This document discusses human energy systems and how the body converts food into energy for movement and activity. It covers the three main energy systems - ATP-PC, anaerobic, and aerobic. The ATP-PC system provides immediate energy through phosphocreatine stores but lasts only 10 seconds. The anaerobic system breaks down glucose without oxygen and fuels activity for 10 seconds to 3 minutes. The aerobic system uses oxygen to break down carbohydrates, proteins, and fats, fueling longer duration lower intensity activities. Carbohydrates, proteins, and fats are all sources of stored energy and calories that can be broken down to synthesize ATP through cellular respiration.

1. ENERGY
FOR
MOVEMENT
By: Norieta G. Langpawen

2. What is energy?
 Energy supports activities of the human body.
Energy is measured either in calories or joules.
Energy in our diet mainly comes from carbohydrate
protein and mainly fat.
The amount of energy needed for healthy individuals
takes account of various factors such as age, gender,
body weight , and activity level.

3. ENERGY FOR MOVEMENT
• All body movements
(voluntary and
involuntary) require
the muscles to
contract, for this, we
need energy that came
from food converted
in the form of ATP
(energy currency).

4. For our bodies to function, even at rest, we need
energy. This energy is derived from the food we eat,
which is used to make ATP (Adenosine Tri-phosphate).

5. What is this?
 This is the
MITOCHONDRION, a
tiny cellular structure that
turns chemical fuel
(carbs, protein, fat) into
cellular energy (ATP)

6. Adenosine Triphosphate (ATP)
• Our body stores energy in the form of Adenosine Triphosphate.
• ATP is made of 1 Adenosine molecule 3 phosphate molecules.
• All energy for cellular activity comes from ATP.
ADENOSINE P
P
P ATP

7. P P P
FOOD
P P
P
Energy for Cellular Work
Energy for Cellular Work
P
P
ATP
AMP
ADP
• When energy is released,
adrensine phosphate loses
a phosphate due to bond
breaking, becoming
Adenosine Diphosphate.
ADP then loses a phoshate
becoming Adenosine
Monosphate.
• Each time the bond breaks,
energy is released.
ATP ADP AMP

8. ATP
• ATP is stored in our muscle, therefore it is readily
available when energy is required. HOWEVER, there is
a limited supply of ATP within muscle cell, only
enough for 2-3 sconds of maximal effort.
• Therefore, to keep supplying the body with energy,
ATP has to be RESYNTHESIZED through our
body’s energy system.

9. THE THREE ENERGY SYSTEMS
•ATP is re-generated through 3 different energy
systems.
1. ATP-PC system
2. Anaerobic System
3. Aerobic System
*Intensity and duration of the exercise and whether oxygen is present
decides which system is to be used to generate ATP.

10. WHAT IS ENERGY SYSTEM?
Physiological process that describes how the body converts
energy from food into ATP to fuel various activities. Specifically,
energy system is the process your body uses to transform carbs,
protein, and fat into a form of energy that cells can use to power
different activities like breathing, cycling, and running.
Energy is always lost in this process of recycling ATP, which is
why you need to provide your body with more energy (calories)
for it to keep recycling ATP.
Thus,body’s energy systems are responsible for ensuring your
cells have a steady supply of ATP no matter if you’re sleeping,
working at your desk, or sprinting.

11. 1. ATP-PC (PhosphoCreatine)
Energy source stored in muscle, therefore
readily available. (phosphocreatine) that is
taken in animal products like red meat and
fish.
Made without the presence of oxygen.
Immediate energy system as it generates a lot
of ATP in the blink of an eye but lasts for 10
secs at max intensity.
Provides the bulk of ATP during powerful or
explosive efforts. ex. 100m sprint and weight
lifting.

12. 1. ATP-PC (PhosphoCreatine)
• The ATP-PC system uses a
stored molecule in the
muscle called creatine
phosphate (CP) to
resynthesise ATP. It is the
breakdown of this molecule
that releases the energy
needed to rejoin the ADP
and free phosphate to form
ATP.

13. ADVANTAGES OF ATP-PC
SYSTEM
Phosphocreatine is stored in
muscle so it is readily available.
Generates a lot of ATP quickly.
DISADVANTAGES OF ATP-PC
SYSTEM
Phosphocreatine is stored in
LIMITED amount in the muscle, so
it is easily exhausted. (6-10 secs.)
Takes the longest to fully
recharge (3-5mins)
Fatigue occurs by inability to
continually re-synthesize ATP
from PC because PC supplies are
quickly exhausted.

14. 1. ATP-PC (PhosphoCreatine)
Some athletes may seek to extend the time they can use this
system through creatine supplements, but abdominal
cramps, bloating, and dehydration have been reported as
side effects by athletes.
How can this system be improved?
• Sprint Interval Training
• Pyometrics
• Weight Training

15. 2. ANAEROBIC SYSTEM
When you exercise beyond the limit of your ATP-PC system,
anaerobic system kicks in. (no oxygen)
This system is used for energy production in higher intensity
events lasting between 10 secs to 3 mins.
This system also releases energy quickly, so it can supply ATP for
high intensity short-term exercise such as 400m sprint and 100m
swimming.
Also referred to as the glycolytic system because it gets the
majority of its energy from the glycogen stored in your
muscles/liver and the glucose in your blood.

16. 2. ANAEROBIC SYSTEM
This system uses the energy from the breakdown of glucose
(sugar) stored in your liver to resynthesize ATP. You get glucose
from eating carbs.

17. ADVANTAGES OF ANAEROBIC
SYSTEM
Produces a lot of ATP that can
lasts for 3 mins.
Recharges quicky compared to
phosphocreatine system. (about
3 mins.)
DISADVANTAGES OF
ANAEROBIC SYSTEM
Produces Lactic Acid as
byproduct that quickly build up in
the blood and muscles that after 3
mins this causes fatigue.

18. 2. ANAEROBIC SYSTEM
When your muscles are making energy anaerobically, lactic acid is
created as a byproduct, then it build up in the muscle during
exercise. The body naturally clears lactic acid when it develops, but
it may not be able to keep up when the levels start to increase
rapidly.
Lactic acid build up are gone in about an hour.
Lactic acid does not cause muscle soreness, soreness is caused by
damaged during exercise which is normal.
During Lactic acid build up, decrease the intensity of exercise, rest,
and drink a lot of water to supply oxygen and helps flush out the
acid.

19. 3. AEROBIC SYSTEM
When you exercise beyond the limit of your ATP-PC and
Anaerobic system the AEROBIC Sytem comes into play.
This sytem uses oxygen to breakdown carbs, protein, and fats
needed to resynthesize energy.
Since this system uses oxygen to help resynthesize, it can
therefore used for activities that are long in duration like
marathon and cycling.

20. 3. AEROBIC SYSTEM
The aerobic system uses a combination of glucose, glycogen, and
body fat to generate ATP, with the exact ratio depending on how
intense the exercise is.
As your workout intensity rises, your aerobic system uses more
and more glucose and glycogen to produce ATP and less body fat.
As your workout intensity lessens, your aerobic system uses more
and more body fat and less and less glucose and glycogen.
This is why many people believe low-intensity cardio is better for
fat loss than high-intensity cardio—it burns a greater percentage of
fat. However, higher-intensity cardio burns a lot more total
calories, which is what really drives long-term fat loss.

21. ADVANTAGES OF AEROBIC
SYSTEM
Produces a lot of ATP very
effeciently for a long time.
DISADVANTAGES OF
AEROBIC SYSTEM
Takes several minutes warm up
to produce substantial amount of
ATP.

22. Does not use oxygen to
resynthesize.
High Intensity/Short
Duration
Does not use oxygen to
resynthesize
High-Medium
Intensity/Short Duration
Uses Oxygen to
resynthesize
Low Intensity/long duration
Does not produce lactic
acid (alactic)
Produces Lactic Acid as
byproduct
Produces Carbon Dioxide
and Water as waste
Lasts for 6-10 secs
Recharges for about 5 mins
Lasts for 10secs-3mins
Recharges for about 3 mins
Lasts for 3mins-above
Fastest to recover
Uses the stored Creatine
Phosphate in the muscle to
resynthesize ATP.
Uses the energy produced
by the breakdown of
Glucose stored in the liver
and muscles to
resynthesize ATP.
Uses oxygen to breakdown
carbs, protein, and fats to
resynthesize ATP.
Used for activities like
weightlifting, swaying a bat
and 100m sprint.
Used in activities like 400m
sprint and 100m swimming
Used for activities like
marathon, cycling, and
rowing.

24. SOURCES OF ATP
1. Carbohydrates
2. Protein
3. Fats
1 gram of Carb = 4 calories = 38 ATP
1 gram of Protein = 4 calories = 38 ATP
1 gram of Fat = 9 calories = 86 ATP
Carbohydrates, protein, and fat
provide stored energy in the form of
calories. The process of unlocking this
stored energy is called cellular
respiration.

25. CARBOHYDRATE
Body’s most efficient fuel source
Vital during high intensity exercise when the body cannot process enough oxygen
to meet its needs.
If people consume more carbohydrates than they need at the time, the body
stores some of these carbohydrates within cells (as glycogen) and converts the
rest to fat.

26. CARBOHYDRATE
Carbohydrates are the bodies preferred source of food energy for the
synthesis of ATP.
Once digested carbohydrates are broken down into glucose and chemical
reactions involving glucose then produce ATP.
Glucose is always present within the blood as it circulates and provides a
readily available source of energy.
Too much glucose in the blood is not healthy however as it becomes thick and
sticky, making it harder to flow through small blood vessels.
So to ensure the blood glucose levels are healthy excess glucose that is not
needed immediately to produce energy for the body is converted into a
substance called glycogen and this is stored in the muscles and liver. When
needed, glycogen can then be converted back to glucose for energy.

27. PROTEIN
• Protein contains four calories per gram and again provides energy at a
much slower rate than carbohydrates.
• Protein only makes a small contribution to energy production.
However, it can become a more significant energy source under
periods of prolonged starvation or in ultra endurance events where
other energy sources become severely depleted.
• Protein is converted into amino acids. Amino acids are normally
responsible for the growth and repair of body tissue but they can also
be converted into glucose or into other substances used by the body.

28. Fat
• Fats are broken down into free fatty acids (FFA) and triglycerides which can
produce ATP through chemical reactions.
• Fatty acids either circulate in the blood or are stored as triglycerides in adipose
tissue and muscle.
• Fat is a very energy dense nutrient, one gram of it provides nine calories of
energy.
• Despite the large quantity of available energy that fat has it provides this energy
at a much slower rate than carbohydrate. This is because the chemical reactions
required for its breakdown are much more complex and time consuming.
• It is important to note that an excess consumption of any or all of these food
sources (carbohydrates, fats or proteins) does not result in more energy being
produced, rather it results in the consumed excess being converted to and stored
as adipose (fat) tissue.

29. CARBOHYDRATES
(Glucose)
PROTEIN
(Amino Acids)
FAT
(Fatty Acids
/triglycerides)
 1 g= 4cal=38 ATP  1 g= 4cal=38
ATP
 1gram=9
cal=131ATP
 Fastest to
breakdown
supply energy
 Does not
actually supply
energy,but
some amino
acids are
converted to
glycogen
 Slowest to
breakdown to
supply energy

31. The higher the intensity of the exercise the quicker the
anaerobic systems will be depleted. For exercise to
continue once the anaerobic systems have become
significantly depleted the intensity of exercise needs to
drop to a level that allows the aerobic system to provide
enough energy, as can be seen in the following table.

32. Energy Requirements of Physical Activities
• Our body requires energy, even at rest. The energy
or calories burned during rest and when we are
active is known as our metabolic rate. The amount
of energy our body requires depends on a number
of factors including things like our height and
weight, body composition and activity levels.
• Energy is measured in calories, and calories are
gained from the foods we eat. If we consume the
same amount of calories that we use our weight
will remain constant. This is known as an energy
balance. If we consume more calories than we use
then we will put on weight and vise versa as we no
longer have an energy balance.
• Different activities burn different amounts of
energy or calories. The table below is based on the
number of calories someone weighing 60kg would
burn in an hour:

33. END