Table 3 Simple associations between predictors and change in moderate and vigorous physical activity for weekdays and weekends

Biological and socio-demographic factors

Age (y)

0.22 (−0.01, 0.45)^#

0.02 (−0.22, 0.26)

0.20 (−0.21, 0.62)

−0.32 (−0.80, 0.16)

Sex (ref: boys)

−0.53 (−0.79, -0.27)^***

−0.03 (−0.04, -0.02)^***

−0.67 (−1.10, -0.24)^**

−0.64 (−1.06, -0.22)^**

BMI z-score

−0.03 (−0.14, 0.09)

0.02 (−0.06, 0.09)

−0.04 (−0.20, 0.13)

−0.27 (−0.44, -0.10)^**

Parent education (high vs. low)

−0.22 (−0.46, 0.01)^#

−0.23 (−0.47, 0.02)^#

−0.22 (−0.61, 0.17)

−0.01 (−0.32, 0.29)

IMD

−0.01 (−0.02, 0.01)

−0.01 (−0.01, 0.01)

0.016 (−0.01, 0.04)

0.17 (−0.01, 0.04)

Psychological factors

PA preference (high vs. low)

0.06 (−0.16, 0.28)

−0.04 (−0.23, 0.15)

0.56 (0.18, 0.93)^**

0.48 (0.15, 0.81)^**

SE for overcoming barriers (high vs. low)

0.09 (−0.11, 0.30)

−0.05 (−0.25, 0.15)

0.38 (0.008, 0.75)^*

0.11 (−0.23, 0.44)

SE for support seeking (high vs. low)

−0.03 (−0.27, 0.22)

0.02 (−0.21, 0.26)

−0.05 (−0.47, 0.37)

0.14 (−0.25, 0.54)

Personal barriers (high vs. low)

−0.05 (−0.26, 0.16)

0.10 (−0.08, 0.28)

−0.11 (−0.50, 0.27)

−0.23 (−0.57, 0.11)

Home PA equipment (high vs. low)

0.04 (−0.20, 0.28)

0.31 (0.08, 0.54)^**

−0.63 (−1.10, -0.17)^**

−0.28 (−0.66, 0.09)

Socio-cultural factors

Peer support (high vs. low)

0.17 (0.01, 0.33)^*

0.22 (0.05, 0.38)^**

0.35 (−0.013, 0.72)^#

0.25 (−0.12, 0.62)

Family encouragement

0.01 (−0.03, 0.06)

0.01 (−0.04, 0.05)

0.02 (−0.06, 0.10)

0.07 (−0.10, 0.14)^#

Family logistic support

0.03 (−0.02, 0.08)

0.01 (−0.06, 0.06)

0.18 (0.09, 0.27)^***

0.18 (0.08, 0.29)^***

Sedentary restrictions

0.01 (−0.04, 0.05)

0.03 (−0.01, 0.06)

0.02 (−0.05, 0.08)

−0.03 (−0.10, 0.03)

PA restrictions

0.01 (−0.06, 0.08)

0.01 (−0.05, 0.07)

−0.03 (−0.016, 0.10)

−0.05 (−0.17, 0.07)

Family cohesiveness

−0.01 (−0.02, 0.02)

−0.01 (−0.03, 0.01)

0.015 (−0.03, 0.05)

0.04 (−0.01, 0.07)^#

Freedom to play (yes vs. no)

−0.01 (−0.22, 0.20)

0.08 (−0.14, 0.30)

0.01 (−0.33, 0.35)

−0.27 (−0.57, 0.04)^#

Games console at home (yes vs. no)

0.32 (−0.01, 0.63)^#

0.06 (−0.04, -0.02)^***

−0.14 (−0.78, 0.50)

−0.02 (−0.61, 0.57)

Electronic equipment in bedroom (yes vs. no)

0.27 (0.02, 0.52)^**

0.15 (−0.04, 0.34)

0.13 (−0.29, 0.55)

0.12 (−0.32, 0.57)

Behavioural factor

Active Travel to school (active vs. passive)

0.10 (−0.13, 0.33)

0.06 (−0.11, 0.34)

0.06 (−0.31, 0.43)

−0.17 (−0.48, 0.14)

Environmental factors

Living in a cul de sac (yes vs. no)

−0.22 (−0.47, 0.02)^#

0.08 (−0.15, 0.30)

−0.17 (−0.55, 0.20)

0.06 (−0.27, 0.39)

Effective walkable area

−0.57 (−0.37, 0.23)

−0.49 (−1.09, 0.12)

−0.27 (−1.5, 0.97)

0.13 (−1.05, 1.30)

Woodland percentage (log%)

−0.05 (−0.17, 0.07)

0.04 (−0.06, 0.14)

0.04 (−0.14, 0.23)

0.15 (−0.02, 0.32)^#

Land use mix (Lower v. higher)

−0.28 (−0.51, -0.05)^**

−0.16 (−0.36, 0.04)

−0.31 (−0.68, 0.05)^#

0.11 (−0.26, 0.48)

Distance to green space (log km)

−0.01 (−0.14, 0.11)

−0.01 (−0.12, 0.10)

−0.08 (−0.26, 0.10)

−0.04 (−0.19, 0.12)

Distance to sport venue (log km)

0.05 (−0.06, 0.17)

0.04 (−0.05, 0.14)

0.14 (−0.09, 0.36)

0.07 (−0.12, 0.27)

Distance to school (log km)

−0.09 (−0.18, -0.01)^*

−0.10 (−0.18, -0.02)^**

0.06 (−0.09, 0.22)

0.03 (−0.16, 0.21)

Availability of parks (yes vs. no)

0.18 (−0.06, 0.43)

0.08 (−0.20, 0.36)

0.10 (−0.39, 0.59)

−0.05 (−0.57, 0.47)