BMR and Metabolism
What is METABOLISM?
Metabolism is the sum of all the
chemical processes that occurs
in organisms.
This includes not only how
quickly you digest your food,
but a whole collection of
processes in your body such as
building muscle, breaking down
glucose into usable energy,
formation of lipids from fatty
acids.
Two Types of Metabolism
1. Catabolism - the metabolic
breakdown of complex molecules
into simpler ones, often resulting in
a release of energy.
Ex: glucose for energy, burning fat,
breaking down tissue (aging)
Glycogen
glucose + energy
ATP
ADP + P
(releasing energy)
2.
Anabolism - the phase of
metabolism in which simple
substances are synthesized or
built up into the more complex
materials of living tissue
Ex: formation of protein from
amino acids, storing energy,
building muscle or tissue
Glucose + energy
glycogen
(ATP)
How Does It Work?
Metabolism is a constant
process
When people eat they take
in energy (in the form of
sugar), along with other
vital cell-building chemicals.
The body breaks the sugar
down so that the energy
released can be distributed
to and used as fuel by the
body's cells.
How Does It Work?
After food is eaten, enzymes
break proteins down into amino
acids, fats into fatty acids, and
carbohydrates into simple sugars
(e.g., glucose).
Amino acids and fatty acids can
also be used as energy sources
The compounds are absorbed
into the blood, which transports
them to the cells.
How Does It Work?
After they enter the cells,
other enzymes act to speed up
or regulate the chemical
reactions involved with
"metabolizing" these
compounds.
The energy from these
compounds can be released for
use by the body or stored in
body tissues, especially the
liver, muscles, and body fat.
How Does It Work?
Metabolism involves two
kinds of activities that go on
at the same time - the
building up of body tissues
and for energy and the
breaking down of body
tissues to generate more fuel
for body functions.
What is BMR?
BMR stands for Basal Metabolic
Rate
BMR is a measure of the rate at
which a person's body "burns"
energy, in the form of calories,
while at rest.
BMR can play a role in weight
gain.
What is BMR?
Ex: A person with a low BMR (who
burns fewer calories while at
rest) will gain more pounds of
body fat over time, compared to
a similar-sized person with an
average BMR who eats the same
amount of food and gets the
same amount of exercise
What Influences BMR?
Genetics
Health problems
Activity level – exercise
Body composition – lean muscle
Gender – men have more lean
muscle
Age – development vs. maintenance
Body Temperature/Body Size
Energy Supply - During time of
famine the body automatically
lowers its metabolic rate for a
“starvation diet”
How to Calculate BMR
1. Convert body weight kilograms
Weight in Pounds
2.2
2. Females - Multiply step #1 by
0.9
• Males - Multiply step #1 by
1.0
3. Multiply step #2 by 24 to get
basic kcals needed/day
Example
Jessie weighs 125 lbs. What is her
BMR?
1. Convert body weight kilograms
Weight in Pounds = 125 lbs/2.2 = 56.82
2.2
2. Females - Multiply step #1 by 0.9
56.82 x 0.9 = 51.14
3. Multiply step #2 by 24
51.14 x 24 = 1227.3 kcals/day
(BMR)
Finding Basic kcal
Needs
After find the BMR, you will adjust this
figure by adding the number of Calories
burned during daily activities.
Ex: Henry’s BMR is 1575. He ran for 1
hour on the treadmill. Each minute he
burned 10 Calories. What is his new
calorie requirement?
10 Calories x 60 minutes = 600 Calories
1575 + 600 = 2175
Problem #1
Jared and Sandy danced fast for 15
minutes. For each minute danced,
they each burned 4 calories.
Jared’s BMR is 1775 and Sandy’s
is 1552. What are their TOTAL
calorie requirements?
4 calories x 15 minutes = 60 calories
Jared = 1775 + 60 = 1835 calories
Sandy = 1552 + 60 = 1612 calories
1835 + 1612 = 3447 calories
together
Problem #2
Bethany weighs 112 pounds. Most
days she requires a 25% increase
in calories over her typical needs.
What is her new calorie
requirement?
BMR = 112/2.2 = 50.9
50.9 x 0.9 = 45.81
45.81 x 24 = 1099.4
1099.4 x .25 = 274.86
1099.4 + 274.86 = 1374.26
calories