Energy systems Learning outcomes: All are able to demonstrate understanding of the relationship between OBLA and VO2max Most are able to apply the recovery process to sport Some can analyse the causes of fatigue

Starter Activity During a marathon a performer uses the Aerobic system predominately. Explain how this system is used to resynthesis 38 ATP. (7 marks)

Answer 1. Majority produced by the aerobic system/oxygen 2. Glycolysis/Anaerobic glycolysis 3. Carbohydrates/glycogen/glucose 4. broken down into pyruvate/ pyruvic acid 5. Some ATP produced/2 ATP 6. Krebs cycle 7. Fats/triglycerides/fatty acids/glycerol 8. Beta oxidation 9. Oxidation of acetyl-coenzyme-A/Citric acid/ production of CO2 10. Electron transport chain 11. Water/H2O formed/hydrogen ions formed (H+)/ hydrogen/protons 12. Large quantities of ATP produced or resynthesised/34- 36 ATP

Homework Revise for Mock on muscles and energy systems Complete exam questions on Recovery process (WS1 and Practice makes perfect) Complete the Energy continuum worksheets (The energy continuum and WS4)

Use of fat in the Aerobic System b) (i) Very little fat is stored in muscle fibres, yet it remains a valuable source of energy during aerobic exercise. Explain how the fat stores of the body become available to working muscles. (3 marks) (ii) What are the disadvantages of using fat as an energy source during exercise?(3 marks) LOOK AT DIAGRAM ON P8 IN TEXTBOOK

Answer (b) (i) 1. Fat stores in adipose tissue/under the skin; 2. Converted to free fatty acids/glycerol in blood; 3. Lipolysis/lipases; 4. Oxidation in muscles (Beta oxidation) 5. Mitochondria/Krebs cycle; 6. (Limited) Triglyceride stores in muscle. 3 marks   (ii) 1. Cannot be used anaerobically/sprint-type activities; 2. Less efficient in energy yield per unit of oxygen/takes more oxygen to breakdown fat; 3. Requires carbohydrate to run; 4. Slower breakdown/transport; 5. Fat excess weight/increased energy required to perform a given task/harder to perform given task; 6. Fat reserves act as insulating layer preventing heat loss/leads to heat stroke. 3 marks

Hitting the wall. You have probably heard this expression what does it mean? Glycogen is depleted Body tries to use fatty acids as its only source Muscle spasms may occur.

Causes of fatigue Using a spider diagram use the knowledge you have gained over the last few weeks to explain some causes of fatigue. Glycogen depletion Lactic acid build up Reduced rate of ATP synthesis Dehydration Reduced level of calcium Reduced levels of acetylecholine

Causes of Fatigue Glycogen depletion – When glycogen stores are depleted athletes are said to ‘hit the wall’ as the body tries to metabolise fat. Lactic acid build up – Accumulation of Lactic acid releases hydrogen ions. Increases acidity of blood plasma. Inhibits enzyme action. Reduced rate of ATP synthesis – ATP & PC stores are insufficient. Dehydration – Effect blood flow to working muscles, Blood viscosity increases and blood pressure decreases Reduced level of calcium – Increase of hydrogen ions decreases the amount of calcium released. Reduced levels of acetylcholine – inhibits nervous impulses

The Recovery Process Using your notes prepared for homework write 5 questions that you could give to somebody to demonstrate their knowledge of the recovery process. Give to a partner and get them to answer them. Pass back and use a green pen to mark it.

The Recovery Process In pairs using your homework notes answer these questions: 1. What is meant by the term recovery? 2. Explain the term excess post-exercise oxygen consumption (EPOC). 3. What is the oxygen deficit? 4. What are the two stages of recovery? 5. Draw a diagram that illustrates the oxygen consumption during and following exercise.

The Recovery Process 1. the return of the body to its pre-exercise state. 2. the extra volume of oxygen consumed during recovery that enables the body to fully recover 3. When we start exercising insufficient oxygen is distributed to the tissues so the two anaerobic systems are used. The amount of oxygen that the subject was short of is known as the oxygen deficit. This is compensated by the surplus oxygen.

The Recovery process 4. The fast replenishment stage (alactacid) – Restoration of ATP and Phosphocreatine stores. Resaturate myoglobin. Takes 2 – 3 mins The slow replenishment stage (lactacid) – The removal of lactic acid (about 1hr). O2 also used to maintain cardiac and respiratory rates and normalise body temp. Replenish muscle glycogen stores.

The Recovery process 5.

Recovery process Use handout to ensure you fully understand this process. Add any additional notes required to this.

Beat the teacher Read the additional reading in pack and using your text book complete the beat the teacher activity sheet on Carbo loading and hypoglycaemia

Plenary Using the following terms explain the recovery process: EPOC Alactacid Lactacid Oxygen deficit Recovery