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
