. If you set realistic goals for yourself, chances
are you'll be more likely to meet them and have a better
chance of keeping the weight off. In fact, losing even 5 to 10
percent of your weight is the kind of goal that can help
improve your health.
Most overweight people should lose weight gradually. For safe
and healthy weight loss, try not to exceed a rate of
2 pounds per week. Sometimes, people with serious health
problems associated with obesity may have legitimate
reasons for losing weight rapidly.
Key Vocabulary
• Bioelectric Impedence Analysis (BIA) is a technique based upon the principle that
electrical currents travel faster through water. Therefore, if a person receives a
small electrical current in their arms or legs (cylinder-shaped areas of the body),
individuals with more muscle will have faster conductance (or current travel) rates.
• Bod Pod is a very new device that uses air displacement to estimate percent body
fat.
Body Composition is defined as the various fat and nonfat components of your
body.
Body Mass Index is known as BMI and examines weight in proportion to height in
an index (kg/m 2 ).
• Fat Mass is adipose tissue (fat)
• Girth Measurements are techniques whereby you measure the width or girth of
various body parts (e.g., upper arm, hip, waist, and wrist) and plug the
circumferences into a formula, and your body composition is estimated.
• Ideal Body Weight means how much you would weigh if you had an appropriate
percent of body fat.
Key Vocabulary Continued
•
Lean Body Mass consists of parts of the body such as connective tissue, muscle, bone, and
organs.
• Obesity is a condition in which a person has high percentage of body fat.
• Overweight - People considered to be overweight exceed their desirable bodyweight by 10%
according to height and weight charts.
Skinfold Calipers are used to measure skinfolds at various sites; because at least 1/2 of the
body's tissues are subcutaneous, we can assume that a certain width of skinfold tissue
equates to an overall percent body fat value.
•
Underwater or Hydrostatic Weighing is the “gold standard” by which all other techniques
are compared, is a technique that requires subjects to exhale as forcefully as possible to
minimize air bubbles, and then submerge themselves on an underwater scale.
Waist Circumference is a more current technique where by the circumference of the waist,
at the widest point from the side view, is used to estimate health risk.
• Waist-to-Hip Ratio is a ratio obtained by dividing the circumference of the waist (at the
umbilicus) by the circumference of the hips (at the widest point from the side view).