Table 1 Description of each component of the transtheoretical model (TTM)

Stage of change

Pre-contemplation

No intention to engage in regular physical activity

Contemplation

Intend to engage in regular physical activity in next 6 months

Preparation

Immediate intentions and commitment to engage in regular physical activity

Action

Initiated engagement in regular physical activity in last 6 months

Maintenance

Maintained engagement of regular physical activity for longer than 6 months

Self-efficacy

Personal confidence towards physical activity commitment when: Tired/In a bad mood/Do not have time/On vacation/It is raining or snowing/Having respiratory symptoms*

Decisional balance

Pros

Perceived benefits of engaging in regular physical activity

Cons

Perceived barriers to engaging in regular physical activity

Cognitive processes of change

Increasing knowledge

Finding information on the benefits of physical activity and the current recommendations for physical activity

Being aware of risk

Concern for the risks of being physically inactive

Caring about consequences

Realising social and environmental benefits that physical activity has

Comprehending benefits

Assessing physical activity status and the values related to physical activity

Increasing healthy opportunities

Awareness, availability and acceptance by the individual of physical activity in the society

Behavioural processes of change

Substituting alternatives

Substituting inactive options for active options

Enlisting social support

Seeking out social support to increase and maintain physical activity

Rewarding oneself

Providing rewards for being more active

Committing oneself

Setting goals and making commitments for physical activity

Reminding oneself

Controlling factors that have a negative effect on physical activity to prevent relapse and using stimuli to increase physical activity level