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Question 1

atp?

Answer 1

TP is the major source of energy that keeps every cell in the body going, including muscles.
ATP is a chemical fuel source, and consists of an adenosine molecule with three phosphates joined together in a row. Energy is released when one of the phosphates spills off, changing ATP into adenosine diphosphate (ADP) and inorganic phosphate (P i ). The chemical reactions that turn the energy contained in ATP into energy for use in muscular contractions can be summarised as follows.

Chemically ATP is bound to three phosphates
When a cell needs energy, it breaks the bond between the second and third phosphate groups, which releases a large amount of energy, forming ADP and P i .
When the cell has excess energy (from the breakdown of PC or nutrients), it resynthesis ATP from ADP and P i

Question 2

glycogen (carbohydrates)

Answer 2

Energy for muscular contraction stems first from muscle glycogen and then liver glycogen.
Carbs are digested and:
broken down into glucose in the bloodstream (transported via circulatory system)
Stored as glycogen in the muscles and liver
Excess stored as fats in the form of triglycerides within adipose tissue around the body

Glycogen is the bodies preferred fuel source in high-intensity exercises and in comparison to fat, as less they require less oxygen to break down to produce the same amount of energy.
It can be broken down with and without oxygen, this is known as aerobic Glycolysis (with oxygen) and one glucose molecule yields 36 to 38 ATP molecules whilst only 2 to 3 ATP molecules are produced without oxygen (anaerobic Glycolysis).
High-intensity aerobic exercise predominantly uses carbohydrates as its preferred fuel source.
Preferred source bc can be broken down with or without oxygen
CHO → Glucose → Bloodstream → Glycogen → Stored in muscles and liver to be used → Excess stored as fat around the body - adipose tissue

Question 3

Fats

Answer 3

Fats in the form of triglycerides are stored through the body in adipose tissue, under the skin and in the muscles.
Triglycerides are broken down into free fatty acids, which in turn are broken down aerobically to provide energy for movement.
Fats can only be broken down in the presence of oxygen (aerobically) however they are not the preferred fuel source as it puts added stress on the oxygen and transport and delivery system.
During sub-maximal prolonged exercise, fat becomes predominant as glycogen depletes. 1 triglyceride produces 450 ATP molecules, whilst 1 FFA (free fatty acid)produces 147 ATP molecules.
Fats → Free Fatty Acids→ Bloodstream → stored in muscles to be sued → excess in adipose tissue around the body

Question 4

Protein

Answer 4

Essential amino acids are found in animal products such as meat, poultry, fish, lentils.
Proteins are broken down into two types of amino acids
essential amino acids - cannot be made by the body, so must be consumed as part of the diet.
non-essential amino acids - can be manufactured from other amino acids in the body
Excess protein: is converted to fats and stored with adipose tissue
Protein function: formation, growth and repair of body tissue and cells and help in the production of red blood cells, hormones and enzymes.
Protein only minimally contributes energy for ATP resynthesis (no more than 5–10%).
In extreme circumstances (starvation or ultra-endurance events 2000-4000km) when the body’s CHO and fat supplies are depleted, protein becomes a source of energy to replenish ATP.
As with fats, protein cannot supply energy at the same rate as carbohydrates.
Starvation or ultra endurance events

Question 5

Energy fuels summary

Answer 5

The fuels or substrates that are used by the body’s three energy systems include creatine phosphate, carbohydrates, fats and protein.
The energy systems break down these fuels to provide the energy to resynthesise ATPCreatine phosphate is a chemical compound which, like ATP, is stored in limited quantities within muscle cells.
Also like ATP, creatine phosphate is a high-energy substance capable of storing and releasing energy via the high-energy bond that binds the creatine and phosphate parts of it together. When this bond is broken, energy is released that enables ATP to be resynthesised from ADP and Pi.
Carbohydrate is broken down into glucose. Glucose is stored as glycogen in the muscles and liver. Any excess is stored as fat in adipose tissue around the body
Fats provide more energy per gram than the other fuels, but the body prefers carbohydrate as an energy source during exercise because it is easier to break down and produces energy at a faster rate. Protein is used as an energy source only when carbohydrate and fats are depleted; for example, in extreme conditions such as in ultra-endurance events.

Question 6

Why the ATP-PC system can provide an athlete energy to perform short high-intensity explosive movements?

Answer 6

The ATP–CP system uses creatine phosphate to create new ATP supplies without using oxygen. The ATP–CP energy system can create ATP very quickly and is the predominant energy contributor to maximal intensity, short-duration activities of up to 6–10 seconds’ duration.
This is because the PC is already stored in the muscles and it requires simple chemical reactions.

Question 7

What is the rate of ATP production of each of the energy systems

Answer 7

AP P-C : very fast
Anerobic glycolysis: Fast
Aerobic: Slow

Question 8

Fuel source of each system?

Answer 8

ATP-PC : Phosphocreatine
Anaerobic glycolysis: Glycogen
Aerobic: carbs and fats

Question 9

Intensity of activity? each system

Answer 9

ATP-PC : high intensity, maximal, 95 max hr plus
Anaerobic : high intensity, maximal, 85-95 max hr plus
Aerobic: submaximal, resing less than 85 and less per cent of max hr

Question 10

Duration of dominance?

Answer 10

Atp;pc: 1-5 secs
Anerobic: 5-60 secs
Aerobic: greater than 75 secs

Question 11

By products each system?

Answer 11

Atp-pc: inorganic phostpahte and ADP
Anaerobic: lactic acid, hydrogen ions, ADP
Aerobic: water, heat carbon dioxide

Question 12

Total duration

Answer 12

ATP:PC: 0-10 secs
Anaerobic:10-2 mins secs
Aerobic: 2 mins plus

Question 13

Fitness components:

Answer 13

Atp:pc : agility, muscular power and dynamic flexibility
anaerobic: muscular endurance, dynamic flexibility and anaerobic power and speed
Aerobic: aerobic capacity/endurance, muscular endurance and static flexibility.

Question 14

Advantages of each system:?

Answer 14

ATP;PC: 
-Resynthesis ATP
immediately
-Used for high intensity
activities
-Doesn’t need long
chemical reactions

Anaerobic:
-Resynthesis ATP
quickly
-Oxygen doesn’t have to be available for anaerobic glycolysis to occur
-Has LIP (the body can prevent the accumulation of hydrogen ions in the working muscles)

Aerobic: 
-Resynthesis large
amounts of ATP
-Produces non-toxic by-
products
-Allows for oxidation of
metabolic by-products and
resynthesis of glycogen
from lactic acid

Question 15

Disadvanatages of each system?

Answer 15

ATP:PC 
-Resynthesises very
limited amounts of ATP
-Limited stores of ATP
and PC in muscle (higher
in fast-twitch fibres)
-Need passive recovery for at least 3 minutes to restore PC
-Doesn’t last very long 

Aneaerobic: 
Produces hydrogen
ions that cause fatigue
in large amounts
-Produces large
amounts of hydrogen
ions that greatly
decreases muscle pH
-Doesn’t last very long 

Aerobic: 
Resynthesises ATP slowly
(particularly fats)
-Fats have a high oxygen
cost resulting in a reduced intensity
-Needs oxygen to occur

Question 16

ATP:PC SYSTEM?

Answer 16

The ATP-PC energy system produces energy by breaking down phosphocreatine (PC) to resynthesise adenosine Triphosphate (ATP). ATP is resynthesised through chemical reactions that do not require oxygen (anaerobic). It is worth noting that all activities that are carried out about 100% VO 2 max depend on an anaerobic energy supply, and if PC has had time to replenish, this will be ‘powered’ by the anaerobic Glycolysis system.
PC, like ATP, is stored in muscle cells and contains phosphate bonds which, when broken, provide large amounts of energy. PC ‘splits’ into Creatine (C) and inorganic phosphate (Pi).
The energy that results from the splitting of the phosphate is linked to the resynthesis of ATP. As rapidly as ATP is broken down by muscular contractions, it is continuously reformed from ADP and Pi (BY-PRODUCTS) by energy released by the breakdown of PC stored in muscle, this is catalysed by the enzyme kinase.

The ATP-PC system does not require oxygen to release energy (anaerobic)
The ATP-PC system provides the fastest rate of ATP release for energy because it depends on simple and short chemical reactions and the ready availability of PC in muscles
The ATP-PC system is anaerobic and so does not depend on oxygen being transported to working muscles to release energy.
A limited amount of PC is stored in the muscles (about 10 seconds worth at maximal intensity), with larger muscles capable of storing slightly more PC than this (12-14 seconds at maximal intensity)
ATP and PC are stored in the muscles and available for immediate energy release. This system is limited by the amount of PC stored in the muscles – the more intense the activity, the quicker this is utilised to produce ATP. After 5 seconds of maximal activity, the anaerobic Glycolysis system becomes the major producer of ATP
Once PC has been depleted in the muscle, ATP must be resynthesised from another substance – typically glycogen, which is stored in the muscles and liver – via anaerobic Glycolysis using the anaerobic Glycolysis system.
The individual must rest for 3-10 minutes, for this system to replenish
This system supports maximal intensity activity (95%) + maximum heart rate). Max heart rate = 220 – age.

Question 17

What is interplay?

Answer 17

At the onset of exercise, all 3 energy systems are activated and are contributing energy. At the beginning of the activity, the ATP-CP system is dominant and is contributing the most amount of energy (100 per cent). As this system depletes the anaerobic energy system takes over and contributes the most amount of energy for approximately 2 minutes. As duration increases the aerobic system will begin to contribute the most amount of energy for the duration of the activity/exercise. Overall the aerobic system will be pre-dominant.

Question 18

Which energy system will provide the centre with the most energy aerobic: from 2 minutes onwards so they game of netball?

Answer 18

The aerobic energy system will provide the most energy to the centre player even though each energy system is contributing energy. The aerobic energy system is contributing the most because the game of netball went for 20 minutes. Anything over two minutes of exercise is where the aerobic energy system produces the most amount of energy. The centre player is working maximally and will reach a steady state. This steady-state was reached in the netball game from 4mintues to ten minutes where the heart rate of the centre varied from 173 - 182. This is where oxygen demand equalled oxygen supply. The centre used more oxygen as she was working at higher intensity also and was doing more running than the goalkeeper. It can be seen that the centre was working at a higher intensity than the GK as the centres highest heart rate for the whole game was 182 bpm whereas the GK highest heart rate was 171. The GK heart also varied more and decreases and increased throughout the game as they stopped starting a lot and therefore using the ATP-PC system which was producing the most amount of energy. The centre player also had little/no period of recovery whereas the GK had time to recover and rest for more time. They were not continuously running/moving.

Question 19

Oxygen deficit:

Answer 19

Temporary shortage of oxygen in cells, typically at the start of exercise where oxygen demands are greater than the body’s ability to supply the necessary levels.
Oxygen demand is greater than oxygen supply.
At the start of the netball match, not once-off oxygen deficit happened every time someone start stops.
Throughout the whole netball, the match centre is continuously running unless on the goal centre.
So goalkeeper has a higher oxygen deficit as they are stop starting more and oxygen deficit occurs every time someone starts and stops.

Question 20

Oxygen debt or EPOC

Answer 20

oxygen debt = recovery o2 intake above resting levels
Why is there an O2 debt immediately after exercise: This is because glucose is not broken down completely to form carbon dioxide and water. Some of it is broken down to form lactic acid.
A deficit of oxygen resulting from intense exercise.
At the completion of the exercise, the demand for ATP decreases dramatically

EPOC
Excess post-exercise oxygen consumption is a measurably increased rate of oxygen intake following strenuous activity.
Also known as oxygen debt, EPOC is the amount of oxygen required to restore your body to its normal, resting level of metabolic function (called homeostasis). It also explains how your body can continue to burn calories long after you’ve finished your workout.

Question 21

steady state?

Answer 21

When Oxygen demand = oxygen supply
Any athlete working maximally will not reach a steady-state
Activity that achieves a balance between the energy required by working muscles and the rate of oxygen uptake and delivery to working muscles for aerobic ATP production. In this state, lactic acid is broken down, removed from the muscles and converted back to its useful form e.g. energy.

Question 22

Oxygen uptake at rest, Exercise and During Recovery

Answer 22

An activity that calls rapidly upon the anaerobic energy systems will have a large oxygen deficit, possibly a brief (or no) steady-state and a large oxygen debt or EPOC.
High-intensity short duration
An activity performed at a lower intensity (aerobic energy system) will have a smaller oxygen deficit, a longer steady-state and a smaller oxygen debt.
Low intensity and long duration
During EPOC, the body uses oxygen to restore muscle glycogen and rebuild muscle proteins damaged during exercise. Even after a High Intensity. Workout is over, the body will continue to use the aerobic energy pathway to replace the ATP consumed during the workout, thus enhancing the EPOC effect.

Question 23

Who will have to the most amount of oxygen deficit?

Answer 23

The GK will have the most amount of oxygen deficit as they stop starting continuously throughout the game. This occurs Temporary shortage of oxygen in cells, typically at the start of exercise so every time[SC1] the GK starts running and then stops and then later starts again. This is where oxygen demands are greater than the body’s ability to supply the necessary levels.The GK is working at a higher intensity.

Question 24

Who will consume the most oxygen?

Answer 24

The centre will consume the most energy as they are continuously running. They are needing more oxygen to get to their working muscles than compared to the GK because they need more energy as they are working more sub-maximally[SC1] and continuously for the netball match. They are playing for the duration of the game. On the other hand, the GK is during short explosive movements stopping and starting more than the centre working more maximally.

Question 25

Who will have the biggest EPOC and why?

Answer 25

EPOC is the amount of oxygen required to restore your body to its normal, resting level of metabolic function (called homeostasis). GK will have the biggest EPOC as they stop starting and every time they start then stop running EPOC occurs. The centre player is continually running and not start stopping as much. They will still have EPOC but it is not as much as the GK.

Question 26

Acute cardiovascular responses to excerise: cardiac output

Answer 26

amount of blood pumped out of the heart in one minute)
Cardiac output is the product of stroke volume (SV), which is the amount of blood pumped out of the left ventricle of the heart per beat, and heart rate (HR), which is the number of times the heartbeat in one minute.

Q (litres per minute)= HR (beats per minute) x SV (litres per beat)
A lower heart rate, together with an increased stroke volume, indicates an efficient circulatory system e.g. higher aerobic fitness. An increase in stroke volume is due to a stronger ventricular contraction causing greater amounts of blood to be ejected.
Heart rate is the most important factor in increasing cardiac output during exercise.

Question 27

Acute cardiovascular responses to excerise: Redistribution of blood flow

Answer 27

During exercise, blood is diverted from the body’s organs to the working muscles so that those muscles receive the greatest percentage of cardiac output.
Vasoconstriction occurs in the arterioles supplying the inactive areas of the body
Vasodilatation occurs in the arterioles supplying the working muscles.

Veins carry de-oxygenated blood back to the heart
Arteries carry oxygen-rich blood away from the heart

Question 28

Acute muscular responses to excerise:

Answer 28

In order for exercise to begin, the muscular contractions responsible for movement
need to increase. The type of contraction, the force and the speed of contraction are
controlled by the central nervous system (CNS).
Increased blood flow:
More blood is delivered to the skeletal muscles during exercise to meet the increased oxygen demands; this is a direct result of the redistribution of blood flow away from the organs to the working muscles. Skeletal capillaries open up (vasodilate) and serve three main purposes.
These are to:
Allow for increases in total muscle blood flow
Deliver large blood volume with minimal increase in blood flow velocity
Increase the surface area to increase diffusion rates

An increase in increased blood flow means more oxygen is delivered to the working muscles.This enables more ATP to be produced aerobically. The more ATP the athlete has the more energy they will have and they won’t fatigue as fast.

Question 29

Lactate

Answer 29

Lactate is a component of Lactic Acid – a by-product of anaerobic Glycolysis. This is produced until oxygen supply meets oxygen demand.
During sub-maximal levels, lactate levels increase rapidly and then tapers off. During maximal activity, Lactate levels will rise and rise, until the body can no longer remove it as fast as it is being produced, at which point the Lactate Inflection Point is reached (LIP).

Question 30

Describe the changes in oxygen demand and supply from rest to submaximal exercise and the relationship between oxygen uptake and exercise intensity.

Answer 30

At rest, energy demand equals energy supply as the body’s oxygen uptake meets all energy requirements.
When exercise begins, oxygen uptake increases as the working muscles use more of the
oxygen made available by the combined efforts of the circulatory and respiratory systems.
There is a linear relationship between oxygen uptake and exercise intensity.
However, from rest to exercise there is a period of time when there is a discrepancy between the amount of oxygen required for a given exercise intensity and the amount actually supplied and used. This is referred to oxygen deficit where there is a shortfall between supply and demand.
For submaximal intensities, it may take only a few seconds for oxygen supply or uptake to meet the demands of the exercise and reach a steady state.

Question 31

LIP?

Answer 31

Lactate inflection point (LIP): The exercise intensity beyond which lactate production exceeds removal, sometimes referred to as the lactate threshold.
LIP = is the last point that lactate entry = lactate removal
The LIP reflects the last point where lactate entry into and removal from the blood are balanced.
It is identified as the final exercise intensity or oxygen uptake value at which blood lactate concentration is relatively stable during a maximal intensity at which blood lactate is in a steady state.

Question 32

How does the distribution of blood flow differ between rest and exercise conditions and explain the mechanisms by which this change occurs?

Answer 32

The distribution of blood flow does differ between rest and exercise conditions. At rest, the distribution of blood flow is mostly at the body organs. When exercising the blood is diverted from the body’s organs to working muscles so that these muscles are receiving the most amount of blood. This means these muscles are receiving more oxygen from the blood which allows more ATP to be produced aerobically. Allowing for the athlete to have more energy and fatigue much later, therefore, improving their performance. Vasoconstriction occurs in the arterioles supplying the inactive areas of the body and vasodilation occurs in the arterioles supplying the working muscles blood.

Question 33

From the data collected, what evidence exists to suggest that the change in heart rate is an acute response to physical activity?

Answer 33

From the data collected, we can see that change in heart rate is an acute response to physical activity as referring to the data as soon as the physical activity started heart rate increased immediately. Subject A’s heart rate went from 77 bpm at rest to 120 after 1 minute. Subjects B’s heart rate went from 60 bpm increasing to 85 bpm after 1 minute of running.

Question 34

15. Why do blood lactate levels remain relatively stable during sub-maximal activity?

Answer 34

Blood lactate remains stable because the body is working submaximally so it has enough time to remove the lactate as it is being produced.

Question 35

In order for the above results to occur, there must be a change in enzyme activity. Explain this change and how it contributes to the use of glycogen.

Answer 35

The process is glycolysis. When we are working maximally the breakdown of glycogen needs to occur faster. In order for this to happen the enzyme activity needs to occur faster as well

Question 36

Increase in cardiac output?

Answer 36

= increase in blood flowing pumped out of the heart in one minute means more oxygen in the body and if there is more oxygen in the body going to the working muscles, my body is able to break down fats and carbs quicker which means the athlete can perform at a high intensity for a longer period of time without getting fatigued.