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Date November 2019 Marks available 5 Reference code 19N.2.HL:.tz0.5
Level Higher Level Paper Paper 2 Time zone time zone 0
Command term Explain Question number 5 Adapted from N/A

Question

Distinguish between health-related and performance-related fitness.

[1]
a.i.

Apply two health-related components of fitness to a marathon runner.

[2]
a.ii.

Describe the exchange of carbon dioxide from the bloodstream during exercise.

[4]
b.

Explain the reason for elevated breathing in the first minutes after a swimming sprint.

[5]
c.

Outline two types of drag that can occur in swimming.

[4]
d.i.

Suggest how a triathlete (swimming, cycling, running) can overcome drag.

[4]
d.ii.

Markscheme

performance-related fitness is based on attributes such as agility/balance/coordination/power/reaction time/speed, whereas health-related fitness is related to body composition/cardio-respiratory fitness (aerobic capacity)/flexibility/muscular endurance/strength ✔

a.i.

Aerobic capacity:
capacity of the runner to take in, transport and use oxygen system to sustain movement or effort over a period of time ✔

Muscular endurance:
the capacity of legs to repeat movements over a period of time without undue fatigue ✔

Body composition:
a low percentage of fat reduces amount of work required by leg muscles ✔

Flexibility:
can increase stride length ✔

Strength:
enables athlete to maintain speed up hill ✔

Accept other acceptable examples of application to a marathon runner.

a.ii.

there are increasing levels of CO2 during exercise ✔

diffusion gradient / rate of exchange is increased ✔

gases move from an area of high concentration to an area of low concentration ✔

CO2 is carried in the blood as bicarbonate (ions) dissolved in plasma (bound to hemoglobin)
OR
CO2 is carried in the form of bicarbonate ✔

CO2 <dissolved in plasma> diffuses from <pulmonary> capillaries into the alveoli and exhaled ✔

(when blood enters the lungs) carbonic acid dissociates into CO2 and H2O ✔

CO2 is released from hemoglobin (carbaminohemoglobin) in the lungs and into the alveoli and exhaled ✔

b.

the greater the intensity of the exercise, the greater the EPOC ✔

initial stages of exercise, oxygen demand cannot be met by the aerobic system <oxygen deficit>
OR
initial stages are met by anaerobic processes ✔

oxygen deficit is paid back after exercise/oxygen debt ✔

alactic/fast component is replenished with <3–4 litres of> oxygen ✔

ATP and CP/PC stores are replenished ✔

myoglobin oxygen levels are replenished ✔

aerobically metabolize lactic acid ✔

resynthesize lactate to glycogen ✔

replacement of muscle / liver glycogen stores ✔

c.

Surface drag:
<sum of> friction forces between fluid molecules and the object. ✔

as a body moves through a fluid, its outer surface catches a layer of the fluid nearby, slowing it down ✔

this can be minimized by changing the surface to reduce the interaction between surface and fluid ✔

Form drag:
as a body pushes against a fluid, the fluid pushes back (action and reaction) ✔

the greater the surface area the greater the drag ✔

Wave drag:
acts where there is a reaction between two types of fluids ✔

when a body moves along the surface of a fluid, some fluid is displaced to form a wave that can oppose motion ✔

d.i.

by wearing closer-fitting, smoothing clothing/head gear ✔

through shaving down body hair ✔

swimming underwater as much as possible ✔

swimming in a deck level pool/ using specialized wave limiting lane ropes✔

streamlining their body position ✔

use of drafting behind another swimmer/cyclist ✔

modifications to bicycle to make it more aerodynamic ✔

d.ii.

Examiners report

[N/A]
a.i.
[N/A]
a.ii.
[N/A]
b.
[N/A]
c.
[N/A]
d.i.
[N/A]
d.ii.

Syllabus sections

Topic 3: Energy systems » 3.3. Nutrition and energy systems » 3.3.8. Explain the phenomena of oxygen deficit and oxygen debt.
Topic 3: Energy systems » 3.3. Nutrition and energy systems
Topic 3: Energy systems

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