Review Article

European Journal of Applied Physiology

, Volume 105, Issue 6, pp 823-828

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Assessment of physical activity: a critical appraisal

  • Klaas R. WesterterpAffiliated withDepartment of Human Biology, Maastricht University Email author 


Assessment of physical activity in a free-living environment is important for understanding relations between physical activity and health and determining the effectiveness of interventions. Techniques include behavioral observation, questionnaires in the form of diaries, recall questionnaires and interviews, and physiological markers like heart rate, calorimetry, and motion sensors. The doubly labeled water method has become the gold standard for the validation of field methods of assessing physical activity. Then, questionnaires show a low reliability and validity but can be adequately applied as an activity-ranking instrument. The heart rate requires individual calibration to be an effective method to assess physical activity only at group level. The indicated method for the assessment of habitual physical activity in daily life is a doubly labeled water validated accelerometer. Future developments are simultaneous measurement of body acceleration and heart rate for the assessment of physical fitness. A new generation of accelerometers will provide information on body posture and activity recognition to allow objective assessment of subjects’ habitual activities, options for a healthy change, and effects of the follow-up of any changes.


Questionnaires Heart rate Accelerometers Doubly labeled water Physical fitness Activity type