Self-report measures are the most common approach to quantifying physical activity levels and patterns in free-living adult populations.  The three main types of subjective instruments are recall questionnaires, physical activity logs, and physical activity diaries.  Individual data obtained from self-report measures are typically converted into estimates, which allow researchers to categorize or rank individuals or populations by physical activity level.

Physical Activity Questionnaire

The physical activity questionnaire is the most practical self-report instrument in physical activity research.  Physical activity questionnaires are subjective recall instruments that vary in detail, type of activity assessed, reference periods, administration, completion time, targeted population, and how respondents are classified.  Due to their subjective nature, these instruments are inherently limited by factors such as recall error, social desirability or gender bias, floor effects, misinterpretation of terminology, and some questionnaires fail to quantify the totality of physical activity dimensions and contexts.  However, a plethora of questionnaires exist and many have already been successfully tested for validity and reliability in a range of target populations.  Some advantages to using questionnaires over other self-reporting instruments include:

• Low cost
• Applicable to a wide range of ages
• Wide distribution allows researchers to collect data from a large number of people
• Recall does not alter current behavior under study, which can occur with physical activity logs and diaries
• Measures can be adapted to fit the needs of a particular population or research question
• Several forms of administration (face-to-face, telephone interviews, mailed forms)

An EPARC staff member can assist you in choosing the appropriate measure(s) for your study.

Physical Activity Logs

Physical activity logs are continuous records of participation in specific types of listed activities.  The participant is required to record the duration and intensity immediately or shortly after one of the listed activities is performed.  This information can be utilized to calculate the energy cost of each activity and to determine the accumulated energy expenditure of daily activities.

Physical Activity Diaries

The diary technique of assessing habitual physical activity consists of periodic recording of all activities, either by the individual, an observer, or an interviewer. Activity diaries are superior to activity recall and are capable of simultaneously collecting data on many subjects at low cost. Recording frequency is determined by the investigator, and has ranged from every minute to every 4 hours, and is typically limited to 1-3 days. The detail of diary entries also varies, from meticulous records of every single activity throughout the day, to logging specific activities assigned to general categories.