Year 12 Phys Ed – Energy Systems
Practice Questions
Multi Choice – Question 1
• Select the most likely cause of fatigue in
performance as many push ups as possible in
10 seconds?
A) Local muscle glycogen depletion
B) H+ accumulation
C) PC depletion
D) None of the above
Question Two
• The accumulation of ADP has been
investigated as a potential source of muscular
fatigue. This is most likely to occur when
predominately using the following energy
system;a) Aerobic system
b) ATP-PC system
c) Anaerobic System
d) ADP-PC system
Question Three
• The lactate inflection point is best described as
occurring when;
a) Oxygen consumption meets oxygen supply and
OBLA occurs
b) Ventilation decreases in an effort to prevent
large amounts of CO2 from accumulating
c) Athlete’s reach 85% VO2 Max
d) Lactic acid accumulates at a greater rate than
which it can be oxidized and prevented from
accumulating
Question 4
• Most of the PC depleted during Physical
Activity will be re-synthesised during;
a) The first 3 mins of a passive recovery
b) The ‘fast part’ of EPOC
c) The first 30 mins when post exercise creatine
monohydrate is consumed
d) All of the above
Short Answer – Question 1
• Most athletes undertake the 20 mtr shuttle
run (beep test) to assess their aerobic capacity
at various stages of the training year.
• Recently a CD was released that allows
athletes to run at Level 6, 8 or 10 without any
increases in workload for 5 mins.
a) List the predominant fuel sources and energy
system for the following stages of the test.
•
•
•
•
Waiting for the test to begin
Jogging the first 20 m
Jogging between cones during Level 6
Sprinting between cones after missing 1 beep
at Level 11
• Jogging between cones during Level 12
10 marks
Describe the energy system interplay likely to occur for
a person capable of reaching Level 12 during;-
• A) The first minute of the test
8 marks
• B) the last minute of the test
8 marks
Question Two
• What is the ‘extra’ oxygen taken in after the
event has been finished used for in terms of
assisting recovery?
3 marks
Question Three
• Is it actually possible for athletes to perform at
110% VO2 max?
• Briefly discuss how this is possible by making
reference to the energy system(s) used.
• 3 marks
Question Four
• During a series of short sprints (4x 20 mtr
sprints with 2 mins rest) both anaerobic
energy systems are used (ATP-PC and Lactic
Acid).
• What is the most likely fatigue causing factor
and explain how this would occur.
• 2 marks
Answers
•
•
•
•
•
Multi-choice:
Qn 1 – C
Qn 2 – B
Qn 3 – D
Qn 4 - A
Answers – short answer qn’s
Qn 1
• Waiting for the test to begin – Aerobic/Fats
• Jogging the first 20 m- ATP-PC /CP
• Jogging between cones during Level 6 –
Aerobic/Glycogen (CHO)
• Sprinting between cones after missing 1 beep at
Level 11 – Lactic Acid/Glycogen (CHO)
• Jogging between cones during Level 12Aerobic/Glycogen (CHO)
Qn 2- The first minute of the test
• All three energy systems start contributing to
ATP production with the first step, with most
coming from the ATP-PC system. The test is
‘slow paced’ to begin with so PC stores will
not be depleted at the same rate as if they
were being called upon for maximum activity
and hence contribution to ATP production will
last approximately 15 seconds. .....
.....The LA system increases its contribution to
energy production as the test continues but
doesn’t really come into play a great deal
during the first minute. Most of the ATP is
provided by the aerobic system due to the
plentiful supplies of oxygen and the low
intensity/demands for oxygen.
Answer: extra oxygen-Where??
•
•
•
•
•
•
Resynthesise ATP and PC
Removing H+ ions
Restore oxygen to the muscles
Converts LA back to glycogen
Restores body temperature
Supplies o2 to the cardiovascular and
respiratory systems
During last minute of the test
• At level 12 the pace is quite fast and the PC
stores would have essentially been depleted
without any chance to be restored. The LA
system would have increased its contribution
to ATP production as the demand for oxygen
exceeds the supply, but at this stage of the
test the aerobic system would be the major
ATP provider, even if the athlete is sprinting.
• Why?
• The aerobic system is capable of
producing 20-30 times more ATP
than both anaerobic systems
combined and would have more
than sufficient time to be
activated.
110% VO2 max – how?
• This occurs when energy is being supplied
anaerobically, usually with aid of the lactic
acid system. Due to the fact that oxygen
required does not meet oxygen demand and
needs to call upon another system to help
supply the energy that’s needed.
Fatigue causing factor
• Due to the fact that subject used the LA
system predominantly there would be a buildup of;• Metabolic By-products.
• The build up of H+ ions when working in the
LA system because the body can’t break them
down. Muscles will stop functioning to the
best of their ability with the build up of H+
ions.
SAC tips....
• Take a highlighter and underline/highlight any
important KEY WORDS in the question.
• Does question ask you for energy system, fuel
source – read question carefully.
• Try to put more info into your answers –
better more than less.
• Marks allocated generally = amount of points
need to be made...more is better!
• Use all your 100 mins.
• Write notes on a piece of
paper before converting it to
your final SAC paper.
• Re-read over your answers and
check that you haven’t missed
out on anything.