Aerobic Assessment 1 Flashcards
The power and capacity of energy supply is dependent on the _____ and _____ of the exercise bout (or test).
- intensity
- duration
We can only assess which energy system ______.
predominates
___ is one of the best clinical indicators of health and health outcomes.
VO2
Aerobic system function =
VO2
VO2 is important for …
- performance (aerobic sports)
- health
VO2 can somewhat predict success in _____ activities.
endurance
VO2 can somewhat indicate the ability to _____ from task.
recover
VO2 has bee linked to ____ ____ for a variety of diseases.
increased risk
Gold standard for assessing aerobic power is considered to be…
maximal oxygen consumption test or VO2 max test
What is the single best measure of overall aerobic fitness?
VO2 max
Aerobic power:
maximum rate at which O2 can be inspired, transported, and utilized to perform muscular work
Aerobic power is defined by the ____ equation.
Fick
Absolute VO2:
total volume of oxygen taken up by the body (L/min)
Relative VO2:
volume of oxygen taken up by the body per unit of body weight (mL/kg/min)
How to assess aerobic power (VO2 max) using metabolic measurement system:
based on relationship between the volume of oxygen inspired vs volume of oxygen expired
How to assess aerobic power (VO2 max) using treadmill:
- considered the gold standard machine for eliciting VO2 max
- elicits VO2 max 5-11% higher than cycling
When assessing aerobic power (VO2 max), protocols that increase _____ only are not recommended.
speed
Speed mean VO2 max =
46.2 ml/kg/min
Grade mean VO2 max =
62.6 ml/kg/min
Modifications for VO2 max treadmill:
- slower initial speed for inexperienced
- start with walk and increase speed first then % grade later
- many different protocols available
End of test criteria required for a valid measurement of VO2 max:
- peak and plateau (< 150 ml/min) in oxygen consumption with an increase in work rate
- respiratory exchange ratio greater than 1.15
- achievement of predicted HRmax
- venous lactate concentration > 8 mM
- RPE > 17 (6-20 original) or 10 (0-10 revised) Borg Scale
- volitional exhaustion
Contraindications for VO2 max:
- drop in systolic BP of 10 mmHg with increase in workload or dizziness, near fainting
- hypertensive response (BP > 250/115 mmHg)
- chest pain or angina
- signs of poor perfusion (cyanosis or pallor)
- abnormal ECG recording
- cramping, extreme fatigue
True VO2 max:
- must utilize a large overall muscle mass
- requires working against gravity (non body mass supported)
- accomplished on a treadmill
Peak VO2 max:
all other exercise machines/modalities
How to know if test data is valid:
- post gas check (gas analyzers)
- do the parameters follow the desired trends? (VE, FECO2, FEO2, VO2 close to expected/normative values?)
VE (L/min) at rest and changes during incremental exercise:
- at rest: 8-12
- changes: increase up to 150 + L/min
TV (L/breath) at rest and changes during incremental exercise:
- at rest: 500 mL
- changes: increase during exercise, plateaus at ~ 4.0 L
RR (breaths/min) at rest and changes during incremental exercise:
- at rest: 12-15
- changes: rapidly increase at high exercise intensities up to 50+ bpm
VO2 (ml/kg/min) at rest and changes during incremental exercise:
- at rest: 5.0
- changes: increase linearly up to 30+ (untrained) and 50+ (trained)
VCO2 (L/min) at rest and changes during incremental exercise:
- at rest: ~ 4.0
- changes: increase linearly, closely matched with VE
RER at rest and changes during incremental exercise:
- at rest: 0.75-0.80
- changes: increase with values exceeding 1.1-1.2 at max
VE/VO2 at rest and changes during incremental exercise:
- at rest: in the 30s
- changes: initial decrease from rest to submax exercise followed by a rapid increase during more intense exercise
VE/VCO2 at rest and changes during incremental exercise:
- at rest: in the 30s
- changes: initial decrease, remains relatively constant throughout submax, followed by a steady increase beyond AT
Variability in VO2 max testing: Katch et al. (1982):
- tested 5 subjects between 8 and 21 times
- found that VO2 max varied +/- 5.6% (1 SD) and +/- 11.2% (2 SD)
- roughly 3-5 ml/kg/min for a 50 ml/kg.min individual
Variability in VO2 max testing: Thoden (1992):
approximately +/- 3 ml/kg/min for athletes
Bell (1989) reliability for VO2 max testing:
test retest r = 0.96 for rowing VO2 max
What if you don’t have a metabolic cart?
- a variety of protocols and formulas exist to predict VO2 max
- can be either maximal or submaximal
- regardless, they use some sort of physiological performance indicator in a formula to provide a predicted VO2max or VO2peak
Indirect submaximal VO2 max tests:
- mCAFT
- YMCA
- Astrand
- PWC
- ACSM
- Ebelling
- Rockport
Indirect maximal VO2 max tests:
- Leger
- Bruce
- Mod. Bruce
- Balke
- Cooper
What do you need for indirect calculation of VO2?
- VO2
- speed (m/min)
- BM (kg)
- grade
- work rate (kg/m/min)
- stepping frequency (min.)
- step height (m)
Other maximal indirect tests:
- multi-staged
- treadmill preferred (5-11% higher than bike)
- good estimation of true VO2 max
- protocol can be adapted for many populations
Bruce Treadmill test is a _____, ______ exercise test to _____.
- continuous
- progressive
- fatigue (volitional exhaustion)
Bruce Treadmill test correlates well to actual ____.
VO2 max
Bruce starts at….
- 10% grade, 1.7 mph
- increase speed and grade every 3 min.
Bruce: time to _____ is recorded.
exhaustion
Bruce: VO2 prediction can be performed:
- using a monogram which aligns exercise time with predicted VO2
- using participant specific equations
The Naughton treadmill test is a ______, _____ exercise test to _____.
- continuous
- progressive
- fatigue (volitional exhaustion)
The Naughton treadmill test is specific to what type of individuals?
higher risk individuals
The Naughton treadmill tests starts at….
- 0% grade and 1.0 mph
- increased speed at 2 min (2 mph), and grade (+3.5%) every 2 min.
Naughton: time to ______ is recorded.
exhaustion
Cycle ergometry maximal prediction mode:
- can be discontinuous or continuous
- max power output (W) attained is used to estimate VO2
Limitations of cycle ergometry:
?
Leger:
- maximal
- 20m shuttle run test
- need MAS (max aerobic running speed in km/hr)
Coopers:
- maximal
- 12 minute run test
- need distance (m)
Why use predictive submaximal VO2 max tests?
- safe, avoids max cardiovascular stress
- relatively inexpensive
- less sophisticated equipment required
- less expertise required
- more conducive to “mass” testing
- some test protocol durations are shorter than maximal protocols
Submaximal tests for predicting VO2 max is based on:
- positive linear relationship between power output, VO2 and HR
- assumption that max HR can be predicted similar in all individuals
- assumption that variability in HR (day to day) is minimal
- assumption that efficiency of exercise is similar between individuals at max
Best predictive power using HR occurs between HR’s of….
- 120-170 bpm
- prediction may be less accurate above and below these HR’s (10-20%)
Predicting VO2 max using a multi-stage equation: cycling ergometer test needs:
- weight
- HR
- age
Steps for predicting VO2 max using a multi-stage equation:
- determine power output for each stage (ACSM metabolic equation for cycle ergometry)
- determine slope of the line of best fit (use first submaximal workload and final exercise stage)
- determine VO2 max
How to predict VO2 max by graphing:
- use metabolic equations to calculate VO2 for each stage
- plot HR (end stage, 3rd min only) vs calculated VO2 and extrapolate to age predicted HR max
Ebbeling treadmill test is a ___ stage protocol designed for ….
- single
- healthy adults between 20-59 years
Ebbeling warm up:
- 4 min at 2.0-4.5 mph, 0% grade
- HR should be between 50-70% HRmax
Ebbeling work load:
4 min at 5% grade (same speed as warm up)
What is needed to calculate VO2 max from Ebbeling?
- speed (mph)
- HR (bpm)
- sex (1 or 0)
- age
Rockport 1 mile walk test was created for…
- males & females from 20-69 years
- may be more appropriate for older & sedentary populations
What is required for Rockport?
1 mile (1.6 km) track (not a treadmill)
Rockport protocol:
- walk 1 mile as quickly as possible without speed walking
- measure HR immediately at end of test
What is needed to calculate VO2 max from Rockport?
- age
- sex (1 or 0)
- time (min)
- HR (bpm)
General protocol for warm up and cool down:
- warm up: 5 min at low intensity at 20-30% HRR or 35-45% HR max
- warm up: similar movements as activity
- monitor HR, BP, RPE, symptoms prior to, during and after exercise (1, 3 and 5 min)
- cool down: active recovery for 5-10 minutes
Critical competency is the ability to measure:
- resting and post-exercise BP
- resting, steady state exercise, and post exercise HR via palpation
Limitations to submax tests:
- other factors affecting HR
- achievement of steady state
- age predicted maxHR formulas have a degree of error
- over/underestimation
Other factors affecting HR include….
- anxiety
- temp.
- caffeine
- talking
- body position
Describe how age predicted maxHR formulas have a degree of error.
- 220 - age = HR max
- 208 - 0.7*age = HR max
- predicted HRmax can vary +/- 10-12 beats
Over/underestimation can occur with what populations?
- athletes
- sedentary
- older population
Stress testing tests _____ _____ by….
- cardiac function
- increasing HR and myocardial contractility
Stress testing protocol:
- incremental exercise protocol
- includes 12 lead ECG plus BP measurements
- subjective symptoms (Borg, Angina, Claudication scales)
Stress tests are completed as part of…
an annual checkup or physical used for screening as part of physician clearance
Why have a stress test?
- prognostic
- diagnose
- functional
Prognostic use of stress test:
assessing patients with risk factors
Diagnose use of stress test:
coronary artery disease and symptoms such as chest pain, shortness of breath or lightheadedness
Functional uses of stress test:
- to assess a procedure that may be used to improve coronary artery circulation
- to determine a safe level of exercise for rehab or daily living
Fick Equation:
VO2 = Q x a-v O2 diff
Absolute VO2 is useful for…
PA where body weight is not carried (ie. rowing, cycling)
Relative VO2 allows for…
individuals of different sizes to be compared
Relative VO2 may underestimate VO2 max of….
obese individuals
Submaximal tests for predicting VO2 max are based on the _____ linear relationship between…
- positive
- power output
- VO2
- HR