Abstract
The association between objective and self-report assessments of physical activity is typically considered an indicator of measurement validity for the self-report. This study considered intraindividual associations between weekly self-reported physical activity recall and pedometer steps as individual differences. We hypothesized that people with high physical activity habits would be worse at retrospectively reporting their physical activity behaviors due to a lack of awareness of automatic behaviors.
Undergraduate students (N = 31, 19 women) completed an assessment of physical activity habit and weekly self-reports of physical activity (Leisure Time Exercise Questionnaire) while concurrently wearing pedometers for four weeks as part of a class assignment. A multilevel random effects model was tested to accommodate the weekly data nested within people.
Both weekly variation in and overall self-reported physical activity predicted weekly steps (?weekly= 73.57, p < .05; ?average= 19.29, p < .05). In addition, people who had stronger physical activity habits had weaker associations between self-report and steps than people with weaker physical activity habits (? = -12.86, p < .05). These results suggest self-reports of physical activity are underestimated by people with high physical activity habits. We speculate a lack of awareness may be the mechanism behind this finding, however; future research is necessary to support this theory.
