Table 1.

Operationalisation of the SCT Constructs relevant to this study

Module 1
Strategy	SCT construct	Tailoring variables
Advice for meeting the PA guidelines	Self-efficacy	PA status PA level prior to pregnancy
Information about the beneficial outcomes of PA, exercise during pregnancy guidelines, resistance-based exercise guidelines and stretching	Outcome expectations	Outcome expectancies (outcomes valued by individual)
Advice and information on BMI classifications	Self-efficacy Behavioural capability Outcome expectations	Behavioural capability Outcome expectancies (outcomes valued by individual)
Advice on exercise intensity	Self-efficacy	PA status Current PA level
Advice on exercising safely	Self-efficacy Behavioural capability Outcome expectations	Behavioural capability Outcome expectancies (outcomes valued by individual)
Action planning	Self-efficacy Self-control and performance	PA status PA preference
Module 2
Feedback on PA performance	Self-efficacy Self-control and performance Reinforcement	PA status PA progress since M1
Advice on overcoming possible barriers to exercise during pregnancy	Environment Self-efficacy Self-control and performance	Self-discipline Time Health/illness Tired and exhausted Motivation Social Support Knowledge Environment
Action planning	Self-efficacy Self-control and performance	Goal setting behaviour after M1 PA status
Module 3
Strategy	SCT construct	Tailoring variables
Feedback on PA performance	Self-efficacy Self-control and performance Reinforcement	PA status PA progress since M1 and M2
Advice and tips on increasing social support to exercise during pregnancy	Environment Self-efficacy Self-control and performance	Partner Family and Friends Work colleagues
Action planning	Self-efficacy Self-control and performance	Goal setting behaviour after M1 and M2 PA status
Module 4
Feedback on PA performance	Self-efficacy Self-control and performance Reinforcement	PA status PA progress since M1, M2 and M3
Reminder on Exercise during pregnancy guidelines and recommendations	Self-efficacy Self-control and performance Reinforcement	PA status PA progress since M1, M2 and M3
Action planning	Self-efficacy Self-control and performance	Goal setting behaviour after M1, M2 and M3 PA status