Assessing Physical Activity

Question 1

What are Physical Activity Diaries and Logs?

Answer 1

• Physical activity Logs/Diaries are ongoing diaries kept by individuals that attempt to capture all sources and patterns of physical activity during a defined time frame.
• Some diaries are structured to record each activity undertaken in sequence and its associated duration. Others are structured to record activities performed at specified time intervals (e.g every 15 minutes).

Question 2

What is a Subjective Method?

Answer 2

• Subjective methods of assessing physical activity depend on our own perceptions.
• They are predominantly used for measurement in populations.

Question 3

What are the disadvantages of Physical Activity Diaries and Logs?

Answer 3

• logging activities can be tedious leading to inaccuracies
• reactivity - many people change their behaviour because of the self-monitoring process.
• not suitable for young children or elderly due to cognitive limitations

Question 4

What are Questionnaires and Recall Surveys?

Answer 4

• This method usually consists of short, simple questionnaires of approximately 5 to 15.
• They seek to investigate physical activity patterns in the recent past (e.g week, month or year).
• The main aim of this method is to provide basic data that can be used to assess physical activity patterns in large populations.
• Recall surveys generally require less effort by the respondent than diaries or logs.

Question 5

What are the advantages of Physical Activity Diaries and Logs?

Answer 5

• inexpensive
• allows collection of data about specific activities in their context
• data on dimensions gathered

Question 6

What are the advantages of Questionnaires and Recall Surveys?

Answer 6

• cheap and easy to use with large groups
• low impact on participants
• enables assessment of dimensions and domains of physical activity
• not likely to be reactive

Question 7

What are the disadvantages of Questionnaires and Recall Surveys?

Answer 7

• participants can over report physical activity levels
• participants may have difficulty recalling information
• not suitable for young children or elderly

Question 8

What is an Objective Method?

Answer 8

• Physical activity assessments using either direct observation or a device such as a pedometer or accelerometer are examples of objective measures.
• These methods are predominantly used for measurement in individuals.
• Objective methods offer a potential advantage over self reported data as it reduces bias from poor memory and over reporting or under reporting.

Question 9

What are Direct Observations?

Answer 9

• An observer is used to accurately describe what the participant does in a physical activity setting.
• The aim is to collect data that measures a participant’s physical activity by type, time, place and social setting.

Question 10

What are the advantages of Direct Observations?

Answer 10

• allows for a range of data to be gathered
• particularly useful amongst children
• enables assessment of dimensions and domains of physical activity

Question 11

What are Pedometers?

Answer 11

• Pedometers were designed to count steps and thus provide a potentially useful measure of distance.
• Pedometers can also be used to estimate physical activity energy expenditure by estimating the energy cost associated with walking.

Question 12

What are the disadvantages of Direct Observations?

Answer 12

• multiple observers required to gather complex data - expensive
• adequate training essential to ensure inter-rater reliability
• not suitable for all domains
• observers can influence physical activity patterns of individuals being observed (reactivity)

Question 13

What are the advantages of Pedometers?

Answer 13

• inexpensive
• small, lightweight and non-invasive
• easy to administer to large groups
• useful for detecting change (between pre- and post-tests) in the daily number of steps taken, or to identify changes in rank order among groups.
• objectively measures the most common physical activity behaviour (walking)
• Appropriate for use in a range of settings
• Provides immediate feedback and has the potential to promote behaviour change

Question 14

What are the disadvantages of Pedometers?

Answer 14

• Assesses only one type of physical activity behaviour (walking or running)
• Unable to record the magnitude of movement detected (a step is recorded regardless of the intensity or mode during walking, running or jumping)
• Provides no information about dimensions
• Not an appropriate choice of comparing children’s levels of physical maturity because of the influence of body size and speed of locomotion on step count.
• Can provide estimates of energy expenditure, however there are based on studies of adults and are inaccurate estimates for children

Question 15

What are Accelerometers?

Answer 15

• This method can be used to assess the acceleration of the body in certain directions.
• It can also:
Provide information on the frequency, duration and intensity of the activity

Provide minute by minute information that can be downloaded to a computer for analysis

Detect movement patterns throughout a day (e.g how much time a child spends in moderate and/or vigorous physical activity)

Question 16

What are the advantages of Accelerometers?

Answer 16

• record data in real time and are capable of measuring intensity; frequency and duration.
• low impact on participants
• useful to measure activity levels of children
• data can be stored for extended periods of time
• sensitive

Question 17

What are Heart Rate Monitors?

Answer 17

• A heart rate monitor is a device (usually a watch) that provides data on a participant’s heart rate response to physical activity
• Heart rate is typically used to estimate physical activity as energy expenditure (oxygen uptake), based on the assumption of a linear association between heart rate and energy expenditure

Question 18

What are the disadvantages of Accelerometers?

Answer 18

• expensive (from $250 - $3000)
• require computer software to analyse
• they are not sensitive to low impact physical activities and therefore underestimate movement during cycling and rollerblading or activities that are predominantly upper body
• complicated interpretation of data limits their practicality
• not suitable for large groups

Question 19

What are the advantages of Heart Rate Monitors?

Answer 19

• measures frequency, intensity and duration
• low impact on participants
• relatively accurate particularly at moderate and vigorous exercise intensities.

Question 20

What are the disadvantages of Heart Rate Monitors?

Answer 20

• expensive
• inaccuracy as heart rate is influenced by other factors such as stress and temperature
• not suitable for large groups