Table 1.

Stay Strong components by trial arm.

Component	SSa arm	SS+Coaching arm	Intensity	Duration	Mode
Objective physical activity monitoring (Fitbit Charge 2 and data visualizations within SS)	✓	✓	Fitbit worn daily, and data syncing at least 1/week	1 year	Fitbit worn on wrist; data visualizations available within SS app
Weight self-monitoring (scale and weight data visualizations within SS)	✓	✓	Weight measured weekly with data syncing at least 1/week	1 year	Data visualizations available within SS app
Administrative message reminders (reminders for Fitbit and weight scale syncing, adverse event reporting, and data assessments)	✓	✓	One message less than 230 characters	As needed over 1 year	Push notification on phone
Automated personalized goal setting		✓	Weekly, based on previous weeks’ physical activity data	1 year	Abbreviated phone push notification and message with image within SS app
Automated messages: nonpersonalized		✓	1 message up to 225 characters, 3/week	1 year	Abbreviated phone push notification and full message with visual image within SS app
Automated messages: personalized based on self-reported barriers		✓	1 message up to 225 characters, 3/week	1 year	In-app and smartphone notification with image
Telephone-based lifestyle coaching		✓	Up to 30 min	2 calls plus an optional 3rd call in the first 9 weeks	Telephone

^aSS: Stay Strong.