Energy Systems Flashcards
In the body the energy we use for muscle contractions comes from which chemical?
Adenosine Triphosphate (ATP)
ATPases is an enzyme that breaks down ATP. During this process energy is released and ATP is converted into what other chemicals?
Adenosine Di-phosphate (ADP) + Phosphate (Pi)
ADP is converted back to ATP through chemical reactions so it can be used again to supply energy for muscle contractions. What substance is found in the muscle that can be used to convert ADP to ATP quickly?
Phosphocreatine (PC)
Where is the muscle cell/fibre is PC stored?
Sarcoplasm
PC stores in the muscles are limited and can only be used to produce ATP for a short time. How long can PC stores be used for?
5-8 seconds
PC stores in the muscles can be replenished during rest or what type of exercise?
Low-intensity exercise, when additional oxygen is available
Name 3 athletic events that will use the PC stores predominately as the energy source.
Shot put Discus Long Jump High Jump Triple Jump Hammer Pole Vault 100m - if an elite athlete
In the ATP-PC system which enzyme detects high levels of ADP?
Creatine Kinase
What type of reaction occurs when Creatine Kinase breaks PC into Pi + C + energy and the energy from this process is used to bind Pi to ADP to form ATP?
Coupled reaction (energy required by one process is supplied by another process)
How many ATP can 1 molecule of PC make?
1
Give 2 advantages of the ATP-PC System
ATP re-synthesised rapidly (provides a rapid source of energy for muscle contractions)
PC stores can be replenished quickly (30s = 50% replenished. 3min = 100% replenished)
No fatiguing by-products
Creatine supplements could be used to increase the time the energy source lasts.
Give 2 disadvantages of the ATP-PC System
There is only a short/limited supply of PC in a muscle cell (lasts up to 8s).
1 PC = 1 ATP so it isn’t very efficient
PC re-synthesis can only take place when additional oxygen is present (rest or low intensity activity)
ATP-PC system is an anaerobic (without Oxygen) process of making ATP. What is the other anaerobic process to make ATP?
Anaerobic Glycolytic System
When PC levels are low which enzyme is activated to start the anaerobic glycolytic process?
Glycogen Phosphorylase
In the anaerobic glycolytic system Glycogen is broken down in glucose by Glycogen Phosphorylase and then glucose is broken down into pyruvic acid by which enzyme?
Phosphofructokinase
When oxygen isn’t available pyruvic acid is broken down in to what chemical by the enzyme Lactate dehydrogenase?
Lactic Acid
The Anaerobic Glycolytic system can last up to 3mins. What two factors influence how long the system can last?
Fitness levels (poor Cardiovascular fitness (VO2max) = reduced time) Intensity of the exercise (high intensity = reduced time)
What fuel/food substance is used to make ATP in the anaerobic glycolytic system?
Carbohydrates stored in the body as glycogen
Where can glycogen be stored in the body prior to use in the anaerobic glycolytic system?
Muscles
Liver
How many ATP can be made from 1 molecule of glucose using the anaerobic glycolytic system?
2
The anaerobic glycolytic system can last up to 3 mins but peaks at about…
45s
Give 2 sporting examples of the anaerobic glycolytic system being used.
(any activity lasting over 8s and up to 3 mins)
200m
400m
Sprinting the length of the pitch to shoot in football
Doing a short hill climb in road cycling
Playing a fast long rally in Tennis
Doing a muddy hill climb in cross country running
Give 2 advantages of the anaerobic glycolytic system
- ATP can be re-synthesised quite quickly (few chemical reactions needed, no oxygen needed, stores of glycogen are ready in the muscles)
- Last longer than the ATP-PC system
- Lactic acid can be used as a fuel (pyruvic acid) or converted to glycogen if oxygen is present (during rest or lower intensity activity)
- It can be used for a quick extra burst of energy e.g. a sprint finish
Give 2 disadvantages of the anaerobic glycolytic system
Lactic acid is produced which causes fatigue (slows down chemical reactions in the body)
The amount of ATP produced from 1 glycogen molecule is a lot less that by using the aerobic system (2:36)
What are the 3 stages of the Aerobic energy system?
Glycolysis
Krebs cycle
Electron Transport Chain
Pyruvic acid is made during glycolysis and this can then be used in the Krebs cycle but first it is oxidised into two Acetyl groups. Which enzyme carries the Acetyl groups into the Krebs cycle?
Coenzyme A forming Acetyl-coenzyme A
Glycolysis takes place in the Sarcoplasm of the muscle cell/fibre, where does the Krebs Cycle and Electron Transport Chain take place?
Mitochondria
How many ATP are produced during the Krebs Cycle?
2
How many ATP are produced during the Electron Transport Chain?
34
How many ATP are made in the Aerobic energy system per 1 glycogen molecule?
36
What is this process called:
Acetyl groups combine with oxaloacetic acid forming citric acid. Hydrogen is removed from citric acid and oxidative carboxylation occurs and carbon and hydrogen are removed. The carbon form C02 and is breathed out and the Hydrogen enters the Electron Transport Chain.
Krebs Cycle (in the Aerobic energy system)
What is this process called:
Hydrogen is split into ions and electrons. Both are oxidised. Hydrogen ions form H2O (lost in sweat and urine) and electrons provide energy to re-synthesis ATP.
Electron Transport Chain
Glucose is one food source that can be used to make ATP and energy what are the other 2 food categories that can also be used?
Fats
Proteins
What is this process called:
Fatty acids are converted into acetyl coenzyme A which can then enter the Krebs Cycle.
Beta Oxidation
True or false:
In the aerobic energy system, fat produces less ATP per molecule than glycogen.
False
Fat needs more oxygen in order for it to be converted into ATP and energy. What type of exercise allows the predominant use of fats in the aerobic energy system.
Long duration, low intensity
Give 2 advantages of the aerobic energy system
- More ATP produced per molecule of Glycogen (36)
- No fatiguing by-products
- There are lots of stores of glycogen and triglyceride (fat) in the body so the energy system can last a really long time.
Give 2 disadvantages of the aerobic energy system
- Complex system - needs enough oxygen to be present to produce ATP and this can take a while to become available. Not an immediate source of energy.
- Fatty acid transportation to muscles is low and requires 15% more 02 to be broken down.
All energy system contribute during all types of activities but one will be the predominant energy source. Which is the predominant energy source for the 100m?
ATP/PC system
All energy system contribute during all types of activities but one will be the predominant energy source. Which is the predominant energy source used in cricket?
Aerobic Energy system
All energy system contribute during all types of activities but one will be the predominant energy source. Which is the predominant energy source for the 400m?
Anaerobic glycolytic system
All energy system contribute during all types of activities but one will be the predominant energy source. Which is the predominant energy source for a marathon runner?
Aerobic Energy system
Each energy system has a threshold at which point it can no longer meet the demands of the exercise and another energy system takes over. Which energy system(s) are used for activity lasting less than 10s?
ATP-PC
How long can the muscle stores of ATP last?
3s
Each energy system has a threshold at which point it can no longer meet the demands of the exercise and another energy system takes over. Which energy system(s) are used for activity lasting 8-90s?
ATP-PC and Anaerobic glycolytic system
Each energy system has a threshold at which point it can no longer meet the demands of the exercise and another energy system takes over. Which energy system(s) are used for activity lasting 90s to 3 mins?
Anaerobic glycolytic system and Aerobic energy system
Each energy system has a threshold at which point it can no longer meet the demands of the exercise and another energy system takes over. Which energy system(s) are used for activity lasting longer than 3 mins?
Aerobic energy systems
Which type of muscle fiber is most suited to using the aerobic energy system?
Slow twitch / type 1
Which type of muscle fiber is most suited to using the anaerobic glycolytic energy system
Fast twitch / type 11x
What is the definition of V02 Max?
The maximum volume of oxygen that can be taken up and used by the muscles per minute
On average how much 02 do we consume at rest per minute?
0.3 - 0.4 liters
On average what is the maximum amount of oxygen that an athlete can consume in 1 minute during exercise.
3 - 4 liters
When there isn’t enough oxygen being supplied to the working muscles at the start of exercise to meet demand the anaerobic glycolytic system is used. This creates an oxygen debt known as what?
Sub-maximal oxygen deficit
Working at a very high intensity means the demand of oxygen can’t be met and the athlete uses the anaerobic glycolytic energy system. This causes an oxygen debt known as what?
Maximal oxygen deficit
What does EPOC stand for?
excess post-exercise oxygen consumption
What are the 2 main components of EPOC?
Fast and Slow
What is the fast component of EPOC also called?
Alactacid component
What is the slow component of EPOC also called?
Lactacid component
State 2 things that occur during the fast component of EPOC
- Restore ATP stores in the muscles
- Re-saturate myoglobin with oxygen (takes 2 mins using 0.5 liters 02)
- Restore PC stores (50% in 30s (using 3 liters 02) and 100% in 3 mins)
State 3 things that occur during the slow component of EPOC
- Removal of lactic acid (30mins 50% removed using 5-6 liters 02).
- Replenish glycogen stores (1 hour to several days)
- O2 needed to keep breathing and heart rate higher (these muscle contractions require energy and therefore 02)
- Increase body temperature (this also helps keep respiratory rate high though)
What is the Cori cycle?
Chemical reaction where lactic acid is transported to the liver and converted into blood glucose and glycogen.