Evaluation of the circumplex structure of the Activation Deactivation Adjective Check List before and after a short walk

Background and purpose: The Activation Deactivation Adjective Check List (AD ACL; Thayer, 1989, The biopsychology of mood and arousal. New York: Oxford University Press) has been used in several studies to assess affective responses to bouts of physical activity. In recent years, researchers have suggested that the structure of this multidimensional measure should approximate a circumplex. This hypothesis was examined using a circumplex-specific confirmatory method. Methods: Volunteers (n=165) completed the AD ACL before and after a short walk. The data were analyzed using Browne's Circumplex models for correlation matrices. (Psychometrika, 57, 469-497) circular stochastic process model and CIRCUM software and the analyses were performed at the item level. Results and conclusions: Before the walk, the circumplex provided a close fit to the data, whereas, after the walk, the fit was lower, but still reasonable. At neither time did items theorized to belong to one subscale become interspersed with items theorized to belong to an adjacent subscale. The AD ACL represents a satisfactory, albeit imperfect, option for the assessment of affective responses to physical activity from a circumplex perspective. In the future, closer fit to circumplex structure should be achieved by taking the specific structural postulates of the circumplex model into account from the beginning of the scale development process.