Table 2 Examples of motivational messages embedded in the start app based on need-supportive communication

Early (weeks 1–3)

Good effort for reaching your step count goal once last week. There are many ways you can increase your step count—organized walks, active commuting, planned social walks with family and friends, finding nature walks, becoming more active in day to day life. Our app includes some ideas of how you can increase your walking on more days of the week to reach your goals

Wow, you really smashed it last week by exceeding your weekly goal. That's amazing and testament to your commitment. Think about what worked for you last week to achieve this great result and see if you can leverage from that again this week

Mid (weeks 9–10)

It can be helpful to reflect on why you joined the START program (e.g., health benefits, fitness, friendships). Trying to walk more on most days of the week will help you achieve what is important to you. What might you do the same and what might you do differently this week to meet your goal on more days?

Way to go last week! You exceeded the weekly goal. What helped you to achieve this success last week? Take a moment to enjoy the feeling and use that image if you ever find yourself struggling to meet your step count goals. Next week's challenge will be to meet your step count goal on 5 days per week

Late (weeks 13–16)

What opportunities might there be this week to increase your steps? You might find it helpful to plan ahead, considering what works for you, and also what makes it enjoyable for you. Thanks for joining us as part of the START program. We hope you will benefit from the changes you’ve made in the last 16 weeks and plan ways to sustain your new active lifestyle

Well done on meeting your goal on 5 days last week! Thanks for joining us as part of the START program. We hope you will benefit from the changes you’ve made in the last 16 weeks and plan ways to sustain your new active lifestyle