The document discusses the three energy systems - phosphagen, anaerobic glycolysis, and aerobic respiration - that provide energy for physical activity. The phosphagen system uses creatine phosphate to rapidly generate ATP for bursts of intense activity up to 30 seconds. Anaerobic glycolysis produces ATP without oxygen through glucose breakdown, fueling moderate intensity activity for up to 3 minutes. Aerobic respiration uses oxygen to slowly but sustainably produce ATP from carbohydrates and fats, fueling long duration lower intensity exercise. The document provides examples of which systems predominate in different sporting events.
2. What is energy?
• Energy is a property of objects which can be transferred to other
objects or to be converted into different forms.
• So in football, energy allows us to move our bodies and run and kick a
football. This is important in football because without energy our
performance will be affected with our work rate levels.
3. Where do we get energy from?
• Energy ultimately comes from the sun however our energy comes
from the food we eat. Our bodies digest the food we eat by mixing it
with fluids (acids and enzymes) in the stomach. When the stomach
digests food, the carbohydrate (sugars and starches) in the food
breaks down into another type of sugar, called glucose.
• We need energy to fuel our bodies internal functions, repair muscles,
skin and organs, builds and maintains cells and body tissues, and
supports the external activities that enable you to interact with the
physical world such as playing football. Water is your body’s most
important nutrient. Water helps facilitate the chemical reactions that
produce energy from food.
4. ATP
• The food we eat in the form of carbohydrates, fats and proteins, is
used as fuel for the reactions in the body that makes us ‘alive’. Called
adenosine tri-phosphate (ATP). There are essentially two mechanisms
for producing ATP, the aerobic and anaerobic pathways. ‘Aerobic’
means literally with oxygen, while ‘anaerobic’ means without oxygen.
5. The energy systems
Phosphagen
This system uses creatine phosphate and has a very rapid rate of ATP production. This phosphate is used to create ATP after
its broken down to release energy. ATP is stored in muscles in small amounts. Therefore its used in short term high intensity
activities lasting about 1 to 30 seconds in duration, such as sprinting, weight lifting or throwing a ball.
Anaerobic Glycolysis
Anaerobic Glycolysis does not require oxygen and uses the energy contained in glucose for the formation of ATP. Anaerobic
Glycolysis can produce ATP quite quickly for use during activities requiring large bursts of energy over somewhat longer
periods of time.
Anaerobic Glycolysis
This pathway requires oxygen to produce ATP because carbohydrates and fats are burned in the presence of oxygen. The
pathway occurs in the mitochondria of the cell and is used for activities requiring sustained energy production. This pathway
makes a slow rate of ATP production and Is used for a long duration of time.
It is important to remember that all three systems contribute to the energy needed for the body during physical activity.
6. ATP-PC System
• 1. initially ATP stored in the myosin cross-bridges (microscopic contractile parts of the muscle) is
broken down to release energy for muscle contraction. This leaves the by-products of ATP
breakdown: adenosine diphosphate (ADP) and one single phosphate (Pi) all on its own.
• 2. phosphocreatine (PC) is then broken down by the enzyme creatine kinase into Creatine and Pi
• 3. The energy released in the breakdown of Pc allows ADP and Pi to rejoin forming more ATP, this
newly formed ATP can now be broken down to release energy to fuel activity.
7. Lactic Acid System
• Lactic acid is produced during intense levels of exercise when the oxygen
demands of the muscle fibres increase beyond what the blood is capable of
delivering. To produce the energy needed, the body begins another process,
which works in the absence of oxygen.
• The anaerobic glycolysis (lactic acid) system is dominant from about 10–30
seconds during a maximal effort. It replenishes very quickly over this period and
produces 2 ATP molecules per glucose molecule, or about 5% of glucose's energy
potential (38 ATP molecules).
• Sports that use this system are 100m sprint in athletics and football.
• The lactic acid requires between 30 seconds and three minutes.
8. Aerobic Energy System
• It’s a respiration system that is used with oxygen.
• The aerobic system accesses a massive store of virtually unlimited energy. ... The
aerobic system produces far more ATP than either of the other energy systems
but it produces the ATP much more slowly, therefore it cannot fuel intense
exercise that demands the fast production of ATP.
• This potential is then used to drive ATP synthase and produce ATP from ADP and
a phosphate group. Biology textbooks often state that 38 ATP molecules can be
made per oxidised glucose molecule during cellular respiration (2 from glycolysis,
2 from the Krebs cycle, and about 34 from the electron transport system).
• The sports that use the aerobic respiration are the 1500m run in athletics and
cycling.
• It takes about 3 to 7 minutes to recover from aerobic respiration it depends on
how long the system is being used for.
9. 100 metre race
• At the beginning there is rapid acceleration because of the immediate energy system depletes and then
between the 30-40 metres the athletes then start using the short energy system also known as Anaerobic
respiration.
10. Energy Systems 1500 metre race
• In the first 100 metre the athletes body starts using the immediate energy
system, this allows the athlete to gain the optimal position.
• From the 100 metres to 1100 metres the pace slows because the athletes
body has started to use the short term and aerobic energy systems. This
allows them to maintain a steady pace.
• The final 400 metres sees that the pace has started to pick up, this is
because the body is still using the aerobic energy but now started to use
the short term energy system again.
• The final 100 metres sees the athlete going flat out to the finish line this is
because the athlete has started to use the immediate energy sytem again
and the athlete that saves their immediate energy until last the best will
win the rest.
