TNF and juvenile idiopathic arthritis: The maximal fat oxidation rate during exercise was lower in JIA children untreated by TNF blockade (134.3 ± 45.2 mg.min− 1) when compared to the controls (225.3 ± 92.9 mg.min− 1, p = 0.007); but was higher in JIA children under TNF blockade (163.2 ± 59.0 mg.min− 1, p = 0.31) when compared to JIA children untreated by TNF blockade.