Date | May 2019 | Marks available | 4 | Reference code | 19M.2.SL.tz0.5 |
Level | Standard Level | Paper | Paper 2 | Time zone | time zone 0 |
Command term | Explain | Question number | 5 | Adapted from | N/A |
Question
Describe the mechanics of ventilation during high intensity interval training.
Explain different methods of presentation when teaching a skill.
Describe long-term vascular adaptations to endurance training.
Explain how anaerobic energy systems could contribute to ATP production during a 3-minute round of boxing.
Markscheme
Inhalation:
diaphragm contracts and flattens ✔
internal intercostal muscles relax ✔
external intercostal muscles contract ✔
raising the rib cage upwards and outwards ✔
this increases the thoracic volume ✔
this decreases the thoracic pressure ✔
the result of this is that air moves into the lungs ✔
accessory muscles contract such as trapezius / sternocleidomastoids / scaleni ✔
Exhalation:
diaphragm relaxes and moves upwards ✔
internal intercostal muscles contract ✔
external intercostal muscles relax ✔
lowering the rib cage downwards and inwards ✔
this decreases the thoracic volume ✔
this increases the thoracic pressure ✔
the result of this is that air moves out of the lungs ✔
accessory muscles contract such as the abdominal muscles ✔
Mark points must clearly be linked to the relevant process of inhalation or exhalation.
Award [4 max] from inhalation/exhalation.
Award [5 max] if no mention of accessory muscles
The movement of air needs to be clearly linked to the factors of changing volume or pressure or some other relevant variable
[6 max]
Whole
the skill is demonstrated and practised as a whole, from start to finish ✔
commonly used for skills that cannot be easily broken into parts because they are quick and fluent / discrete in nature or simple serial skill ✔
an example would be completing a dig in volleyball / long jump ✔
Whole-part-whole
the whole skill is demonstrated and practised first, before being broken down into its constituent parts and then progressed back to the whole skill ✔
commonly used for complex skills that contain specific parts / serial in nature ✔
an example could be tennis serve by doing the whole action followed by practising the parts «ball toss, arm phases, grip, contact» then putting them together again ✔
Progressive part
parts of the skill are practised individually before being linked together ✔
commonly used for skills that contain discrete parts that form a sequence ✔
an example could be in basketball practising the dribble, then the 2 steps then the jump off one foot before combining ✔
Part
parts of the skill are demonstrated and practised individually ✔
commonly used for complicated or serial skills, where the coach may wish to isolate a particular component to practise ✔
an example could be learning how to do the arm action of a swim stroke using a pull buoy and then the legs using a kick board before putting them together ✔
Explanation must correctly match method for mark.
Award [2 max] for presentation method.
[4 max]
increased capillarisation in lungs/ trained muscles ✔
blood plasma increases ✔
red blood cell count / hemoglobin increases ✔
more effective blood redistribution ✔
these factors result in increased arterio-venous oxygen difference (a-VO2 difference) ✔
decreased resting blood pressure ✔
improved elasticity of blood vessels ✔
decreased resting heart rate ✔
increased stroke volume ✔
lower working heart rate when working at the same intensity as to prior to the training occurred ✔
Lower working HR needs to be clearly linked to when working at the same intensity as prior to training
[4 max]
all systems work concurrently / at all times ✔
dominant system is determined by intensity and duration / the anaerobic system will dominate due to the short duration «3 minutes» and high intensity of many of the actions «punching is explosive» ✔
ATP-CP:
dominant for the first 7–10 seconds ✔
system replenishes initially used ATP ✔
one ATP produced from one CP ✔
has a high rate but low yield ✔
during quieter phases in the round the system may be replenished to assist the seamless flow of ATP ✔
Lactic acid / anaerobic glycolysis:
dominant from five seconds to 1–2 minutes ✔
source of ATP is glucose molecule ✔
2–4 ATP produced from one glucose molecule ✔
bi-product of «hydrogen ions» / lactic acid inhibits effectiveness of ATP production ✔
Award [3 max] per energy system.
Award [5 max] if the explanation does not refer to the energy systems during boxing
[6 max]
Examiners report
Those students that understood they were being asked about mechanics of ventilation generally answered well. However, full marks were rarely awarded as few students mentioned accessory muscles which is a key aspect of the question.
Those students who understood the question answered it well; however, many answered something else. Several referred to ‘teaching styles’ such as command or reciprocal.
This was answered well, with most students able to get 2 marks of the 4 on offer. Most students gave the same two responses (lower stroke volume and resting heart rate). If they had thought deeply about the changes to blood and blood vessels then it should have been possible to gain full marks.
Many candidates did not understand the timeframes, or the exact roles of the different fuel systems, and many seemed confused by the “3-minute” round of boxing. This lead them into a discussion about aerobic sources. Other candidates had no idea (e.g. stating ATP-CP lasts 30 minutes). Many candidates mixed the content up for 5(d) with 3(c), suggesting that candidates did not read the question carefully or understand the main point of the question. Candidates appeared to see "ATP" and wrote all they knew about that topic without considering the actual question.