The document discusses the three main energy systems - ATP-PC system, lactic acid system, and aerobic system. It provides examples of how each system is used in different sporting events like sprinting, long distance running, and field events. The ATP-PC system provides energy over seconds, the lactic acid system over minutes, and the aerobic system provides virtually unlimited energy through oxygen. The first law of thermodynamics states that energy cannot be created or destroyed, only changed from one form to another.

1. Energy Systems
Christie Woods

2. What is ATP and energy?
ATP: ATP – or Adenosine Triphosphate – is the primary energy carrier in all living organisms on earth.
Microorganisms capture and store energy metabolized from food and light sources in the form of ATP.There are
two ways the body can make ATP, one through the anaerobic pathway which is with the absence of oxygen
present.A sporting example would be on a 100m sprint when the athlete is not needing large amounts of oxygen
to complete the race.Another way the body produces ATP is aerobically so this will involve oxygen.So as a
sporting example it would be needed in a long distance race like the 1500m.Aerobically , the ATP is given off
slower comparing to anaerobically as the runner does not need a large supply of it as the race is long and there is
oxygen present.However anaerobically, ATP is given off quicker as it is in high demand over the short distance
with the absence of oxygen.
Energy:Energy is a property of objects which can be transferred to other objects or converted into different
forms.(Wikipedia,2016)The main source we get our energy from is from eating foods such as
proteins,fats,carbohydrates and many others.This is what contributes to keeping us alive and healthy.These
foods convert into the energy we use everyday (ATP).This energy from the foods act as a fuel to the working
muscles to enable movement.

3. Thermodynamics
2 3
Heat energy is
reserved in the sun
and light energy
shines on the earth to
the grass and creates
chemical energy.
The cow eats the grass
containing the chemical energy
carbohydrates and this helps the
cow to grow and move on a daily
basis.
The human will eat the
carbohydrate chemical energy
from the cow and this will
produce ATP energy in our
bodies to help us to move.
The first law of thermodynamics, energy is neither created
nor destroyed, just changed.

4. What do we need energy for?
1. Circulation-Energy is needed to give our bodies the power we need to move so as an example the
blood we circulate in our bodies is through the use of energy pumping the blood around and if we had
no energy blood would not be used effectively.
2. Digestion of foods-Firstly we use the energy to digest the foods we eat but once we have digested this
food,the energy from this is then converted into chemical energy.
3. Muscular contractions and movement-Energy is needed to contact and relax the muscles needed for
basic movements.The energy is pumped around the body and through to the muscles to enable our
joints to move freely.
4. Transmission of nerve impulses-The nerve impulse is the wave of electrical activity that passes from
one end of a neuron to the other end and this also contributes to movement as the nerves are
attached to the vital organs in the body.
5. Repairing and replacing tissues-Proteins help to grow and repair tissues so we need the energy to be
able to keep on top of the circulation so our bodies will benefit from them proteins.

5. Overview of the 3 energy systems
Lactic Acid System-The lactic acid system fuels us for a very short amount of time as it is needed in order to
fuel the muscles used if at high intensity like in long distance running as the muscles are used at high
intensity throughout the race.
Aerobic Energy System-The aerobic system includes oxygen and is a very complex system as ATP is
required to be present so therefore mass amounts of this needs to be produced at the same time in the
system.
Phosphocreatine System-This system is needed to produce the constant flow of the ATP we need to have
provided on a daily basis as it is used to fuel the metabolism and also many other vital systems within the
body to help to keep us living a healthy life.

6. Lactic Acid System
The lactic acid system is shown throughout anaerobic respiration.This is the point at which the body is working without the
presence of oxygen to produce the maximum amount of power in a short period of time, sporting examples including sprinting
or jumping.Your muscles need the oxygen to enable movement all day long so if there is no oxygen,lactic acid will build up as
the muscles are in need of the oxygen in order to move.The substance made during this process is called lactate.The body has a
limited store of about 85 grams of ATP and would use it up very quickly if we did not have ways of resynthesising it. This is one of the
three systems that produce energy to resynthesise ATP: ATP-PC, lactic acid and aerobic.
This is made during the point at which where there is not enough oxygen in the muscles to enable movement.In one hand, your
body is able to make energy out of this buildup of lactate but as this energy is made, more lactic acid is made of a higher
amount comparing to the production of energy than you can get rid of so it will have side effects of your legs feeling heavy and
it will make movement very difficult causing you to stop moving in order to try and recover to continue.The process of lactic
acid removal takes approximately one hour, but this can be accelerated by undertaking an appropriate cool down that ensures
a rapid and continuous supply of oxygen to the muscles.

7. Aerobic energy system
The aerobic energy system utilises proteins, fats and carbohydrate (glycogen) for resynthesising ATP. This energy system can
be developed with various types of running.This system utilises fats, carbohydrates and sometimes proteins for re-
synthesising ATP for energy use.It produces far more ATP than either of the energy systems but it produces the ATP at a much
slower rate, therefore it cannot fuel intense exercise that demands the fast production of ATP.While the aerobic energy
system doesn’t produce nearly as much power as the other systems, its key feature would be that the capacity of producing
ATP is virtually limitless as it is never ending.
As a sporting example , a long distance runner should have the correct amounts energy throughout the race via the many
different types of energy systems like the aerobic energy system , however the ATP in this system will continue to fuel the
needed muscles so the runner is able to continue as the energy through this is never ending.

8. Phosphocreatine
The muscles of the body function through the use of ATP, or adenosine triphosphate, to power contractions. When one
molecule of ATP is used in the contraction process, it is hydrolyzed to ADP, adenosine diphosphate, and an inorganic
phosphate. The muscles’ limited ATP supply is used very quickly in muscle activity, so the need to regenerate ATP is
essential. One of the ways that this ATP supply is regenerated is through the molecule creatine phosphate (or
phosphocreatine). In the process of regeneration of ATP, creatine phosphate transfers a high-energy phosphate to ADP.
The products of this reaction are ATP and creatine. Creatine phosphate can be obtained from two sources: ingestion of
meat and internal production by the liver and kidneys.
Creatine and creatinine (fromed from the metabolism of creatine) waste is removed from the body through the kidneys and
urinary system. Adenosine Triphosphate (ATP) stores in the muscle last for approximately 2 seconds and the resynthesis of
ATP from Creatine Phosphate (CP) will continue until CP stores in the muscles are depleted, approximately 4 to 6 seconds.
This gives us around 5 to 8 seconds of ATP production.The recovery time gets quicker every time you do intense exercises
as your body becomes more used to it and it will indicate you are getting fitter.
A sporting example would be in Javelin and various other field events that need lots of ‘quick’ power that is already stored in
the muscles.

9. 100m and 1500m analysis
Above is a graph showing the changes in velocity for a 100m runner.At the start the runner has a dramatic acceleration as from the
graph the line is very steep from 0m to around 30m in distance.At around the 30 metre point the line begins to flatten out and continue
at a certain height, this is because the runner is at a constant speed until around 80-90 metres.From that point, you can begin to see a
dip or a drop from the line and this shows that the runner is slowing down towards the last few metres of the race until they come to a
stop at 100m as they have finished.

10. 100m and 1500m analysis
At the start of the 100m race the main energy system we use is the ATP that is stored in the muscles as we have just started
the race and require no other energy just yet.In the next 7 or 8 seconds of the race this ATP energy is all used up and you enter
the lactic acid system which will allow you to gain and have enough energy to finish off the race as you will be running at a high
intensity.However it will not generate as much energy as the other systems as this is why there is a dip at the end showing in
the results,
Comparing a 100m race to a 1500m race there will be a significant difference in when these energy systems will need to be
used throughout.In a 1500m race at the very start,the first 100m will be quick and the optimum time to position in the
race.The ATP energy system is used first as it is applied immediately as it is already stored in the muscles ready for use.At
around the first bend you are able to go into your lactic acid system as you have not been able to gain enough oxygen at the
beginning of the race therefore you reach the lactic acid zone as it takes a while for the anaerobic system to actually kick
in.From laps 2,3 and 4 you will use the aerobic system as the pace at which you are running slows but is maintained and oxygen
is able to reach the blood.In the final 400m of the event , the pace will begin to increase again as you are wanting to finish the
race so the lactic acid system comes back up again as you are running at a high intensity.Towards the last 100m you will enter
the ATP system as it has been recovered in the race to give you the final push to the end