Transcript Body Composition - Mrs. Miller's Site

Body Composition
Chapter 6
Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
The Spectrum of Body Size,
Shape and Composition
We All Change in Many Ways
What Is Body Composition?
Body composition = the body’s
relative amounts of fat mass and
fat-free mass (bone, water, muscle,
connective and organ tissues, teeth)
 Essential fat = crucial for normal
body functioning

3–5% of total body weight in males
 8–12% of total body weight in females
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
Nonessential fat = adipose tissue
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Typical Body Composition
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Genetics and Body Composition
People come in all sorts of shapes and sizes. Body
type or physique can greatly affect performance in
different activities.
Body type is also known as somatotype.
A performer’s somatotype can be measured against the
three extreme somatotypes:
Endomorph
Mesomorph
Ectomorph
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Somatotypes
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Endomorph
Extreme endomorphs have the following characteristics:
A lot of body fat
A lot of fat on the
upper arms and
thighs
Wide hips and
narrow shoulders
Fairly slim wrists
and ankles
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Mesomorph
Extreme mesomorphs have the following characteristics:
Very little body fat
A muscular body
Broad shoulders
and narrow hips
A large head
Strong forearms
and thighs
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Ectomorph
Extreme ectomorphs have the following characteristics:
Very little muscle or
body fat
Narrow hips and
shoulders
Thin legs and arms
A narrow chest and
abdomen
Thin face and high
forehead
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Which somatotype?
All performers are made up of elements of these three
extreme somatotypes.
Most people have a mixture of mesomorphic, endomorphic
and ectomorphic characteristics.
A person’s somatotype can be graded using a scoring system.
They are given 3 scores between 1 and 7, according to how
well they conform to each of the extreme somatotypes.
1 is a low score, 7 is a high score. For example:
1, 7, 2
Low endomorph
High mesomorph
Low ectomorph
What would a person with this score look like?
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Mesomorph
Most sports favour the
strong, muscular limbs
and low body fat of the
mesomorphic shape.
The Australian swimmer,
Ian Thorpe, has a classic
mesomorphic body shape.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
© EMPICS Ltd
The mesomorphic shape
is the most common body
shape among elite
performers.
Which somatotype?
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Somatotypes in sport
Certain somatotypes tend to be found in certain sports.
The ideal somatotype for a performer will depend on their
sport or event. In some cases, the position that they play in
a particular sport might
also be important.
Consider, for example,
the various body sizes
and shapes in a rugby
team.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Somatotypes in sport
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Altering body shape
Body type is largely determined by the genes you inherit
from your parents.
However, you can alter your somatotype by training, or
by changing your diet.
Eating more
and/or exercising
less will increase
your body fat,
making you more
endomorphic.
Weight training
will increase
muscle size,
making you
more
mesomorphic.
Eating less and/or
exercising more
will decrease your
body fat, making
you more
ectomorphic.
Dramatically changing your body shape is
difficult and can be damaging to your
health. Big changes are hard to maintain.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Weight
Every individual has their own optimum weight – the weight
at which they are healthy and able to perform at their best.
Your optimum weight depends on a number of factors:
Height – In general, the taller you
are, the more you should weigh.
Sex – Men usually have a higher optimum
weight than women of the same height.
Bone structure – Some people have
bigger bones and are naturally heavily
built, without being overweight.
Muscle girth – People with big, well-developed
muscles can weigh a lot without being overweight.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Overweight and overfat
A person who is significantly heavier than their optimum
weight is classed as overweight.
Being overweight is not necessarily harmful as it is possible
for the extra weight to be in the form of muscle.
However, if the extra weight is in the form of fat, then the
person is classed as overfat. This means that an abnormally
large percentage of their body is composed of fat.
Men are overfat if
more than 19% of
their body is fat.
Women are overfat
if more than 25% of
their body is fat.
Being overfat can affect your health, increasing
your risk of heart disease and other illnesses.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Obesity
Obese people are people who are extremely overweight.
Men are obese if
more than 25% of
their body is fat.
Women are obese
if more than 30%
of their body is fat.
Obesity is very damaging to health. As well as heart disease,
obese people run a higher risk of diabetes, varicose veins,
menstrual disorders, infertility, skin diseases, liver disorders,
cancer, joint problems and even depression.
Very obese people can be classed as morbidly obese,
meaning that they are so overweight that it is endangering
their life.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
© EMPICS Ltd
Obesity
Being obese does not stop you from becoming a
successful performer in some sports. Andy Fordham
was World Darts Champion in 2004.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Underweight
Being significantly below your optimum weight can
also be bad for you.
The body needs some fat reserves – underweight
individuals have a lower resistance to infection and can
find it difficult to recover from illness. They may feel
constantly tired and bone strength may deteriorate.
Underweight women can have trouble getting pregnant.
It is recommended that:
men should not
have less than
5% body fat.
women should not
have less than
10% body fat.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Weight charts
A rough way to
determine
whether
someone is
overweight or
not is to use a
height-toweight chart.
The results are
fairly arbitrary and
take no account
of muscle bulk
and frame.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Body Mass Index (BMI)
Another way of estimating body fat is to calculate an
individual’s body mass index (or BMI).
BMI is calculated by dividing the individual’s weight (in
kilograms) by their height (in metres) squared.
To Convert:
BMI =
weight (kg)
height2
154 lbs x 1 kg__ = 70 kg
2.2 lbs
Math is great!
So, a person who weighs 70 kg and is 1.70 m tall has
a BMI of:
70
= 24.2
2
1.70
A BMI of 19–25 is considered healthy.
Over 30 is obese.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Body Mass Index (BMI)
BMI is not an appropriate test for everyone. It is calculated
using a person’s height and weight only, so like the chart,
the result does not take account of build and lifestyle.
Why do you think that a bodybuilder
might be classed as too heavy by a BMI
test, despite having very little body fat?
Under what circumstances could a
person with too much body fat be
classed as normal by a BMI test?
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Excess Body Fat and
Wellness

Increased risk of chronic disease and
premature death; associated health
problems include





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Unhealthy blood fat levels
Impaired heart function
Heart disease and hypertension
Cancer
Impaired immune function
Gallbladder disease
Kidney disease
Skin problems
Sleeping problems
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
What shape are you?
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Body Fat Distribution and
Chronic Disease

Location of fat is important to health

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People who gain weight in the abdominal area
= “apples;” this group has an increased risk
of coronary heart disease, high blood
pressure, diabetes,
and stroke
People who gain weight
in the hip area= “pears”
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Problems Associated with
Very Low Levels of Body Fat

Too little body fat is associated with
reproductive, circulatory, and
immune system disorders
Less than 10–12% for women
 Less than 5% for men

Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Female Athlete Triad

A condition consisting of three
interrelated disorders
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Estimating Percent Body Fat

Skinfold
measurements: Folds of
skin are measured with
a caliper. The
measurements are used
in equations that link
the thickness of
skinfolds to percent
body fat calculations
made from more
precise experiments.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Estimating Percent Body Fat

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Underwater weighing: An individual is
submerged and weighed under water.
Percentages of fat and fat-free weight are
calculated from body density.
The Bod Pod: The amount of air displaced by
a person in a small chamber is measured by
computerized sensors.
Bioelectrical impedance analysis (BIA): A
small electrical current is sent through the
body, and the resistance of the body to it is
recorded. The resulting estimates of how
much water is in the body can be used to
determine body composition.
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Assessing Body Fat
Distribution
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Disease risk increases with total waist
measurement of more than
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40 inches for men
35 inches for women
Disease risk increases with total waist-tohip measurement above

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0.94 for young men
0.82 for young women
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6
Setting Body Composition
Goals
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If fat loss would benefit your health, set a
realistic goal in terms of percent body
fat or BMI
If you have underlying health issues,
check with your physician before setting a
goal
A little weight loss at a time can be very
beneficial; focus on a healthy lifestyle
including proper diet and exercise
Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 6