Cardiopulm Unit 3 Exercise Training and Prescription Flashcards
What are the Indications for Exercise Stress Test?
What is the purpose of Exercise Testing for PTs?
- Evaluate activity limitations
- Establish safety for physical activity/exercise participation
- Collect the necessary information to write an appropriate physical activity/exercise prescription that is less likely to be under- or over-dosed
- Collect baseline data for outcome assessment
What is VO2?
A measure of oxygen consumption
HR x SV x (aO2 - vO2)
(HR x SV = Cardiac output)
aO2: oxygen in arteries (pre-capillary)
vO2: oxygen in veins (post-capillary)
From rest to maximal exercise, how much does Cardiac output, HR, SV, a-VO2 and VO2increase? When a person is ~40% of maximum work, what happens to their SV?
- Cardiac output can increase ~4x
- HR can increase ~3x
- SV can increase ~1.5x
- By ~40% maximum work, rate of increase in SV tapers and remainder of increasing CO is due to HR
- a-VO2 difference can increase ~3x
- The body can account for increase ~12x between rest and maximal exercise
What can having a “Normal” VO2 mean, and how is this important?
Having a “Normal” VO2 (around >85% predicted for your age, gender etc.) essentially rules out significant cardiovascular and pulmonary disease
The greater the amount of oxygen consumed at peak exercise, the more fit the individual
Is HR more useful for Aerobic or Anaerobic exercise training?
Aerobic
What is the normal HR response to incremental exercise?
There is an increase with progressive workloads at a rate of ~10bpm per 1 MET
MET: A unit that describes how much oxygen someone is consuming at rest
For ex: If a person is doing an exercise at 2 METS of intensity, this means that the exercise is having the person consume twice the amounnt of oxygen as they perform at rest
What makes heart rate a reliable indicator for exercise intensity during an incremental exercise test?
Heart rate is a reliable indicator because it has a linear relationship with %VO2max, enabling accurate assessment and prescription of exercise intensity.
Exercise intensity is directly associated to what?
Both the amount of improvement in exercise capacity and the risk of adverse events during exercise
HR responses to exercise provide information to what?
The fitness of the individual where exaggerated responses suggest relatively less fitness
- Exercise training promotes a decreased HR responseto submaximal workload
What is the normal BP response to exercise?
- Systolic BP (SBP): Gradual rate of rise (~10mmHG/MET) until reaching steady state
- Diastolic BP (DBP): Increases or decreases withing 10mmHG
What is a Hypertensive Response to exercise?
- A SBP ≥ 210 mmHG in men and ≥ 190 mmHG in women during exercise is often considered a hypertensive response
- A DBP ≥ of 110 mmHG is often considered a hypersensive response
What is a Hypotensive Response to exercise? What is this often associated with?
- A decrease of SBP by > 10 mmHG with or without a preliminary increase is considered abnormal and often associated with myocardial ischemia, left ventricular dysfunction, and an increase risk of subsequent cardiac events
This is a serious concern
What does the term “Regular Exercise” mean?
Performing planned structured physcial activity for at leat 30 minutes at a moderate intensity at least 3 days per week for the last 3 months
Anyone who does not meet that criteria is said to not be a regular exercise participant
What is considered Light-Intensity Exercise?
30-39% HRR or VO2R, 2-2.9 METs, RPE 9-11. An intensity that causes slight increases in HR and breathing
(HRR: Heart Rate Reserve), (VO2R: Oxygen uptake reserve)
What is considered Moderate-Intensity Exercise
40-59% HRR or VO2R, ≥ 3-5.9 METs, RPE 12-13. An intensity that causes noticible increases in HR and breathing
What is considered Vigorous-Intensity Exercise?
≥60% HRR or VO2R, ≥ 6METs, RPE ≥14. An intensity that causes substantial increases in HR and breathing
Pre-Exercise Screen
What is recommended for a person that does not participate in regular exercise and does not have CV, metabolic, or renal disease AND no S/S suggestive of CV, metabolic or renal disease?
- Medical Clearance is not necessary
- Light to moderate-intensity exercise recommended
- May gradually progress to vigorous-intensity exercise follwing ACSM guidelines
Medical clearance is approval from a healthcare progessional
Pre-exercise Screen
What is recommended for a person that does not participate in regular exercise and has Known CV, Metabolic, or Renal disease and Asymptomatic?
- Medical Clearance Recommended
- Following medical clearance, light to moderate-intensity exercise recommended
- May gradually progress as tolerated following ACSM guidelines
Pre-exercise Screening
What is recommended for a person that does not participate in regular exercsie and has any S/S suggestive of CV, metabolic or Renal disease (regardless of disease status)?
- Medical Clearance Recommended
- Following medical clearance, light-moderate intensity exercise recommended
- May gradually progress as tolerated following ACSM guidelines
Pre-exercise Screen
What is recommended for a person that does participate in regular exercise and does not have CV, metabolic, or Renal disease and S/S suggestive of CV, metabolic or renal disease?
- Medical clearance is not necessary
- Continue moderate or vigorous-intensity exercise
- May gradually progress following ACSM guidelines
Pre-exercise Screen
What is recommended for a person that does participate in regular exercise and has Known CV, Metabolic, or Renal disease and Asymptomatic?
- Medical clearance for moderate-intensity exercise NOT necessary
- Medical clearance (within the past 12 months if no change in S/S) recommended before engaging in vigorous-intensity exercise
- Continue with moderate-intensity exercise
- Following medical clearance, may gradually progress as tolerated following ACSM guidelines
Pre-exercise Screen
What is recommended for a person that does participate in regular exercsie and has any S/S suggestive of CV, metabolic or Renal disease (regardless of disease status)?
- Discontinue exercise and seek medical clearance
- May return to exercise following medical clearance
- Gradually progress as tolerated following ACSM guidelines
What is a Symptom (Sx) Limited/Max Exercise Test (ET)?
Exercise terminated at maximal exertion or clinical limitation
What are the Common Indications of doing Sx-Limited/Max Exercise Test (ET)?
- Dx suspected myocardial Ischemia/CAD
- Risk stratification, prognosis, assessing medical therapy and cardiopulmonary reserve
- Assessing Cardiorespiratory Fitness (CRF), the ability of the circulatory and respiratory systems to supply oxygen to skeletal muscles during sustained physical activity. These may or may not utilize ventilatory gas analysis (Cardiopulmonary Exercise Test [CPET])
What is Submaximal Exercise Testing (ET)?
Exercise terminated on achievement of a predetermined end point
Examples of endpoints:
- x bpm above resting, & predicted max HR (PMHR), %HRR
- Targert RPE or Dyspnea rating
- Workload (e.g. MET, Watts)
- Time (e.g., 6 MWT)
- Distance (Cooper 1.5 mile run test)
What is Low-Level ET?
A subset of submax testing that is sometimes described as being useful in acute setting (e.g., post-MI/CABG) in attempt to identify the high risk patient (e.g., before discharging from acute care)
- Steady intensity or ramping/increasing workload to about 2-6 METs
What are the steps taken to Prepare an ET?
- Ensure the pt has no absolute contraindications. Ensure all relative contraindications are considered
- Determine the Mode:
-What mode best represents the activity limitations the pt needs to improve
-The ET mode should resemble the eventual exercise you’re going to prescribe
–What does the patient want or like to do? - If not standardized, determine the end-point of the test
-Standard submaximal testing works up to 85% of age-predicted maximal heart rate
-A total rest time of 8-12 min is often recommended as it is sufficient to evaluate cardiovascular function without overly fatiguing a pt.
What are the Absolute Indications that the patient is unstable and Treatment should (Totally) be withheld?
- S/S of decompensated Cogestive Heart Failure
- > 10 PVCs/minute at rest
- Mutlifocal PVCs, unstable angina, and ECG changes associatd with ischemia/injury
- Dissecting aortic aneurism
- New Onset (< 24 hrs) A-fib with rapid ventricular response (RVR) > 100bpm (at rest)
- 2nd degree-heart block coupled with ventricular tachycardia
- 3rd degree heart block
- Chest pain with new ST segment changes on ECG
What are the Relative (it depends) indications that a patient is unstable and treatment should be Modified or withheld?
- Resting tachycardia (especially if new)
- Resting SBP > 160 or DBP > 90 (Escpecially if new)
- Resting SBP < 80
- Ventricular ectopy at rest
- MI or extension of infarction within previous 2 days
- Uncontrolled Metabolic Disease (e.g., DM)
- Psychosis or other unstable psychologic condition
With ETs, what are Modes?
What are considerations PT need to have with ETs?
- ETs generally become more useful the closer they approximate a maximal test. This is because:
–Predicting maximal work and physiological capacity becomes more accurate
–Testing at higher intensities provides the clinician with a sense of how safe higher intensity exercise might be - Beta blockers and some calcium-channel blockers reduce both resting and exercising heart rates but do not affect the relationship between HR percentage and oxygen consumption percentage
–It is crucial for individuals to be in constant medication during both the initial exercise test and subsequent training, if there is any change in medication or dosage, a repeat exercise test is necessary to accurately set the training heart rate
What are different methods to predict max HR and work capacity?
- 220-age= predicted max HR (PMHR)
(This may overestimate true HRmax in young adults and underestimate true HRmax in persons older than 40) - 208-(0.7 x age)
(This more accurately identifies true HRmax among healthy adults across the life span, Still has a wide variation of 10-12bpm)
-With this, you also multiply by 85% (.85) to get the endpoint bpm
What is the method to predict max HR and work capacity specifically for individuals on Beta-Blockers?
164-(0.7 x age)
Why should Rate of Perceived Exertion scales always be considered with ET?
For collaborating HR-based measures and/or as a standalone way to assess exercise intensity. RPE is especially useful in accounting for medication effects on HR, autonomic dysfunction and arrythmias
With RPEs, why would this scale be useful for PTs?
This scale is used for steady state aerobic work (e.g., walking, biking). It provides a LINEAR correlation between perceived exertion and HR, ranging from 6-20, corresponding to a heart rate range of 60 to 200bpm in health individuals.
- So if a person says the exercise was a 11 on the scale, we would multiply by 10 and we would estimate their HR to be 110bpm.
With RPEs, why would this scale be useful for PTs?
The Category-Ratio (CR10) scale employs a non-linear scale, which can provide finer differentiation of more intense symptoms such as pain, shortness of breath, resistance
training efforts, and high-intensity aerobic exercise.
According to the ACSM, what are the ET Protocol General Format?
- Assess resting vitals
- Based on subjective and physcial inspection, define an individualized work rate progression that will achieve the desired end-point within about 8 to 12 miin after a low intensity warm-up
- Perform warm-up/familiarization period
- Assess vitals 1-2 times during each stage. Consider assessment of other subjective information (e.g., RPE, dyspnea)
-consider remaining in each stage until HR stabilizes - Terminate test upon achievement or predetermined end-poin, observations of adverse S/S or upon patient request to stop
- Provide cool-down / recovery period around the 1 stage work rate
- Perform physiologic observation for at least 15 minutes following ET
-Failure of the HR to decrease by at least 12bpm during the first minute or 22mbp by end of 2 min after exercise suggest increased risk of mortality in individuals with ischemic heart disease
-SBP typically returns to pre-exercise levles or lower by 6 min of recovery
-Some individuals pay experience post-exercise/recovery ischemia or other dysrhythmias (e.g., PVCs)
What are some reasons for Termination of Submaximal Testing?
- Pt request to stop
- A predetermined physiologic or other end-point has been reached
- Technical failure of any monitoring equipment
- Excessive dyspnea (using 0-10 Borg scale; will depend on case by case level)
- Sustained ventricular tachycardia
- Changes to cardiac rhythm as assessed by ECG, palpation or auscultion
- SpO2 drops below prescribed levels
- ST-Stegmetn depression ≥ 1 mm or reports of sx that could be angina
- Max tolerable (Grade 3) claudication pain
- Decreased in SBP > 10 mmHG or if SBP decreases from resting value obtained in same postural position prior to testing
- Consider cut off at a exaggerated BP response (SBP > 210 mmHG or Diastolic >115 mmHG; this will vary case-by-case)
With findings from an ET, what can we say about the patients likely maximal work capacity?
We can likely estimate peak workload to be 1-2 stages above near-maximal performance to provide information for exercise prescription
