Energy Systems

Energy Systems

1. Role Of ATP in Exercise

   • Body contains continuous supply of energy through use of adenosine triphosphate which is the energy currency of the body
   • ATP is a molecule that stores and releases chemical energy for use in cells. When ATP is broken down it gives energy for immediate muscle contractions.
   • ATP consists of one adenosine and three phosphate groups. Formed by a reaction between an adenosine diphosphate molecule and a phosphate. Energy is stored in the chemical bonds in the molecules. When the bond is broken energy is released
   • Muscles have very small amounts of ATP stored in them so to replenish ATP quickly the body has to use a number of other systems as well

2. ATP-CP System in Exercise

   • Anaerobic so does not require oxygen
   • Important during sports for the sudden and powerful movements such as shot put as muscles can use ATP without having to wait for oxygen
     • ATP-CP system only supports high intensity exercise for short periods of time
   • A muscle cell has a small amount of ATP that can be used immediately but can only last about 3 seconds.
     • To replenish ATP levels quickly muscle cells contain a high energy compound called creatine phosphate, when the bond is broken the energy it releases is transferred to ADP to resynthesise ATP

3. Lactate System in Exercise

   • Short term energy system and is used to meet energy requirements of higher intesnity over a longer period such as 400m race
     • when the body does not need to use the glucose for energy it stores some of it in the liver and muscles where it is easily accessible for energy production and is known as glycogen
   • Anaerobic process therefor does not require oxygen
   • ATP is made by the partial breakdown of glucose and glycogen through the process of anaerobic glycolysis. allows for 60-90 seconds of maximal work
   • By product of anaerobic glycolysis is lactic acid with a recovery time of 8 minutes
   • Anaerobic glycolysis - Brekas down liver and muscle glycogen stores without needing oxygen, this releases energy which can be used to resynthesise ATP.
     • Breakdown of glucose produces 2 ATP molecules
     • Breakdown of glycogen produces 3 ATP molecules

4. Aerobic System in Exercise

   • Long term energy system. Produces carbon dioxide and water which does not affect the muscles ability to contract
     • Production occurs in the mitochondria of the muscle cells. The system relies on the breakdown of carbohydrates and stored fats to produce energy
   • Production of energy within the aerobic system is slow to engage because it takes a few minutes for the heart to deliver oxygenated blood to working muscles
     • Examples of sports include long distance running, swimming or cycling events
       • Aerobic Glycolysis - first stage of aerobic metabolism, it converts carbohydrates into pyruvic acid using oxygen. breakdown takes 10 chemical reactions which is why it is slower to deliver energy
     • Krebs cycle - second phase in the process or anaerobic metabolism takes place in the mitochondria. the pyruvic acid enters the mitochondria resulting in 2 ATP being produced with carbon dioxide and hydrogen being made as waste
   • ETC - Most important process where most ATP is created this being 34 molecules from glucose.
   • Overall 38 molecules of ATP from one molecule of glucose recovering between a few hours to a few days

5. Adaptations of the Energy system

   • Increased Creatine Stores
     • Increased Tolerance to Lactic Acid
       • Increased use of Fats as energy source
   • Increased Storage of Glycogen
   • Increased Numbers of Mitochondria

6. Additional factors affecting Energy Systems

   • Diabetes and hypoglycaemic attack
     • if you have diabetes your body cannot use glucose properly so it builds up in the blood and cannot be used
     • Hypoglycaemia is an abnormally low level of glucose in your blood meaning you wont have the energy to carry out activities warning signs include sweating or shakiness
   • Childrens lack of lactate system
     • children are still growing and developing therefor the lactate energy system will not be fully developed in childrens bodies