Assessment of Physical Activity in Adults: A Review of Validated Questionnaires From a Nutritionist's Point of View.

Physical activity (PA) is a component of total energy expenditure. PA and PA energy expenditure (PAEE) can be estimated by objective techniques (OTs). However, the use of questionnaires is frequent in clinical settings and epidemiological studies. We conducted a search on PubMed, Scopus, and Google Scholar databases to perform a review of studies reporting the reliability and validity of PA questionnaires validated against OTs-doubly labeled water (DLW) or accelerometers-in free-living adults. We selected original articles published between 2009 and 2019 that reported validation studies of PA questionnaires. We identified 53 studies that fulfilled the eligibility criteria. Four PA questionnaires were validated against DLW and the remaining against accelerometers. Three questionnaires were compared with both DLW and accelerometer results. The correlation between questionnaire-estimated PAEE and DLW results ranged from r = .22 to r = .46, while that between questionnaire-estimated total PA (TPA) and accelerometer results ranged from r = .11 to r = .54 The intraclass correlation coefficients were between .56 and .84. Despite having good reliability, most of the questionnaires included in this review have shown limited validity for estimating TPA in adults. OTs should be considered as a first option, when possible. Further research is warranted on techniques to obtain more accurate PA and PAEE estimates.