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Preliminary Evaluation of a 1-Day Acceptance and Commitment Therapy Workshop for Increasing Moderate-to-Vigorous
Jason Lillis1, Leah M Schumacher2, Dale S Bond2
1Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University/The Miriam Hospital, Weight Control and Diabetes Research Center, Providence, RI, 02903, USA. jlillis@lifespan.org.
Background:
Novel strategies to help adults with overweight/obesity increase motivation for becoming active are needed. This single-arm trial aimed to test the feasibility, acceptability, and preliminary efficacy of a 4-h acceptance and commitment therapy (ACT)-based workshop intervention for increasing moderate-to-vigorous physical activity (MVPA) among insufficiently active adults with overweight/obesity.
Methods:
Participants (N = 41) received a 1-day 4-h ACT workshop followed by weekly e-mails and monthly phone calls for 3 months. The primary outcome was change in accelerometer-measured MVPA minutes/day at 3 and 6 months. Process variables (i.e., autonomous motivation, PA acceptance) through which the ACT intervention was hypothesized to increase MVPA were assessed via questionnaires.
Results:
Participants completed 91% of phone calls and 75% of e-mail surveys. Acceptability ratings were > 4.5 out of 5 for "understandable," "useful," and "intent-to-use" on all intervention components. Participants on average achieved significant increases in bouted and total MVPA at 3 months that were maintained at 6 months. Participants also reported significant increases in physical activity acceptance and autonomous motivation, the latter of which related to MVPA changes.
Conclusion:
Results support the feasibility and acceptability of the ACT workshop intervention for promoting MVPA changes among insufficiently active adults with overweight/obesity. Rigorous testing of this approach as a low-intensity standalone or add-on intervention to increase MVPA is warranted.

