Physical Education [3/4] Question Thread

[JemRayment]

Hi,

I am having no trouble learning the content but when it comes to SACs, my answers are always really detailed and long. Is there any technique you have that I can do so my answers are more succinct? Are dot points suitable? Also, what would be the best way in answering a question that involves energy system interplay and O2 deficit, steady state and O2 debt for an endurance athlete. The question was worth 6 marks on my SAC. Thanks!!

[gisele]

Hi,

I am having no trouble learning the content but when it comes to SACs, my answers are always really detailed and long. Is there any technique you have that I can do so my answers are more succinct? Are dot points suitable? Also, what would be the best way in answering a question that involves energy system interplay and O2 deficit, steady state and O2 debt for an endurance athlete. The question was worth 6 marks on my SAC. Thanks!!

Hey JemRayment! I had the same issue at the start of year 12 (and only partly broke out of it tbh ). I would advise against using dot points. Practice makes perfect with things like this. My advice would be to take one of your long, detailed responses and re-write it more concisely/precisely. Firstly identify what the specific issue is. If you feel like you're being too repetitive, then omit some of the redundant words/phrases. If you feel like you're doing a lot of summing-up, then omit those 'summary' sentences. If you're taking 2 lines to explain something that could be explained in half a line, then consider the key PE words like "vasoconstriction" rather than "the narrowing of blood vessels" or "active muscles" rather than "the muscles in the body that are currently working". Or if you're just being too detailed... I mean, that's good in a way because it's better to ensure that you absolutely get full marks rather than just writing the bare minimum. But if you're overdoing it and taking up too much of SAC time, definitely try one of the above options.

When responding to the energy system interplay questions...
FIRST SENTENCE YOU WANT TO WRITE 100% OF THE TIME: "At the beginning of (the event) all three energy systems are activated and contribute to ATP resynthesis." This will get you [1 mark] straight away.
Now you're expected to outline O2 deficit [1 mark], steady state [1 mark] and O2 debt [1 mark], we have covered 4 out of 6 marks. How do you get the other 2 marks? Talk about the predominant system at each time period and it's important to explain why they are the dominant one.

How I'd go about this: (in brief dot points - you should be writing full sentences)
- "At the beginning of the endurance event, all three energy systems are activated and contribute to ATP resynthesis." [1 mark]
- start with ATP-PC since it is immediately available [1 mark]
- PC depletes --> anaerobic glycolysis because we are still in O2 deficit [1 mark]
- after a while O2 supply = O2 demand hence 'steady state' [1 mark]
- aerobic glycolysis takes over as predominant E.S. from this stage onwards [1 mark]
- end of event - O2 debt occurs to 'pay back' the O2 deficit from before [1 mark]
= 6 marks total. DONE

* note: with E.S. interplay questions, you should also have a sentence at the end outlining what the OVERALL dominant E.S. is for the event and why (in this case the aerobic glycolysis, because of the sub-max intensity & long duration (endurance)).

Hope this helps 

[howey]

When responding to the energy system interplay questions...
FIRST SENTENCE YOU WANT TO WRITE 100% OF THE TIME: "At the beginning of (the event) all three energy systems are activated and contribute to ATP resynthesis." This will get you [1 mark] straight away.

Great advice, I always wrote nearly exactly the same thing for my first sentence every single time . Will get you one mark straight away!

[JemRayment]

Hi Gisele,

Thank you for your reply! Your advice is really helpful and I'm glad I'm not the only one who faced this problem

[lillianmaher]

Hello,
Does anybody have any resources for the Games Analysis Sac for Netball? For example how to explain the importance of fitness components in netball (like templates)? Or any other resources for games analysis related to Netball? Would be much appreciated! Please and thank you!

[anotherworld2b]

Hi I am a WACE student and was hoping if I could have some help.
My teacher gave us questions to answer in regards to a experiment on heart rate.
It involved a person jogging at a steady pace for 400 m with their heart rate being recorded at each interval of 100 m. (100, 200, 300 and 400m)
The graph for this experiment showed the subject's heart rate increased dramatically from 0m to 100m but only gradually each time for 100- 200, 200 -300 and 300- 400m.
I tried to explain why heart rate would only gradually increase from 200m to 400m and was wondering if someone could tell me if my explanation would be correct.

Spoiler

slowly repaid.

[howey]

Hi I am a WACE student and was hoping if I could have some help.
My teacher gave us questions to answer in regards to a experiment on heart rate.
It involved a person jogging at a steady pace for 400 m with their heart rate being recorded at each interval of 100 m. (100, 200, 300 and 400m)
The graph for this experiment showed the subject's heart rate increased dramatically from 0m to 100m but only gradually each time for 100- 200, 200 -300 and 300- 400m.
I tried to explain why heart rate would only gradually increase from 200m to 400m and was wondering if someone could tell me if my explanation would be correct.

Spoiler

Initially anaerobic respiration allows cells to produce some energy in the absence of oxygen from glucose. This resulted in the accumulation of lactic acid in the muscles and an oxygen debt from combining lactic acid with oxygen to form glucose and eventually glycogen. Heart rate continues to increase as the subject deplete their anaerobic sources of energy and starts to switch to aerobic energy production from 200 metres to 400 metres. As the subject’s speed and activity intensity remains the same from 200 metres onwards, the amount of oxygen required for the activity remains the same. This meant a sharp increase in heart rate was not necessary to maintain a steady jog. Heart rate and stroke volume is a key determinant of how much oxygen can be delivered to the working muscles. To provide sufficient oxygen necessary for aerobic respiration to maintain muscle activity and to ensure that blood supply to the muscles is adequate, heart rate will increase gradually from 200 metres onwards. The increased heart rate allows lactic acid to be carried away by the blood to the liver, where it is broken down. It also allows the oxygen debt incurred by the body to be slowly repaid.

Good question! First of all, I should just say I know nothing about the WACE study design or expected answers, so I can only answer this from a VCE point of view.

You're on the right track. My key points in this answer would be:
- At the start of exercise oxygen deficit would occur as the body's cardiovascular and respiratory systems respond to physical activity (you've said oxygen debt - I know in VCE oxygen debt only occurs at the end of exercise, oxygen deficit occurs at the start)
- Once the athlete has hit the 100m mark (or 200m mark, if you're only talking about that in your answer), oxygen supply is very close to equalling oxygen demand, as the exercise intensity is constant
- Therefore, the athlete's heart rate will remain fairly steady, as they don't need to take in any more oxygen as the intensity is constant

Note: If the athlete were to have a completely steady HR, you could talk about how they have entered steady state - where oxygen supply equals oxygen demand.

I hope this helps!!

[anotherworld2b]

Would a oxygen deficit also be due to anaerobic respiration at 0m to 100m?
So basically once the athlete has hits the 100m mark and onwards, oxygen supply is very close to equalling oxygen demand, as the exercise intensity is constant. Therefore, the athlete's heart rate will remain fairly steady, as they don't need to take in any more oxygen as the intensity is constant
But How would you explain why heart rate would still increase from 200m to 400m but to a lesser degree? is it due to the oxygen deficit?

Good question! First of all, I should just say I know nothing about the WACE study design or expected answers, so I can only answer this from a VCE point of view.

You're on the right track. My key points in this answer would be:
- At the start of exercise oxygen deficit would occur as the body's cardiovascular and respiratory systems respond to physical activity (you've said oxygen debt - I know in VCE oxygen debt only occurs at the end of exercise, oxygen deficit occurs at the start)
- Once the athlete has hit the 100m mark (or 200m mark, if you're only talking about that in your answer), oxygen supply is very close to equalling oxygen demand, as the exercise intensity is constant
- Therefore, the athlete's heart rate will remain fairly steady, as they don't need to take in any more oxygen as the intensity is constant

Note: If the athlete were to have a completely steady HR, you could talk about how they have entered steady state - where oxygen supply equals oxygen demand.

I hope this helps!!

[howey]

Would a oxygen deficit also be due to anaerobic respiration at 0m to 100m?
So basically once the athlete has hits the 100m mark and onwards, oxygen supply is very close to equalling oxygen demand, as the exercise intensity is constant. Therefore, the athlete's heart rate will remain fairly steady, as they don't need to take in any more oxygen as the intensity is constant
But How would you explain why heart rate would still increase from 200m to 400m but to a lesser degree? is it due to the oxygen deficit?

Yes, the oxygen deficit from 0 to 100m would be because the anaerobic energy systems are producing the majority of the ATP.
The slight increase is interesting - usually in these type of questions HR remains constant after a certain point (e.g. 200m). Heart rate would increase because there is a greater demand for oxygen than is currently being supplied. Usually, this is because exercise intensity increases. In this case, there may just be a slight increase because the athlete hasn't quite settled into steady state yet - so yes, there would be a small oxygen deficit because the anaerobic energy systems are still providing a small amount of the energy from 200m-400m, and their contribution is slowly decreasing (hence the slowly increase in HR as the aerobic system provides more of the energy).

[anotherworld2b]

Does that mean that oxygen deficit would be occurring throughout the exercise? (0m to 400m)
Wouldn't aerobic respiration begin from 200 metres and onwards? Would oxygen deficit still be present?

Yes, the oxygen deficit from 0 to 100m would be because the anaerobic energy systems are producing the majority of the ATP.
The slight increase is interesting - usually in these type of questions HR remains constant after a certain point (e.g. 200m). Heart rate would increase because there is a greater demand for oxygen than is currently being supplied. Usually, this is because exercise intensity increases. In this case, there may just be a slight increase because the athlete hasn't quite settled into steady state yet - so yes, there would be a small oxygen deficit because the anaerobic energy systems are still providing a small amount of the energy from 200m-400m, and their contribution is slowly decreasing (hence the slowly increase in HR as the aerobic system provides more of the energy).

[howey]

Does that mean that oxygen deficit would be occurring throughout the exercise? (0m to 400m)
Wouldn't aerobic respiration begin from 200 metres and onwards? Would oxygen deficit still be present?

Technically, yes, oxygen deficit would be occurring throughout the entire 400m - although it would be very minimal in the last 300m compared to the first 100m. While HR is still increasing, however, and exercise intensity is staying the same, then the anaerobic energy systems must be producing some of the energy - hence there is oxygen deficit (as the definition of oxygen deficit is how much extra oxygen would be needed for the exercise to be performed aerobically).

Aerobic respiration would be present throughout the entire 400m, it would just be less dominant towards the beginning of the exercise (e.g. the first 100m) as the aerobic energy system takes some time to 'warm up'.

[anotherworld2b]

Thank you for your help
Would it be okay if I post a complete explanation about 20 mins from now and ask for you to have a read of it please?

Technically, yes, oxygen deficit would be occurring throughout the entire 400m - although it would be very minimal in the last 300m compared to the first 100m. While HR is still increasing, however, and exercise intensity is staying the same, then the anaerobic energy systems must be producing some of the energy - hence there is oxygen deficit (as the definition of oxygen deficit is how much extra oxygen would be needed for the exercise to be performed aerobically).

Aerobic respiration would be present throughout the entire 400m, it would just be less dominant towards the beginning of the exercise (e.g. the first 100m) as the aerobic energy system takes some time to 'warm up'.

[anotherworld2b]

Here's my full explanation. Can i ask for some help in cutting down parts i don't need and advice on things I've missed?
All the help provided is greatly appreciated 

Spoiler

The data collected indicated as the amount of exercise increases, heart rate will increase gradually until a max heart rate is reached. When a person is about to begin exercising, there is an anticipatory response brought about by the autonomic nervous system and by release of the hormone adrenaline, heart rate and stroke volume increases. At the start of exercise oxygen deficit would occur as the body's cardiovascular and respiratory systems respond to physical activity. The oxygen deficit from 0 to 100m would be because the anaerobic energy systems are producing the majority of the ATP. This is because to maintain the activity of the muscle cells during exercise a source of energy is required. Aerobic respiration would be present throughout the entire 400m, it would just be less dominant towards the beginning of the exercise (e.g. the first 100m) as the aerobic energy system takes some time to 'warm up'. In the experiment the subject’s sudden increase in activity intensity by moving from standing to starting a steady jog reflected the corresponding initial sharp increase in heart rate shown in the graph from 0 metres to 100 metres. As the body’s initial demand for oxygen and nutrients was significantly greater at the start of the experiment a sharp increase in heart rate was necessary in order to increase blood flow and stroke volume in response to the subject’s sudden increase in activity intensity. In order to maintain the activity of the muscle cells. A large increase in blood flow was required to ensure an adequate supply of oxygen and nutrients, and to remove the carbon dioxide and heat produced. This meant the cardiac output and stroke volume would increase as the rate of blood flow depends on how fast the heart is beating and how much blood the heart pumps with each beat.

Initially anaerobic respiration allows cells to produce some energy in the absence of oxygen from glucose. This resulted in the accumulation of lactic acid in the muscles and an oxygen debt from combining lactic acid with oxygen to form glucose and eventually glycogen. Once the athlete has hit the 100m mark and onwards, oxygen supply is very close to equalling oxygen demand, as the exercise intensity is constant. Therefore, the athlete's heart rate will remain fairly steady, as they don't need to take in any more oxygen as the intensity is constant. Heart rate continues to increase as the subject deplete their anaerobic sources of energy and starts to switch to aerobic energy production from 200 metres to 400 metres. As the subject’s speed and activity intensity remains the same from 200 metres onwards, the amount of oxygen required for the activity remains the same. This meant a sharp increase in heart rate was not necessary to maintain a steady jog.  Heart rate would increase because there is a greater demand for oxygen than is currently being supplied. In this case, there may just be a slight increase because the athlete hasn't quite settled into steady state yet - so yes, there would be a small oxygen deficit because the anaerobic energy systems are still providing a small amount of the energy from 200m-400m, and their contribution is slowly decreasing (hence the slowly increase in HR as the aerobic system provides more of the energy). Oxygen deficit would be occurring throughout the entire 400m - although it would be very minimal in the last 300m compared to the first 100m. While HR is still increasing, however, and exercise intensity is staying the same, then the anaerobic energy systems must be producing some of the energy - hence there is oxygen deficit (as the definition of oxygen deficit is how much extra oxygen would be needed for the exercise to be performed aerobically). Heart rate and stroke volume is a key determinant of how much oxygen can be delivered to the working muscles. To provide sufficient oxygen necessary for aerobic respiration to maintain muscle activity and to ensure that blood supply to the muscles is adequate, heart rate will increase gradually from 200 metres onwards. The increased heart rate allows lactic acid to be carried away by the blood to the liver, where it is broken down. It also allows the oxygen debt incurred by the body to be slowly repaid.

[howey]

Can I ask how many marks the question is worth, anotherworld2b?

[howey]

Okay, I've gone through and edited/slightly rewritten your response, anotherworld2b (I've tried to leave it in your words as much as possible). I should add that this is a very in-depth response (e.g. a 6 or 8-mark question). Hopefully it all makes sense.

Spoiler

The data collected indicated as the amount of exercise increases, heart rate will increase gradually until a max heart rate is reached. At the start of exercise, oxygen deficit would occur as the body's cardiovascular and respiratory systems respond to physical activity. The oxygen deficit from 0 to 100m would be because the anaerobic energy systems are producing the majority of the ATP. Aerobic respiration would be present throughout the entire 400m. At the beginning of exercise (e.g. the first 100m), it would be less dominant as the aerobic energy system takes some time to function at full capacity. In the experiment, the participant’s sudden increase in activity intensity by moving from standing to a steady jog reflected the corresponding initial sharp increase in heart rate shown in the graph from 0-100 metres. As the body’s initial demand for oxygen and nutrients increased significantly at the start of exercise, a sharp increase in heart rate was necessary in order to increase blood flow and stroke volume, which supplies oxygen and nutrients to the muscles and removes waste products.

Initially, anaerobic respiration allows ATP to be produced in the absence of oxygen. This results in the accumulation of lactic acid and other fatigue-causing by-products, such as H+ ions, in the muscles. After the 100m mark, oxygen supply is very close to equalling oxygen demand, as the exercise intensity is constant. Therefore, the athlete's heart rate will remain fairly steady, as they don't need to take in any more oxygen. Heart rate continues to increase slightly as the participant depletes their anaerobic sources of energy and the aerobic energy system becomes more predominant from 200-400m. Heart rate may slightly increase because the athlete hasn’t quite settled into steady state, and there is a slightly greater demand for oxygen than is currently being supplied. This increased heart rate will also allow for fatigue-causing by-products produced by the anaerobic energy systems to be removed.

I'm glad I've been able to help you