Using an email intervention to successfully encourage twenty-something females to apply sunscreen before running outside. Shows that placing sunscreen by a female runner's sports bras can act as an effective secondary trigger.

1. DoesEmail + Sports Bra + Sunscreen = Habit? Kristy Allenby habits.stanford.edu

2. How do you create a sunscreen habit? Auto-matic

3. How did this intervention work? This intervention encouraging habitual sunscreen usage in 20-something female runners who don’t use sunscreen when running outside. The technology is a daily email containing: The technology sets up a trigger (sunscreen by the sports bra) that the runner sees right before going outside to run. Weather report Reminder to place sunscreen near sports bra Running tip to keep participants interested in opening emails

4. The Intervention Step-by-Step Susan, a grad student, checks her email when she first wakes up. She has an email with the day’s weather and a reminder to put her sunscreen by her sports bra in case she runs outside that day. The email and visual cue reminds Susan to check to make sure her sunscreen is next to her sports bra. Susan applies sunscreen before her run. When she gets dressed for her run later that day, she sees the sunscreen next to her sports bra and remembers to put it on. This is the trigger.

5. Why target female 20-something women? Twenty-somethings check email every morning Twenty-somethings use internet to check the weather before running outside Female runners need to put on a sports bra before running Female twenty-somethings are more likely to care about sun damage and have latent motivation to use sunscreen due to age and outdoor activity, which can be easily tapped by a trigger

6. Intervention Results 0% 55% More than half of participants reported using sunscreen when they ran outside during the email intervention. These were women who did not use sunscreen previously when running outside!

7. Did this become a habit? 60% A week after the intervention ended, over half of participants reported using sunscreen when they ran outside. The intervention even worked for a participant who didn’t use sunscreen at all during the email campaign – she habitually used sunscreen the week after it ended!

8. What was most useful in habit creation? Participants rated both the email and the sunscreen by the sports bra as effective triggers Putting the sunscreen by the sports bra was, on average, a more useful trigger than the email Sports bra sunscreen reminder: 3.8* Daily email: 3.4* But…a double-trigger inspired more action than just one trigger The email campaign proved to be a significant motivator for participants who weren’t influenced by putting sunscreen by the sports bras * Rated on a scale of 1 (not useful) to 5 (very useful)

9. Takeaways Pairing physical reminders with technological reminders helped a greater number of participants change their behavior. The intervention inspired longer-term behavior change, which can lead to an automated habit of applying sunscreen before an outdoor run.