BODY COMPOSITION - Missouri Western State University
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Transcript BODY COMPOSITION - Missouri Western State University
BODY
COMPOSITION
Chapters 18
*Your 10 point quiz is the very next
slide!!
OVERWEIGHT VS.
OVERFAT
Overweight is based on height-weight
tables and says nothing about body
composition.
Overfat actually takes into account the
total body composition of lean and fat
tissue.
FAT DEPOSITS
Essential fat (around 3%) is needed to
live (metabolic functioning, hormone
production, insulation, etc.).
Females have additional sex-specific
essential fat (9%) for pregnancy and
lactation.
Everything else is storage fat (visceral
+ subcutaneous)
FFM and LBM
Fat free mass is equal to body mass –
fat mass.
Lean body mass includes essential
fat.
WAYS TO MEASURE
Hydrostatic Weighing
Bod Pod
Skinfolds
Girth measurements
Bioelectrical Impedence Analysis
Dual Energy X-ray Absorptiometry
BODY MASS INDEX
Weight in kilograms divided by height
in meters, squared
Overweight is a BMI between 25-29.9
Obese is a BMI >29.9
WHAT IS OBESE?
Using body fat percentages as an
indicator, >20% in males and >30% in
females is considered obese.
“Healthy” is typically taught in PED
101 as 10-15% for males, and 1822% for females.
LOCATION OF FAT
For health reasons, the pattern of fat
deposition appears to be important.
Visceral (intra-abdominal) adipose
tissue is related to:
Hyperinsulinemia
Insulin resistance/intolerance
Hypertriglyceridemia
Reduced HDL
WAIST TO HIP RATIO
>.8 for women and >.95 in males
indicates an increased risk for heart
disease.
THEORIES BEHIND
OBESITY
The easy one: we eat too much.
Calories taken in exceed calories
expended. Portion sizes in
restaurants have gone up, and
television/computer/games have
replaced exercise. PE courses are
the first to go in K-12.
GENETICS
Genetics may account for 25% of the
differences between individuals.
30% is from cultural transmission.
Leptin (satiety hormone) may be
lacking in some (ob gene mutation),
plus blunted thermal response to
eating and depressed metabolism.
NUMBER OF FAT CELLS
Some people have more fat cells than
others. These fat cells always have a
minimum amount of fat in them (they
never go away unless sucked out)
We add fat cells (hyperplasia) during
the last trimester, the first years of life,
and the adolescent growth spurt. We
can make new fat cells if severely
obese.
Usually fat cells just hypertrophy.
SET POINT THEORY
The body tends to want to stay at a
level of fatness.
If overfed, it takes time to gain weight
through an increased metabolism
If underfed, metabolism is reduced to
conserve the fat we have
LOSING FAT
To lose fat, the energy equation must
be tipped to insure more calories are
being burned than consumed.
The calories being burned come from
3 major sources:
Resting and basal metabolism (70%
of calories)
Exercise/activity (20% of calories)
Thermal effect of digestion (10%)
RESTING METABOLISM
Directly related to amount of muscle.
Aerobic exercise influences resting
metabolism in that after exercise, the
metabolic rate is elevated for up to 5 hours.
Drugs also affect resting metabolism:
Nicotine
Caffeine
Ma Huang (ephedrin)
RESTING METABOLISM
Also affected by climate: warmer
weather may increase from 5-20%
Extreme cold may double or triple the
metabolic rate.
THERMAL EFFECT OF
FOOD
Protein is the highest (up to 25% of
food calorie value may be used to
digest)
Carbs are next
Fats are last (3% of value to digest
and store)
EXERCISE AND FAT LOSS
The total number of calories
expended in creating the caloric
deficit, not the percentage mixture of
macronutrients oxidized, determines
the effectiveness of exercise in weight
loss.
EXERCISE AND FAT LOSS
Aerobic exercise, where a minimum of 200400 kcals are expended, is recommended,
coupled with a resistance training program
to at least maintain the muscle mass
already existing.
The longer the better (up to 60 minutes)
Work on volume of exercise (days per week
x time exercising)
AEROBIC EXERCISE
Start slow and work up. Time and
frequency are more important than
intensity.
Stay as active as possible throughout
the day (compensation for exercise?)
Look at it as a lifetime behavioral
change.
Realize pitfalls and shortcomings
CALORIC RESTRICTION:
EATING TO LOSE
Don’t drop calories too far (1200 for
men and 1000 for women
Keep carbs high—you’ll keep more
muscle, burn more fat, and have the
energy to exercise.
Don’t eat within 5 hours of going to
bed (light snack is okay)
Don’t deprive yourself—you have to
live with this the rest of your life.
GAINING WEIGHT
Resistance training. Positive caloric
intake of 2400 calories.
Increase caloric consumption (not the
mix of foods—those must remain
within the healthy mix of foods); can
adjust protein upwards slightly.
Procedures for weight
control
Liposuction
Rou-en-Y
Lap band
Jaw Wiring