Table 1 Subject characteristics, exercise capacity and muscle strength

Age (years)

10.2

8.7

12.6 (2.6)

Weight (kg)

33 (SD-score 0)

25 (SD-score -1)

42.6 (6.5) (SD-score 0.01)

Height (cm)

143 (SD-score 0)

133 (SD-score 0)

154.6 (10.6) (SD-score -0.4)

W_peak (Watt)

115

70

145 (70)

HR_peak (b·min^-1)

195

195

185 (5)

RER_peak

1.27

1.25

1.22 (0.11)

VO_2peak (L·min^-1)

1.4 (SD-score -1.5)

1.2 (SD-score -1)

1.5 (0.46) (SD-score -1.6)

VO_2peak (ml·kg^-1·min^-1)

42.8 (SD-score -1.65)

50.2 (SD-score 0.06)

35.3 (5.3) (SD-score -2.17)

Peak blood lactate 3 min after the exercise test (mmol·l^-1)

7.3

6.0

6.5 (3.6)

Quadriceps muscle strength (N)

207 (SD-score 0.2)

156 (SD-score 0.8)

NM