Chapter 3 (exam review) Flashcards
subjective measures
questionnaires or interviews that are used to gather information about an individual’s physical activity habits (most feasible is self-report)
pros of subjective measures
- great for large scale studies
- very practical
- time efficient
- can provide a valid and reliable picture of a population’s PA
cons of subjective measure
- recall bias
- social desirability bias
- precision
- limited scope
pros of objective measures
- accurate
- detailed data
- reliable
- user feedback
- non-intrusive (sometimes)
cons of objective measures
- cost
- compliance issues
- activity type limitations
- data management/ cleaning
- sometimes intrusive
doubly labeled water
considered the “best” field measure for total energy expenditure
> participant drinks water w/ labeled H2 and O2 isotopes, urine sample is collected, diff between isotope elimination is analyzed = CO2, which is then converted to calories
Pros: ( accurate, reliable)
Cons: expensive, intrusive
Indirect Calorimetry
calculate energy expenditure
- oxygen we inhale
- carbon dioxide we exhale
Pros: accurate, reliable, less-intrusive
Cons: still expensive
Heart Rate Monitors
continuously monitor the amount of time spent in each intensity zone
Research grade= use of chest strap
Commercial=PPG (photoplethysmography)
Pros: non-invasive, can provide real-time feedback, less ambiguity around intensity
Cons: type of activity is hard to determine, susceptible to influence from external variables, hard to validate underlying algorithms for HR
Accelerometers
device that captures movement in different directions that we can then sometimes quantify in different intensities
- can derive step counts, activity counts, intensity, duration, and frequency
advantages of accelerometers
- accurate
- no recall bias
- versatile
- measures of all activity
disadvantages of accelerometers
- misclassifying activity types
- classifications of PA domains
- participant compliance
- complex data analysis
dose-response
the association between exposure and outcome becomes stronger with increased exposure
- can take different shapes depending on what component of FITT we measure
> Linear ( pos or neg)
> curvilinear ( pos or neg)
> Inverted-U
All-cause mortality
risk reduction: 30%
strength of evidence: strong
dose response: clear inverse
effective dose: 2-2.5 h per week of moderate-to-vigorous physical activity
Cardiorespiratory Health
risk reduction: 20-35%
strength of evidence: strong
dose response: clear inverse
Effective Dose: 800 MET-minutes per week of MVPA
Metabolic Health
risk reduction: 30-40%
strength of evidence: strong
dose response: inverse
effective dose: 2-2.5 h per week MVPA
what kind of information can surveillance studies provide?
- information on prevalence of physical inactivity across geographic areas
- trends in physical inactivity over time (ex: healthy people 2020/2030)
what type of physical activity measures are most commonly used? (surveillance)
wearable devices
FITT principle
factors that researchers measure in different domains
Frequency, Intensity, Time, and Type
Frequency
of times an activity is performed over a defined period
Intensity
- assumptions about certain activities, time spent in a particular HR zone, rate of perceived exertion
Metabolic Equivalent
Time
used to be: activity in bouts of at least 10 minutes
now: no minimum threshold required, every movement counts
Type
how to capture:
- combine self-report with objective measures
- employ mixed methods research designs
- utilize activity logs
Absolute Intensity
person A =/ person B
may not accurately reflect individual effort required to perform the brisk walk
Relative Intensity
required energy expenditure relative to a person’s maximal capacity (VO2 max)
- prescribing exercise or PA
