Abstract Rationale To determine 1) whether change in physical activity (PA) is impacted by active engagement in an online community forum during participation in a digital fitness program, and 2) if accuracy of self-reported physical activity (PA) changes over time among individuals with the rare, female-predominant, cystic lung disease lymphangioleiomyomatosis (LAM) Methods A secondary analysis was performed for n = 25 women with LAM (mean age 53±13 years) enrolled in the novel digital fitness program called ‘LAMFit’. After a 2-week run-in period, LAMFit participants received a customized digital fitness program for 24 weeks, consisting of 4 times/week continuous aerobic exercise 30 to 45 minutes, and 2 times/week resistance training. LAMFit included personalized goal setting for daily minutes of moderate-to-vigorous physical activity and for adherence to the exercise program. Wrist-worn accelerometry objectively measured PA and metabolic equivalents (METs) of exercise. Maintenance of PA behaviors was assessed post-intervention for 2 weeks and compared to Baseline. Self-report of PA was also collected at these timepoints, via the International Physical Activity Questionnaire - Short Form (IPAQ-SF). An optional online LAMFit community forum facilitated sharing of insights into overcoming barriers related to exercise and LAM and celebration of group activity goal achievements. Pearson correlations examined relationships between 1) self-reported and objectively measured PA before and after the intervention to estimate the impact of learning on the accuracy of self-report over time, and 2) active engagement on the LAMFit community forum (defined as number of replies to posts) and change in mean daily moderate intensity PA and weekly step count. Results PA obtained by self-report (IPAQ-SF) more closely aligned with PA objectively measured by wrist-worn accelerometry (mean MET*mins) after the 24-week home exercise program (r = 0.72, p = 0.001) compared to at Baseline (r = 0.46, p = 0.04). Active engagement on the LAMFit community forum was associated with a greater change from Baseline in amount of accelerometry-measured moderate PA (r = 0.54, p = 0.025) and steps per week (r = 0.61, p = 0.016), compared to program participants that did not choose to engage. Conclusions Engagement in an online community forum positively impacted LAMFit’s effect on PA, suggesting an association between higher active community engagement and PA behavior change. An online community forum may be useful as a supplemental PA behavior change technique. A learning effect was observed in accuracy of self-reported habitual PA following the 24-week LAMFit exercise intervention, with self-reported values more closely reflecting objective values. This abstract is funded by: An Established Investigator Award from The LAM Foundation
Child et al. (2026) studied this question.