Evaluating Exercise Capacity Flashcards
define exercise
Purposeful, structured activity that involves gross muscular activity to improve physical condition (e.g. jogging, stretching)
define physical activity
A holistic term that includes all (purposeful and 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 coordination, strength and range of motion
list examples of pathophysiologies that impact exercise capacity
restrictive lung disease e.g. asthma
SA node dysfunction, complete AV block, cardiomyopathy, aortic stenosis, bronchospasm
list factors affecting exercise capacity (breathing)
inspired O2
airway calibre
diffusion distance
pulmonary compliance and elastence
list factors affecting exercise capacity (blood)
MCH RBC count Hb pulmonary perfusion venous return arterial blood pressure blood viscosity
list factors affecting exercise capacity (heart)
valve structure myocardial contractility myocardial thickness myocardial perfusion conduction system
list factors affecting exercise capacity (periphery)
capillary density mitochondrial density local vasodilation perfusion of the digestive system oxidative enzyme concentration
list three test that can be used to evaluate exercise capacity
cardiopulmonary exercise test
six-minute walk test
incremental shuttle walk test
what is involved in a cardiopulmonary exercise test?
Uses a cycle ergometer or treadmill, intensity is incremental, under close clinical supervision in controlled environment
what is routinely measured in the cardiopulmonary test?
ECG, ventilation, O2 and CO2 routinely measured
what is the primary outcome of the cardiopulmonary test?
peak VO2
ECG changes
list advantages of the cardiopulmonary test
Quantifies performance in relation to metabolism
Precise and reproducible
Continuous monitoring for safety
list disadvantages of the cardiopulmonary test
Requires skilled technical support (calibration and
Very expensive (initial & ongoing costs)
Needs dedicated space
what is involved in a 6 minute walk test?
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
what is the primary outcome of the 6 minute walk test?
total distance walked in six minutes
what are the secondary outcomes of the 6 minute walk test?
‘perceived exertion’ scales, heart rate and pulse oximetry
list advantages of the 6 minute walk test
Patient-driven pace – speeding up, slowing down & rest OK
Cheap to deploy
Validated in many clinical populations
list disadvantages of the 6 minute walk test
Requires a significant unobstructed course, it often undertaken in a public hospital corridor
The pace is not reregulated
what is involved in a incremental shuttle walk test?
Uses a 10 m circuit
Externally paced by an audio recording (like bleep test)
Each minute has one extra length than the previous minute
what is the primary outcome of the incremental shuttle walk test?
total distance walked before volitional end
what are the secondary outcomes of the incremental shuttle walk test?
‘perceived exertion’ scales, heart rate and pulse oximetry
list advantages of the incremental shuttle walk test
Cheap to deploy
Validated in many clinical populations
The external pacing helps some to achieve maximum levels
list disadvantages of the incremental shuttle walk test
Requires an unobstructed course
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
exercise tests can be used for?
to monitor disease severity / progression and response to treatment
long term oxygen therapy is defined as?
> 15 hours / day
