Association between International Physical Activity Questionnaire and Triaxial Accelerometry in Detecting Intervention-Related Physical Activity Changes

Abstract

Cross-sectional studies have examined associations between the International Physical Activity Questionnaire (IPAQ) and objective physical activity (PA), though the responsiveness of the IPAQ to change in intervention studies has not been well explored. PURPOSE: To examine the association of PA changes assessed using the IPAQ and hip-worn triaxial accelerometry. METHODS: Participants were from two intervention studies which emphasized increasing physical activity: 1) healthy midlife women in a lifestyle intervention for reducing abdominal fat (n=44), 2) adults with diabetes in a randomized clinical trial for diabetes self-management (n=96 intervention; n=95 standard of care). Included participants completed both the 7-day version of the IPAQ and wore a triaxial accelerometer for 7 days at baseline and 12 months. IPAQ measures included: total PA (MET-min/week), weekly minutes of moderate-to-vigorous activity (MVPA), and walking minutes. PA from the accelerometer included average min/day of MVPA and light activity, steps/day, and min/week sustained MVPA (≥10 minute bouts) and was processed using vector-magnitude cut-points. Change in accelerometer-measured PA was also compared between tertiles of change in total IPAQ score. Associations between measures were compared using correlations and linear regression. RESULTS: Overall, participants’ (n=235; age 53.8 ± 9.8 years, 75.5% female, 89.4% black, BMI 35.4 ± 8.0 kg/m2) objective MVPA did not significantly change, while mean light activity increased (21.8 ± 78.6 more min/day, p<0.001) as did daily steps (217 ± 1709, p<0.01). Conversely, median IPAQ total PA declined, (-94, IQR: -1634.0 to 362.0, p<0.05) though other IPAQ measures did not significantly change. Change in accelerometer steps/day was weakly correlated with change in IPAQ total score and walking min/week (r= 0.16 and 0.14, respectively, p<0.05). Changes in accelerometer MVPA, light activity, and steps/day did not significantly differ by IPAQ change tertile. CONCLUSIONS: The IPAQ may be insufficient for capturing PA changes, particularly if changes are of light intensity. Future studies should assess the appropriateness of other PA assessment tools for better detection of intervention-related PA changes. Supported by NIH Grants: R01DK092271, 1P50HL105189-01, U01HL097894-01.