Table 4 Direct and indirect intervention effects on general Health-related quality of life, intervention effects on potential mediators, effects of the mediators on general Health-related quality of life and the univariate mediation effects

β (95% CI)

β (95% CI)

β (95% CI)

estimate (95% CI)

n

Potential mediators

 VO_2peak (ml•kg•min^− 1)

−0.5 (− 3.2; 2.1)

0.3 (− 0.6; 1.1)

0.3 (− 6.5; 7.1)

− 0.3 (− 3.3; 0.8)

46

 Lower body muscle strength (N)

22.7 (− 21.6;67.0)

− 0.0 (− 0.0; 0.0)

−3.3 (− 10.4; 3.8)

−0.1 (− 2.6; 0.7)

50

 Upper body muscle strength (N)

−20.3 (− 48.6; 7.7)

0.0 (− 0.0; 0.1)

−2.6 (− 9.7; 4.6)

−0.5 (− 3.9; 0.5)

50

 Physical activity (cpm)

29.1 (−9.8; 68.0)

−0.0 (− 0.1; 0.1)

0.6 (− 9.4; 10.7)

−0.7 (− 8.5; 1.5)

33

 Fatigue

−1.2 (− 7.6; 5.1)

0.2 (− 0.1; 0.5)

−2.9 (− 10.1; 4.2)

−0.3 (− 3.7; 1.0)

49

 Depressive symptoms

0.2 (− 1.6; 2.0)

−1.4 (− 2.4; − 0.5)*

−3.5 (− 9.9; 3.0)

0.7 (−2.4; 3.6)

49

 Athletic competence

−1.5 (− 11.0; 8.1)

0.2 (0.0; 0.4)*

−4.2 (− 11.3; 3.0)

0.0 (− 2.8; 3.0)

46

 Global self-worth

− 0.3 (− 13.2; 12.6)

0.2 (0.0; 0.3)*

−5.2 (− 12.5; 2.2)

1.0 (− 1.2; 4.8)

46

 Behavior problems

1.1 (−5.1; 7.2)

−0.5 (− 0.9; − 0.1)*

0.6 (− 7.8; 8.9)

0.3 (− 6.7; 3.6)

30