Exercise Capacity

Question 1

What is exercise?

Answer 1

purposeful, structured activity that involves gross muscular activity to improve physical condition

Question 2

What is physical activity?

Answer 2

a holistic term that includes all (purposeful and incidental) muscular activity of all intensities.

Question 3

What are activities of daily living?

Answer 3

basic independent self-care tasks done on a daily basis that require co-ordination, strength and range of motion

Question 4

What happens if there is a deficiency in either ventilation or perfusion?

Answer 4

a significant impact on CO2 removal and blood oxygenation

Question 5

How do you evaluate exercise capacity in clinical populations?

Answer 5

• cardiopulmonary exercise test
• 6 minute walk test
• incremental shuttle walk test

Question 6

What is involved in a cardiopulmonary exercise test?

Answer 6

• use a cycle ergometer or treadmill
• under close clinical supervision in a controlled environment
• ECG, ventilation, O2 and CO2 routinely measured

Question 7

What are the outputs of a cardiopulmonary exercise test?

Answer 7

• ECG changes monitored throughout

- peak VO2 (usually primary outcome)

Question 8

What are the advantages of doing a cardiopulmonary exercise test?

Answer 8

• quantifies performance in relation to metabolism
• precise and reproducible
• continuous monitoring for safety

Question 9

What are the disadvantages of doing a cardiopulmonary exercise test?

Answer 9

• requires skilled technical support (calibration)
• very expensive (both initial and ongoing costs)
• needs a dedicated space

Question 10

What is involved in a 6 minute walk test?

Answer 10

• uses a 20-30m flat course
• aim: cover the greatest distance as possible in 6 minutes
• externally timed by assessor
• sub-maximal test

Question 11

What are the outputs of a 6-minute walk test?

Answer 11

• total distance walked in 6 minutes (primary outcome)

- perceived exertion scales, heart rate and pulse oximetry

Question 12

What are the advantages of doing a 6-minute walk test?

Answer 12

• patient-driven pace (speeding up, slowing down and rest is ok)
• cheap to deploy
• validated in many populations

Question 13

What are the disadvantages of doing a 6-minute walk test?

Answer 13

• requires a significant, unobstructed course - often a corridor
• unregulated location

Question 14

What is involved in an incremental shuttle walk test?

Answer 14

• uses a 10m circut
• externally paced by an audio recording (like a bleep test)
• each minute has one extra length than the previous one

Question 15

What are the outputs of an incremental shuttle walk test?

Answer 15

• total distance walked before volitional end (primary)

- percieved exertion scales, heart rate, pulse oximetry

Question 16

What are the advantages of doing an incremental shuttle walk test?

Answer 16

• cheap to deploy
• validated in many populations
• external pacing helps to achieve maximum levels

Question 17

What are the disadvantages of doing an incremental shuttle walk test?

Answer 17

• requires an unobstructed course
• often done in corridor
• for some the incremental nature is difficult
• ceiling effect of 1020m
• patient can be penalised for poor pace management

Question 18

Which systems in which failure can lead to reduced exercise capacity?

Answer 18

• neurological
• respiratory
• cardiovascular
• muscular

Question 19

How can neurological deficits lead to a reduced exercise capacity?

Answer 19

• motor control

- co-ordination

Question 20

How can respiratory deficits lead to a reduced exercise capacity?

Answer 20

• ability of ventilation
• pulmonary perfusion
• gas exchange

Question 21

How can muscular deficits lead to a reduced exercise capacity?

Answer 21

• local perfusion

- muscle cell enzymes

Question 22

What are exercise tests used for?

Answer 22

to monitor disease severity/progression and response to treatment

Question 23

What is the impact of supplemental oxygen on exercise capacity?

Answer 23

can improve exercise capacity

- doesn’t always relieve breathlessness

Question 24

How is the output of a CPET/CPEX represented?

Answer 24

• nine-panel chart

- relationship between key measured and derived variables