Table 2.

Behaviour change techniques included in the app/exercise programme

Cluster	BCT	App/exercise programme
1. Goals and planning	1.1. Goal-setting behaviour	Goal set to three weekly virtual group exercise sessions, and as many sessions of individual exercises as they could per week in addition. Minimum 15-min sessions, of moderate to high intensity.
	1.2. Problem solving	Advised to perform an alternative indoor activity if the weather was too harsh/medical conditions did not allow outdoor walking.
	1.4. Action planning	Scheduled virtual group exercises. (Frequency, minimum duration, day and time, intensity, type of activity).
2. Feedback and monitoring	2.1. Monitoring of behaviour by others without feedback	The virtual group members see each other’s activity status.
	2.3. Self-monitoring of behaviour	Self-recording of individual exercises in the diary. IMA values. Keeping their virtual group activity status up to date.
4. Shaping knowledge	4.1. Instruction on how to perform a behaviour	The follow-along exercise video. The participants were advised at the start-up meeting on walking speed for health benefits and on how to control their dyspnoea.
5. Natural consequences	5.1. Information about health consequences	Emphasis of the health benefits of a physically active lifestyle at the start-up meeting.
6. Comparison of behaviour	6.1. Demonstration of behaviour	The follow-along exercise video. The outdoor walk with the physiotherapist at the start-up meeting.
7. Associations	7.1. Prompt/cues	Status updates from peers in the virtual group at the time of performance.
9. Comparison of outcomes	9.1. Credible source	At the start-up meeting, a pulmonary rehabilitation physiotherapist and a lung nurse emphasized the importance of physical activity.
10. Rewards and threats	10.3. Non-specific reward	The participants received visual rewards on the wallpaper.
12. Antecedents	12.5. Adding objects to the environment	The tablet on its table stand.