Energy systems - Mrs N Benedict

Energy systems Learning outcomes: All are able to demonstrate understanding of the relationship between OBLA and VO2max Most are able to explain the third energy system (the aerobic system) Some can analyse the causes of fatigue Some can apply their knowledge in detail to exam questions. Starter Activity Complete the Anaerobic crossword

Using your homework complete the exam questions on OBLA and VO2max Starter Activity Using mini white boards answer the following questions. What is another term for the maximum volume of oxygen that can be consumed by the muscles per minute? Name an accurate method to measure this? State one factor that can affect this?

At what point does OBLA typically occur? Trained endurance performers can delay OBLA until what % of their VO2max? What is the name of the process that helps remove lactic acid and maintain blood and muscle pH? Name a factor that influences the rate of lactate accumulation. Homework Complete Energy systems WS3 questions and summary sheet. Complete Revise as you go questions.

Complete flipped learning activity on Recovery Aerobic system Low intensity activities with a duration of longer than 1-2 minutes use the aerobic system The aerobic system is a complex chain of events consisting of three stages. Stage 1: Glycolysis Occurs in the

sacroplasm Aerobic conditions so no lactic acid produced Pyruvic acid converted to acetyl coenzyme A (CoA) the energy released from the breakdown of each molecule of glucose is used to make two molecules of ATP

Stage 2: Krebs Cycle Takes place in the matrix of the mitochondria hydrogen is removed and taken to electron transport system carbon dioxide is produced as a waste product The energy yield is two molecules of ATP

Stage 3: Electron transport chain It occurs in the cristae of the mitochondria Water is formed (hydrogen ions and electrons combine) The energy yield is 34 molecules of ATP

Mini plenary Complete the diagrammatic representation of the aerobic pathway . Equation to summarise: C6H12O6 + 6O2 6CO2 + H2O + ENERGY ENERGY 38ADP + 38Pi ADP + 38ADP + 38Pi Pi 38ADP + 38Pi ATP Aerobic System Advantages

Disadvantages More ATP can be Cannot provide energy produced aerobically than anaerobically (36 rather than 2ATP) Body has enough stores of muscle glycogen and triglycerides to exercise

for several hours No fatiguing by products to resynthesise ATP in the immediate short term Transport of fatty acids is slow and requires about 15% more oxygen to break down than glycogen Endurance athlete needs

to use a combination of glycogen and fatty acids. 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 Energy systems Learning outcomes: All are able to demonstrate understanding of the relationship between OBLA and VO2max Most are able to explain the third energy system (the aerobic system) Some can analyse the causes of fatigue Some can apply their knowledge in detail

to exam questions. The Recovery Process 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.