Table 1 Summary of perceived personal, social and environmental measures based on confirmatory factor analysis

Enjoyment-Competence scale (response format 1–3)

Brustad⁽¹⁹⁹³⁾

Subscale Enjoyment

Harter⁽¹⁹⁷⁸⁾

I have more fun playing games and sports than doing other things

Playing games and sports is the thing I like to do best.

I wish I could play more games and sports than I get chance to.

I usually prefer to watch rather than play games

I really like doing PE at school.

Subscale Competence

I feel that I am better than most other kids my age at games and sports.

I feel really bad when I get out of breath from running around

I feel that I can easily keep up with other kids when playing games and sports.

Outcome expectations scale (response format 1–3)

Trost et al⁽¹⁹⁹⁷⁾

Subscale Social Expectations: If I were to exercise most days it would....

Be fun

Help me make new friends

Help me be with my friends more

Help me look good to others

Subscale Functional Expectations: If I were to exercise most days it would....

Get or keep me in shape

Make me better in sports

Help me be healthy

Help me control my weight

Give me energy

Perceived social support scale (response format 1–4)

Sallis et al.⁽¹⁹⁹⁹⁾

Subscale Parental Support: How often does your mum or dad...

Take you to exercise or play sports

Watch you take part in exercise or sports

Exercise or play sports with you

Subscale Parental Encouragement: How often does your mum or dad...

Tell you to exercise or play sports

Tell you that exercise is good for your health

Subscale Peer support

How often do your friends exercise or play sports with you?

How often do you ask your friends to play out with you?

How often do your friends ask you to play out with them?

Subscale Teacher support: How often does your teacher....

Items for teacher support generated through pilot study

Talk about exercise in lessons

Organise or play games with you apart from PE

Tell you to exercise or play sports

Social-physical environment scale (response format 1–3)

Sallis et al.⁽¹⁹⁹⁹

Subscale opportunity:

Trost et al⁽¹⁹⁹⁷⁾

It is safe to walk or play alone in my neighbourhood during the day.

There are other children near by home to go out and play with

There is somewhere at home I can go out and play

Subscale Facility:

There are playgrounds or parks close to my home where I can play

At school there are playgrounds or fields where I can run around

Subscale License:

I always have to tell my parents where I am when I go out

If I am going out I always have to be back by a certain time