exercise capacity

Question 1

what are exercise, physical activity and activities of daily living?

Answer 1

exercise - Purposeful, structured activity that involves gross muscular activity to improve physical condition (e.g. jogging, stretching). sorta a subset of physical activity

physical activity - A holistic term that includes all (purposeful and incidental) muscular activity of all intensities (e.g. walking, stairs)

activities of daily living – Basic independent self-care tasks done on a daily basis that require coordination, strength and range of motion

Question 2

what is ventilation perfusion matching?

Answer 2

Efficient gas exchange needs maximum coupling between ventilation and perfusion

v is ventilation
q is perfusion

Inadequacy of either V or Q will have significant impact on removal of CO2 & blood oxygenation

Question 3

what is a cardiopulmonary exercise test?

Answer 3

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

outputs:
Lots and lots of data
Peak VO2 (volume of oxygen consumed, L/min) usually the primary outcome
ECG changes monitored throughout

Question 4

wha tare the advantages and disadvantages of a Cardiopulmonary exercise test?

Answer 4

advantages:
Quantifies performance in relation to metabolism
Precise and reproducible
Continuous monitoring for safety

Disadvantages:
Requires skilled technical support (calibration and
Very expensive (initial & ongoing costs)
Needs dedicated space

Question 5

what is the six minute walk test?

Answer 5

Uses a 20-30 m flat course (e.g. corridor)
Objective is to cover greatest distance as possible in six minutes
Externally timed by assessor
Sub-maximal test

outcomes:
Primary outcome is total distance walked in six minutes
Secondary variables may be ‘perceived exertion’ scales, heart rate and pulse oximetry

Question 6

what are the advantages and disadvantages of the six minute walk test?

Answer 6

Advantages:
Patient-driven pace – speeding up, slowing down & rest OK
Cheap to deploy
Validated in many clinical populations

Disadvantages:
Requires a significant unobstructed course, it often undertaken in a public hospital corridor
The pace is not reregulated

Question 7

what is the incremental shuttle walk test?

Answer 7

Uses a 10 m circuit
Externally paced by an audio recording (like bleep test)
Each minute has one extra length than the previous minute (e.g. minute 1 = 3 lengths of 20s; minute 2 = 4 lengths of 15s)

outputs:
Primary outcome is total distance walked before volitional end
Secondary variables may be ‘perceived exertion’ scales, heart rate and pulse oximetry

Question 8

what are the advantages and disadvantages of the incremental shuttle walk test?

Answer 8

Advantages:
Cheap to deploy
Validated in many clinical populations
The external pacing helps some to achieve maximum levels

Disadvantages:
Requires an unobstructed course, it is often undertaken in a public hospital corridor
For some the incremental nature is difficult (min. speed 1.8km/hour)
Ceiling effect of 1020 m
Patient can be penalised for poor pace management

Question 9

what factors can effect exercise performance?

Answer 9

Neurological (e.g. motor control, coordination)

Respiratory (e.g. ability for lungs to ventilate, for pulmonary perfusion, for gases to exchange between lungs and blood)

Cardiovascular (e.g. ability for heart to receive blood from lungs and to pump to working muscles)

Muscular (e.g. local perfusion, muscle cell enzymes)