Background: Methodological limitations make comparison of various instruments difficult, although the number of publications on physical activity assessment has extensively increased. Therefore, systematization of techniques and definitions is essential for the improvement of knowledge in the area. Objective: This paper systematically describes and compares up-to-date methods that assess habitual physical activity and discusses main issues regarding the use and interpretation of data collected with these techniques. Methods: A general outline of the measures and techniques described above is presented in review form, along with their respective definition, usual applications, positive aspects and shortcomings. Results and Conclusions: The various factors to be considered in the selection of physical activity assessment methods include goals, sample size, budget, cultural and social/environmental factors, physical burden for the subject, and statistical factors, such as accuracy and precision. It is concluded that no single current technique is able to quantify all aspects of physical activity under free-living conditions, requiring the use of complementary methods. In not too distant future, devices will take advantage of consumer technologies, such as mobile phones, GPS devices. It is important to perform other activities, such as detecting and responding to physical activity in a real time, creating new opportunities in measurement, remote compliance monitoring, data-driven discovery and intervention.

Faculty of Health Care University of Presov in Presov Slovakia

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