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

• peak VO2 (usually primary outcome)
• ECG changes monitored throughout

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 pace

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 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

Question 25

What is a common disease which can impair exercise capacity?

Answer 25

COPD

Question 26

What is an additional use of measuring exercise capacity?

Answer 26

determine maximal or peak cardiopulmonary performance and anaerobic thresold (useful for athletes)