The Effect Of Targeted Email Messages On E-monitoring Physical Activity Adherence

PURPOSE: Electronic monitoring (e-monitoring) adherence is the consistent tracking of physical activity (PA) with electronic devices and may be improved by targeted messages, especially among less experienced individuals. We observed the impact of targeted emails on e-monitoring adherence by PA status (beginners vs. non-beginners) during Desire2Move (D2M), an annual eHealth program that promotes PA among university employees in a team-based competition. METHODS: In 2024, 282 employees (74.8% female) from 19 departments registered for D2M, and most were non-beginners (78.7%; met PA guidelines and previously participated in D2M). Participants were assigned to teams based on department affiliation and logged daily PA minutes for eight weeks using approved mobile apps. Each participant’s PA minutes contributed to their team's total and the team with the greatest final average PA minutes won the competition. Using a 2 x 2 within-subjects cross-over design, teams were randomized to receive either targeted messages (TM) that addressed common logging issues or no messages (CON) during weeks 2-4. Participants were then crossed over to the other condition during weeks 5-7. Participants with no PA minutes for the first four weeks were excluded from analyses. Weekly e-monitoring adherence was coded as 0 (no minutes) or 1 (some minutes) and summed to create a total score for each condition (Range 0-3). RESULTS: Shapiro-Wilk tests revealed non-normal distributions for e-monitoring adherence in both conditions (N = 248; ps < .001). A Mann-Whitney U test showed a significant group difference in e-monitoring adherence by PA status for the CON condition, U = 5591.00, p = .003, with greater adherence among non-beginners (Mrank = 129.54) than beginners (Mrank = 101.76). No significant group difference was found for the TM condition (p = .076). CONCLUSION: Without weekly targeted email messages, non-beginners had better e-monitoring adherence than beginners. Understanding techniques that enhance e-monitoring adherence not only impacts team-based outcomes, but also facilitates a more thorough evaluation of the effectiveness of D2M for promoting PA of individual employees. Despite analytical limitations, these results are consistent with previous findings and improve our understanding of eHealth components.