Podcast Beta
Questions and Answers
What are the advantages of a bike test?
Standardize speed, Many available formulas to calculate work done, calories expended, aerobic capacity, Easier to measure power output and parameters, Portable and less expensive, Lower oxygen consumption & desaturation
List some disadvantages of a bike test.
May not be suitable for those who have knee pain when cycling, Expertise interpreting parameters, Blood pressure may be greater due to greater muscular contraction, Limited usually by leg fatigue than dyspnea
What are the factors affecting Stroke Volume (SV)?
VE/VO2 can be used as an index of ventilatory efficiency.
Signup and view all the answers
What is FIO2 in the context of ventilation?
Signup and view all the answers
List three objectives related to exercise assessments.
Signup and view all the answers
What are some additional contraindications for exercise testing? (Select all that apply)
Signup and view all the answers
CPET is used to determine peak oxygen consumption and level of disability.
Signup and view all the answers
What is one possible reason to terminate an exercise test? Patient requests to terminate the test due to ________.
Signup and view all the answers
Match the possible mechanism of exercise limitations with the correct category:
Signup and view all the answers
What is the purpose of the 6MWT?
Signup and view all the answers
What should the patient do if they need to stop during the 6MWT?
Signup and view all the answers
What distance should be used for exercise prescription if the ISWD is 330m?
Signup and view all the answers
The 6MWT can result in a significant learning effect on the second test.
Signup and view all the answers
What is the formula to calculate METs using the 6MWT, given the 6-minute walking distance is represented by $6MWD$?
Signup and view all the answers
Study Notes
Exercise Assessments
- Objectives of exercise assessments:
- Knowledge of range of assessment tests/tools
- Appraising various assessments in different patient population groups (Evidence-Based Medicine)
- Understanding precautions and contraindications to exercise tests
- Interpretation and justification of suitable assessments
- Calculation or estimation of energy expenditure (ACSM)
Contraindications for Exercise Testing
- Absolute contraindications:
- Unstable angina or AMI (Non STEMI) during the previous month
- Severe pulmonary hypertension
- Pre-exercise heart rate > 125bpm
- Resting SpO2 < 90%
- Relative contraindications:
- Physical disability preventing safe performance (e.g. balance problems, unsteady gait)
Criteria to Terminate Test
- Patient requests to terminate the test
- Any untoward medical occurrence, sign, or symptom during the test
- Onset of chest pain suggestive of ischaemia
- Abnormal HR response
- Signs or symptoms of poor perfusion
- Development of an abnormal gait/loss of coordination
- Signs suggestive of mental confusion
Clinical Utility of CardioPulmonary Exercise Testing (CPET)
- To determine peak oxygen consumption (VO2) and level of disability
- To screen for coexistent ischemic heart disease, peripheral vascular disease, and arterial hypoxemia
- To generate prognostic information
- To assist in planning individualized exercise training
Cardiorespiratory Fitness Tests
- Maximal protocols:
- Pros: direct results, not estimates
- Cons: usually need technical equipment, stressful and distressing for subjects
- Sub-maximal protocols:
- Pros: easy to administer, less stressful
- Cons: results are estimates, not exact figures
PAR-Q (Physical Activity Readiness Questionnaire)
- 7 questions to assess the risk of exercising:
- Has your doctor ever said you have a heart condition or high blood pressure?
- Do you feel pain in your chest at rest, during daily activities, or when doing physical activity?
- Do you lose balance because of dizziness or have you lost consciousness in the last 12 months?
- Have you ever been diagnosed with another chronic medical condition?
- Are you currently taking prescribed medications for a chronic medical condition?
- Do you currently have a bone, joint, or soft tissue problem?
- Has your doctor ever said you should only do medically supervised physical activity?
Possible Follow-Up Questions
- For each "yes" answer in the PAR-Q, ask further questions to clarify the situation
Possible Mechanisms of Exercise Limitations
- Peripheral:
- Inactivity/sedentariness
- Muscle atrophy
- Neuromuscular dysfunction
- Reduced oxidative capacity
- Malnutrition
- Joint pain
- Pulmonary:
- Ventilation
- Respiratory muscle dysfunction
- Impaired gas exchange
- Cardiovascular:
- Reduced SV
- Abnormality of HR responses
- Abnormality of circulation
- Abnormality of blood
Aerobic Fitness or Exercise Tests
- Field walk tests
- Treadmill protocols
- Bike tests
Field Tests (Walking Tests)
- Examples:
- 6-Minute Walk Test (6MWT)
- Incremental Shuttle Walk Test (ISWT)
- Important considerations:
- Need for proper technique and encouragement
- Strong learning effect on second test
- Prediction formulas for VO2max and METs
6-Minute Walk Test (6MWT)
- Procedure:
- Walk as far as possible in 6 minutes
- Use a 30-meter walkway
- Fixed/standardized encouragement
- Rests allowed
- Chairs set up for resting
- Prediction formulas for VO2max:
- Various formulas available for different populations
- Exercise prescription using 6MWT:
- Calculate average speed
- Prescribe at 80% average speed
- Progression: increase distance, speed, or duration
Incremental Shuttle Walk Test (ISWT)
- Procedure:
- Walk back and forth along a 10-meter course
- Speed increases every minute
- No encouragement
- Strong learning effect on second test
- Prediction formulas for VO2max:
- Various formulas available for different populations
- Important considerations:
- Not suitable for patients using walking aids or supplementary oxygen
- Minimum speed is 1.8 km/h
- Must be able to follow the rhythm of the audio signals### Exercise Prescription and Testing
- Prediction formulas for VO2max:
- 0.03 X distance (m) + 3.98 (Cahalin, 1996)
- 4.948 + 0.023 X distance (m) (Ross, 2010)
- METs calculation: {(6MWD / 6) (0.1 ml/kg/min) + 3.5 ml/kg/min} / (3.5)
- 1 MET = 3.5 ml/kg/min VO2
Incremental Shuttle Walk Test (ISWT)
- ISWD = 330m (level 6)
- Peak walking speed = 4.86km/h
- Exercise prescription: 75% peak speed = 3.65km/h
- 20min walking goal = 3.65 / 3 = 1.21km
- Target: 1200m at least in 20 minutes (excluding rests)
Progression
- Increase distance in 20min (increase speed)
- Reduce rest time or number of rests
- Increase duration to 25-30min
Other Tests
- Step tests: Harvard, Chester, YMCA, and 2-minute step test
- Treadmill protocols: Bruce, Naughton-Balke, and Ramp protocols
- Advantages: standardize speed and/or ramp, many available formulas to calculate work done, calories expended, and aerobic capacity
- Disadvantages: familiarity with walking on treadmills, expensive, expertise in interpreting parameters, space, and not suitable for those with walking aids
Bike Test
- Advantages: standardize speed, many available formulas, easier to measure power output, portable, and less expensive
- Disadvantages: may not be suitable for those with knee pain, expertise in interpreting parameters, and blood pressure may be greater due to greater muscular contraction
Example of an Step Incremental Cycle Test
- Cycling speed: 60 revolutions per minute
- Warm-up: 3 minutes at 10 W and 2 minutes at 20 W
- Test: cycling for 2 minutes against a work rate of 30 W, increasing by 10 W every 2 minutes until symptom-limited endpoint
Example of a Ramp Incremental Cycle Test
- Cycling speed: 60 revolutions per minute
- First 2 minutes: pedaling at 0 W
- Increase to 20W in the next minute
- Increase by 20W at every minute, until termination
- Test duration: 6-12 minutes, excluding the 2 minutes at 0W
VO2 Max Test
- Equipment: O2 and CO2 analyser, workload modifiable ergometer, and stopwatch
- Reliability: 0.97 or greater
- Procedure: performed on a treadmill, cycle, or rowing ergometer, until peak VO2 is reached, indicated by peak VO2 plateau, respiratory exchange ratio of 1.15, or voluntary exhaustion
- Advantages: most accurate to measure VO2 aerobic capacity
- Disadvantages: expensive equipment, requires high tester experience
Comparison between VO2peak obtained on a cycle ergometer versus a treadmill
- Peak exercise capacity on a cycle ergometer can range between 5 to 20% lower than on a treadmill
- Possible reasons: regional muscle fatigue, interindividual variability, and data from different studies
- Exceptions: highly trained cyclists may have higher exercise capacity on a cycle ergometer
Revision: Fick Equation
- Factors affecting stroke volume (SV), heart rate (HR), and a-v difference: cardiac responses, pulmonary responses, muscle diseases, deconditioning, anemia, low iron, and pulmonary disease
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Assessments and exercise tests for different patient populations, including CPET, aerobic fitness, strength, flexibility, and balance. Understanding precautions, contraindications, and interpretation of results.
