Concordance Between Accelerometer-derived And Self-reported Physical Activity And Sedentary Time In Adults With Autism

Abstract

Despite the overall poor health profiles documented in adults with autism spectrum disorder (ASD), there is little information on physical activity (PA) and sedentary time in this population, and the agreement between objective and subjective measures of these variables in adults with ASD is unknown. PURPOSE: To examine the concordance between accelerometry-measured and self-reported PA and sedentary time in adults with ASD. METHODS: Twenty-four adults with ASD wore GT3X+ tri-axial accelerometers (ActiGraph, Pensacola, FL) for seven consecutive days and completed the International Physical Activity Questionnaire-Short Form (IPAQ-SF) on the last day of their study participation to estimate PA and sedentary time. The standardized IPAQ-SF guidelines and commonly used ActiGraph data cleaning principles were employed to process subjective and objective measurements, respectively. Paired sample t-tests and Bland-Altman plots were utilized to assess the difference and magnitude of agreement between the two measures. RESULTS: (1) Nearly 80% of the participants accumulated the recommended ≥150 minutes of moderate to vigorous PA (MVPA) while they were also highly sedentary (593.8 ± 106.9 min/day) according to accelerometry data. (2) Bland-Altman plots demonstrated that adults with ASD tended to overreport MVPA and underreport sedentary time via the IPAQ-SF, as compared to objective accelerometry-based measurements. CONCLUSIONS: It is suggested that PA intervention strategies for adults with ASD focus on reducing sedentary time as an independent health risk factor. Caution should be used when interpreting MVPA and sedentary time assessed by the IPAQ-SF due to potential over- and underestimation, respectively, in adults with ASD. Supported by the ACSM Foundation Doctoral Student Research Grant from the American College of Sports Medicine Foundation.Figure