1. Energy Systems

Question 1

What is energy?

Answer 1

The ability to do work (joules)

Question 2

How many energy systems are there?

Answer 2

3 - 2 anaerobic, 1 aerobic

Question 3

What is ATP?

Answer 3

adenosine triphosphate - a molecule that stores and supplies energy

Question 4

What is chemical energy?

Answer 4

energy from food

Question 5

What is kinetic energy?

Answer 5

movement energy (skeletal muscle contraction)

Question 6

What is potential energy?

Answer 6

stored energy

Question 7

What is work?

Answer 7

force x distance (joules)

Question 8

What is power?

Answer 8

work performed over a unit of time (watts)

Question 9

What are the 4 substrates / food fuels?

Answer 9

PCr, glucose, lipids, amino acids

Question 10

What are the 2 anaerobic energy systems called?

Answer 10

ATP-PCr system, anaerobic glycolysis/lactic acid system

Question 11

What is the aerobic energy system called?

Answer 11

Aerobic glycolysis

Question 12

What source of energy is immediately available?

Answer 12

adenosine triphosphate (ATP)

Question 13

What does the breakdown of ATP result in?

Answer 13

energy for movement

Question 14

How long does ATP last for before needing to be resynthesised?

Answer 14

2-4 seconds

Question 15

What type of exercise is the ATP-PCr system used for?

Answer 15

very high intensity, 90-100% maximum heart rate

Question 16

What is the energy yield for the ATP-PCr system?

Answer 16

1mol ATP per 1 mol PCr

Question 17

What is PCr?

Answer 17

Phosphocreatine - compound stored in sarcoplasm in muscle

Question 18

What is creatine kinase?

Answer 18

An enzyme that detects high levels of ADP

Question 19

What is ADP?

Answer 19

adenosine diphosphate

Question 20

PCr breakdown equation

Answer 20

PCr > P + Cr + energy > ADP + Pi + energy > ATP

Question 21

How long does the ATP-PCr system last?

Answer 21

8-12 seconds

Question 22

How long does it take for PCr stores to be replenished?

Answer 22

3 mins for approx. 98% stores

Question 23

Advantages of ATP-PCr system:

Answer 23

-immediately available energy
-doesn’t produce lactic acid
-no waste products
-doesn’t require oxygen
-replenishes ATP quickly

Question 24

Disadvantages of ATP-PCr system:

Answer 24

-only a short store of energy
-long recovery time
-low ATP yield per PCr

Question 25

ATP-PCr system example sporting activities

Answer 25

-heavy weightlifting -100m sprint

Question 26

What occurs in the anaerobic glycolysis system?

Answer 26

breaks down glucose and glycogen to form ATP

Question 27

How is glucose stored in the body?

Answer 27

as glycogen in liver and muscle cells

Question 28

Anaerobic glycolysis equation

Answer 28

glycogen > glucose > (energy) > pyruvic acid > lactic acid > lactate/hydrogen ions

Question 29

Anaerobic glycolysis energy yield

Answer 29

2 mol ATP per 1 mol glycogen

Question 30

How do hydrogen ions affect exercise?

Answer 30

They cause fatigue by increasing the blood acidity causing enzymes to denature so their ability to catalyse reactions is slowed

Question 31

What type of exercise is the anaerobic glycolysis system used for?

Answer 31

High intensity, 2-3mins but peaks at 1 min

Question 32

Anaerobic glycolysis example sporting activities:

Answer 32

-netball -football -400m-800m race

Question 33

Advantages of anaerobic glycolysis system:

Answer 33

-higher energy yield - 2 ATP per 1 glycogen -oxygen not needed -lasts 3mins -rely on food to replace glucose -sustain high intensity activity for longer

Question 34

Disadvantages of anaerobic glycolysis system:

Answer 34

-peaks at 1min so inconsistent -produces lactic acid (H+ ions) -produces fatiguing by-product -takes longer to replenish ATP

Question 35

What 3 ways does the aerobic glycolysis system produce ATP?

Answer 35

-krebs cycle -electron transport chain -beta oxidation

Question 36

Aerobic glycolysis equation

Answer 36

glycogen > glucose > (energy - 2 ATP) > pyruvic acid > (O2) > acetyl coenzyme A > krebs cycle > (CO2, H- electrons) (2 ATP) > electron transport chain > (CO2, H2O) (34 ATP)

Question 37

aerobic glycolysis energy yield

Answer 37

38 ATP

Question 38

aerobic glycolysis example sporting activities

Answer 38

-marathon -long distance cycle

Question 39

What type of exercise is the aerobic glycolysis system used for?

Answer 39

low intensity, 5+mins

Question 40

advantages of aerobic glycolysis system:

Answer 40

-greater energy yield - 38 ATP -no fatiguing by-products -utilises 3 energy substrates/food fuels

Question 41

disadvantages of aerobic glycolysis system:

Answer 41

-generates ATP slowest -needs sufficient amount of oxygen

Question 42

aerobic lipolysis equation:

Answer 42

fats > glycerol + free fatty acids > acetyl coenzyme A > krebs cycle > electron transport chain (147 ATP)

Question 43

Energy continuum principle

Answer 43

Energy systems don't switch from one system to another There is a more predominant energy system however all are active but interchanging

Question 44

Factors influencing energy system used

Answer 44

-Intensity -Duration - fitness level

Question 45

Exercise intensity - influence on energy system

Answer 45

- the more intense the exercise, the more amount of PC and muscle glycogen (anaerobic stores) will be used - lower to medium intensity will predominantly use the aerobic system

Question 46

Exercise duration - influence on energy system

Answer 46

-If exercise is a longer duration it is more likely to use the aerobic system - shorter duration & higher intensity will use the anaerobic system

Question 47

Fitness level - influence on energy system

Answer 47

- Higher level of aerobic system will take longer to reach anaerobic threshold - when performing anaerobically there is limited energy available -If exercise continues performer will run out of anaerobic stores so return to aerobic & intensity will drop - greater anaerobic fitness means performer can work anaerobically for longer producing more powerful movements

Question 48

Food fuels / energy substrates

Answer 48

1. PCr → 90 - 100% max HR (ATP-PC), 8 - 12 secs 2. Glucose (carbohydrates) → 80 - 90% (anaerobic glycolysis) 3 mins, 60 - 80% (aerobic glycolysis) 5+ mins 3. Lipids (fats) → 40 - 60%, when glucose depleted 4. Amino acids (proteins), when glucose/lipids depleted