© Chris Hudd & Edrolo 2018 1
Presented by Chris Hudd
Study design dot points:• oxygen uptake at rest, and during exercise and recovery, including oxygen deficit,
steady state, and excess post-exercise oxygen consumption.
© Chris Hudd & Edrolo 2018 2
Breathe
Source: https://www.youtube.com/watch?v=rmHDhAohJlQ
© Chris Hudd & Edrolo 2018 3
Oxygen uptakeTheory summary
Oxygen uptake, or VO2, represents the volume of oxygen able to be taken up by, transported to,
and used by the body for energy production.
Maximum oxygen uptake, or VO2 max, represents the maximum volume of oxygen able to be
taken up by, transported to, and used by the body for energy production.
Oxygen uptake can be measured as either an Absolute value (L/min), or Relative (ml/kg/min).
Recap:
As exercise
intensity
increases, the
consumption of
oxygen
increases to
allow greater
levels of ATP
production.
Absolute VO2
&
Absolute VO2
max
(L/min)
Relative VO2
&
Relative VO2
max
(ml/kg/min)
© Chris Hudd & Edrolo 2018 4
Oxygen uptake – absolute vs relativeTheory summary
The use of athlete’s relative VO2 allows us to compare aerobic performance.
Lebron James – 113 kg
3.7 km per match
Steph Curry – 86 kg3.9 km per match
Sources (left to right):WikiMedia CommonsFlickr
© Chris Hudd & Edrolo 2018 5
Factors affecting oxygen uptake
Body Size Age
Gender
Genetics Training
© Chris Hudd & Edrolo 2018 6
Oxygen uptake at restTheory summary
At rest, the demand for ATP energy is relatively small. As a result, parameters such as heart rate
and oxygen uptake remain at low levels.
Resting absolute oxygen consumption (VO2) for a 70 kg person is approximately 0.25 L/min.
Resting relative oxygen consumption (VO2) is approximately 3.5 ml/kg/min.
0
0.5
1
1.5
2
2.5
3
0 10 20 30
VO
2(L
/min
)
Time (secs)
VO2 @ rest
O2Demand
Source: https://www.youtube.com/watch?v=YKEOjWEzVGs
© Chris Hudd & Edrolo 2018 7
Theory summary
When exercise begins, oxygen uptake increases as the body attempts to meet the increased
oxygen demand. The increased oxygen demand results from the need to produce more energy for
ATP resynthesis.
Oxygen uptake at start of exercise
Sources (left to right):https://www.youtube.com/watch?v=GKXfpOZqREg
https://www.youtube.com/watch?v=lOAeTfI-Tlc&t=315s
https://www.youtube.com/watch?v=vHU9OFSwmEs
https://www.youtube.com/watch?v=cOK7DvZzo9g
© Chris Hudd & Edrolo 2018 8
Oxygen uptake at start of exercise
EventFemale Average
Speed for WR time (km/h)
400m 30.2
800m 25.4
1500m 23.5
Marathon 18.7
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
VO
2(L
/min
)
© Chris Hudd & Edrolo 2018 9
Theory summary
Oxygen deficit is the period of time at the start of exercise where the oxygen demand exceeds
the oxygen supply.
During oxygen deficit the body must obtain ATP from its anaerobic energy systems.
Oxygen deficit
0
10
20
30
40
50
60
70
80
10 20 30 40 50 60 70 80 90 100 110 120
VO
2(m
l/kg
/min
)
Time (secs)
Oxygen Uptake Oxygen Deficit
© Chris Hudd & Edrolo 2018 10
Theory summary
Steady state is the state in which oxygen supply equals oxygen demand.
At these times, almost all of the required energy for ATP resynthesis is supplied aerobically.
Steady state
0
10
20
30
40
50
60
70
80
10 20 30 40 50 60 70 80 90 100 110 120
VO
2(m
l/kg
/min
)
Time (secs)
Oxygen Uptake Oxygen Deficit
© Chris Hudd & Edrolo 2018 11
Applying these concepts
Source: 2014 VCAA Exam
© Chris Hudd & Edrolo 2018 12
Applying these concepts
Source: 2013 VCAA Exam
© Chris Hudd & Edrolo 2018 13
Theory summary
Aerobic steady state can only be reached once the body has made the required adjustments
(acute responses), to increase oxygen supply.
Important responses include:
• increased respiratory frequency;
• increased tidal volume;
• increased heart rate; and
• increased stroke volume.
Performing an aerobic warm-up will initiate a number of these responses prior to the event and
will reduce the time taken to reach steady state.
Also, chronic adaptations gained through aerobic training will improve an athlete’s aerobic
efficiency, and therefore increase oxygen supply faster.
Reducing time taken to steady state
Source: http://maxpixel.freegreatpicture.com/Stopwatch-Race-Time-Games-Treadmill-Sport-Jogging-259303
© Chris Hudd & Edrolo 2018 14
Theory summary
At the completion of exercise, oxygen consumption remains elevated, despite a reduction in the
demand for ATP energy. This elevated oxygen consumption (EPOC) is also referred to as Oxygen
Debt.
Excess post-exercise oxygen consumption (EPOC)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
30 40 50 60
VO
2 (
L/m
in)
Time (secs)
OxygenDemand
Source: https://www.youtube.com/watch?v=cOK7DvZzo9g
© Chris Hudd & Edrolo 2018 15
Theory summary
EPOC can be further divided into two parts: the first/fast replenishment part; and the
second/slow replenishment part.
Excess post-exercise oxygen consumption (EPOC)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
-1 4 9 14 19
VO
2 (
L/m
in)
Recovery Time (mins)
© Chris Hudd & Edrolo 2018 16
Theory summary
The first 2-3 minutes of recovery is known as the fast replenishment part, and sees the highest
elevation in recovery oxygen consumption.
Recovery processes during the fast replenishment part of EPOC:
Fast replenishment
0
1
2
3
4
5
-1 4 9 14 19
ATP resynthesis
CP resynthesis
Restore oxygen to myoglobin
© Chris Hudd & Edrolo 2018 17
Theory summary
The remaining EPOC is known as the slow component. The recovery time in this part is
dependant on the usage and metabolic disturbances associated with the activity just
performed.
E.g. the higher the intensity and duration of exercise, the greater the accumulation of lactic acid,
and, therefore, the longer the slow replenishment part of EPOC will be.
Recovery processes during the slow replenishment part of EPOC:
Slow replenishment
0
1
2
3
4
5
-1 4 9 14 19
Return core temperature to
pre-exercise levels
Convert lactic acid to 𝑯𝟐𝑶 and
𝑪𝑶𝟐(oxidation of H+ ions)
Convert lactic acid
to glycogen,
protein and glucose
Restore heart rate and
ventilation to pre-exercise
levels
Restore other body systems to
pre-exercise levels
© Chris Hudd & Edrolo 2018 18
Multiple choice activityOn the graph below, the number 1 indicates the period when:
A. oxygen uptake is at resting levels.
B. oxygen supply equals oxygen demand.
C. oxygen supply does not equal oxygen demand.
D. post-exercise oxygen consumption is in excess of resting levels.
E. I don’t know, yet.
(2015 VCAA Exam Section 1 Q6)
© Chris Hudd & Edrolo 2018 19
Multiple choice – ResponseOn the graph below, the number 1 indicates the period when:
A. oxygen uptake is at resting levels.
B. oxygen supply equals oxygen demand.
C. oxygen supply does not equal oxygen demand. (82% correct)
D. post-exercise oxygen consumption is in excess of resting levels.
E. I don’t know, yet.
(2015 VCAA Exam Section 1 Q6)
© Chris Hudd & Edrolo 2018 20
Multiple choice activityWhich of the following strategies would not assist an athlete to reach a steady state faster
whilst competing in a 1500m track event?
A. Run at a faster early pace to reach steady state period
B. Complete an aerobic warm-up prior to the race
C. Complete 15+ weeks of aerobic training in the lead-up to the event
D. Attend a training camp in a hypoxic environment (altitude)
E. I don’t know, yet.
(Written by the author)
© Chris Hudd & Edrolo 2018 21
Multiple choice – ResponseWhich of the following strategies would not assist an athlete to reach a steady state faster
whilst competing in a 1500m track event?
A. Run at a faster early pace to reach steady state period
B. Complete an aerobic warm-up prior to the race
C. Complete 15+ weeks of aerobic training in the lead-up to the event
D. Attend a training camp in a hypoxic environment (altitude)
E. I don’t know, yet.
(Written by the author)
© Chris Hudd & Edrolo 2018 22
Multiple choice activityWhich of the following recovery processes is considered part of the fast component of an
athlete’s oxygen debt?
A. Oxidation of hydrogen ions
B. Restoration of oxygen to myoglobin
C. Return core-temperature to pre-exercise levels
D. Conversion of lactic acid to glycogen
E. I don’t know, yet.
(Written by the author)
© Chris Hudd & Edrolo 2018 23
Multiple choice – ResponseWhich of the following recovery processes is considered part of the fast component of an
athlete’s oxygen debt?
A. Oxidation of hydrogen ions
B. Restoration of oxygen to myoglobin
C. Return core-temperature to pre-exercise levels
D. Conversion of lactic acid to glycogen
E. I don’t know, yet.
(Written by the author)
© Chris Hudd & Edrolo 2018 24
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