Exercise Capacity Flashcards
- Define exercise
2. Give examples
- Purposeful, structured activity
Involves gross muscular activity to improve physical condition
- E.G. jogging, stretching, weight training
- Define physical activity
2. Give examples
- A holistic term that includes all (purposeful
+ incidental) muscular activity of all intensities - E.G. walking, stairs
Define activities of daily living.
Basic independent self-care tasks done on a daily basis that require co-ordination, strength + range of motion
What is needed between ventilation and perfusion for efficient gas exchange?
Maximum coupling is needed between ventilation and perfusion for efficient gas exchange
Maximum coupling is needed between ventilation and perfusion for efficient gas exchange.
Inadequacy of either V or Q will have a significant impact on 2 factors.
What are these 2 factors?
- Removal of CO2
2. Blood oxygenation
Exercise limitation can be caused by deficits in several systems of the body.
Name 2.
E.G.
- Neurological
- Respiratory
- Cardiovascular
- Muscular
Exercise limitation can be caused by deficits in several systems of the body.
One of these systems is the neurological system.
Give an example of a type of deficit that could cause exercise limitation.
E.G. deficits in motor control
E.G. deficits in co-ordination
Exercise limitation can be caused by deficits in several systems of the body.
One of these systems is the respiratory system.
Give an example of a type of deficit that could cause exercise limitation.
E.G. deficits in ability for lungs to ventilate
E.G. deficits affecting pulmonary perfusion
E.G. deficits in gas exchange between lungs + blood
Exercise limitation can be caused by deficits in several systems of the body.
One of these systems is the cardiovascular system.
Give an example of a type of deficit that could cause exercise limitation.
E.G. deficits in ability for heart to receive blood from lungs
E.G. deficits in heart’s ability to pump oxygenated blood to working muscles
Exercise limitation can be caused by deficits in several systems of the body.
One of these systems is the muscular system.
Give an example of a type of deficit that could cause exercise limitation.
E.G. deficits in local perfusion
E.G. defects in muscle cell enzymes
What is cardiopulmonary exercise testing?
A technical, high-precision and relatively expensive way of assessing exercise capacity
What is involved in the cardiopulmonary exercise test?
- Uses a cycle ergometer or treadmill
- Intensity is incremental
- Undertaken under close clinical supervision in a controlled environment
- ECG, ventilation, O2 and CO2 routinely measured
What are the outputs of the cardiopulmonary exercise test?
- Lots of data
- Peak VO2 usually the primary outcome
- ECG changes monitored throughout
Discuss the advantages [3] and disadvantages [3] of the cardiopulmonary exercise test.
Advantages
[+] Quantifies performance in relation to metabolism
[+] Precise + reproducible
[+] Continuous monitoring for safety
Disadvantages
[-] Requires skilled technical support (calibration)
[-] Very expensive (initial + ongoing costs)
[-] Needs dedicated space
Exercise capacity can be evaluated in clinical populations.
Give 3 methods of doing so.
- Cardiopulmonary exercise test
- Six-minute walk test (6MWT)
- Incremental shuttle walk test
What is the six minute walk test (6MWT)?
Way of assessing exercise capacity
Basic protocol that can be undertaken with basic space, kit + personnel
Involves walking over 20-30m flat course and recording distance covered over 6 mins
What does the six minute walk test (6MWT) involve?
- Uses a 20-30m flat course (e.g. a corridor)
- Objective = cover greatest distance possible in 6 mins
- Externally timed by assessor
- Sub-maximal test
What is the primary outcome of the cardiopulmonary exercise test?
Peak VO2 = usual primary outcome
What equipment is used in a cardiopulmonary exercise test?
Cycle ergometer or treadmill
also ECG, equipment for O2/CO2 monitoring
What is the objective of the six minute walk test (6MWT)?
To cover the greatest distance possible in 6 mins
What are the outputs of the six minute walk test (6MWT)?
Primary outcome = total distance walked in 6 mins
Secondary variables may be ‘perceived exertion’ scales, heart rate + pulse oximetry
What is the primary outcome of the six minute walk test (6MWT)?
Primary outcome = total distance walked in 6 mins
What may the secondary variables of the six minute walk test (6MWT) be?
Secondary variables may be ‘perceived exertion’ scales, heart rate + pulse oximetry
What may the secondary variables of the six minute walk test (6MWT) be?
Secondary variables may be ‘perceived exertion’ scales, heart rate + pulse oximetry
Discuss the advantages [3] and disadvantages [2] of the six minute walk test (6MWT).
Advantages
[+] Patient-driven pace - speeding up, slowing down + rest ok
[+] Cheap to deploy
[+] Validated in many clinical populations
Disadvantages
[-] Requires a significant, unobstructed course (but is often undertaken in a public hospital corridor)
[-] The pace is not ‘reregulated’
What is the incremental shuttle walk test?
Way of assessing exercise capacity
Basic protocol that can be undertaken with basic space, kit + personnel
Involves 10m circuit across which a patient must travel - increasing lengths across same interval of time
What does the incremental shuttle walk test involve?
- Uses a 10m circuit
- Externally paced by an audio recording (like bleep test)
- Each minute has one extra length than the previous
E.G. minute 1 = 3 lengths of 20s, minute 2 = 4 lengths of 15s
What distance circuit does the incremental shuttle walk test use?
10m
What distance flat course does the six minute walk test (6MWT) use?
20-30m
What are the outputs of the incremental shuttle walk test?
Primary outcome = total distance walked before volitional end
Secondary variables may be ‘perceived exertion’ scales, heart rate + pulse oximetry
What is the primary outcome of the incremental shuttle walk test?
Primary outcome = total distance walked before volitional end
What may the secondary variables of the incremental shuttle walk test be?
Secondary variables may be ‘perceived exertion’ scales, heart rate + pulse oximetry
Discuss the advantages [3] and disadvantages [4] of the incremental shuttle walk test.
Advantages
[+] Cheap to deploy
[+] Validated in many clinical populations
[+] The external pacing helps some to achieve maximum levels
Disadvantages
[-] Requires an unobstructed course (but is often undertaken in a public hospital corridor)
[-] For some, the incremental nature is difficult (min. speed 1.8km/hr)
[-] Ceiling effect of 1020m
[-] Patient can be penalised for poor pace management
What does the acronym “IC” stand for?
Inspiratory capacity
the max. volume of air that can be inspired after reaching end of a normal quiet expiration
What does the acronym “MVV” stand for?
Maximal voluntary ventilation
aka maximal breathing capacity - max. minute volume of ventilation that they can maintain for 12-15s
What is the oxygen pulse?
VO2/heart rate
= ratio of O2 consumption:heart rate
= (v) of O2 ejected from ventricles with each heart beat
What does the acronym “PETCO2” stand for?
End-tidal carbon dioxide partial pressure
Used to track PaCO2 in the arteries
What does the acronym “PETO2” stand for?
End-tidal oxygen partial pressure
Refers to PO2 of exhaled gas
What does the acronym “SBP” stand for?
Systolic blood pressure
What does the acronym “SpO2” stand for?
Peripheral oxygen saturation
Measure of Hb carrying O2 in blood relative to amount of Hb not carrying O2
What can exercise tests be used to monitor?
Inc.
- Disease severity
- Disease progression
- Response to treatment
How can supplemental oxygen impact:
a) exercise capacity?
b) breathlessness?
a) can improve exercise capacity
b) can help relieve breathlessness BUT doesn’t always do so
How is the output of a CPET/CPEX often represented?
In a nine-panel chart
This chart details the relationship between key measured + derived variables
In athletic populations, what 2 values is it especially useful to determine?
- Maximal or peak cardiopulmonary performance
- Anaerobic threshold
