The assessment of forearm oxygen consumption (VO₂) and forearm blood flow (FBF) by means of near infrared spectroscopy has become widespread in adults, whereas in children and adolescents no data are available. The aim of the present study was to analyze VO₂ and FBF in healthy children and adolescents. Methods: In a prospective cohort study, 20 male and 20 female healthy children and adolescents were investigated. The measurements of VO₂ and FBF were performed by means of near infrared spectroscopy in combination with the venous occlusion method. Results: Mean VO₂ was 0.08 ± 0.04 ml 100 g⁻¹ min⁻¹ in male and 0.09 ± 0.05 ml 100 g⁻¹ min⁻¹ in female subjects. Mean FBF was 1.95 ± 1.25 ml 100 g⁻¹ min⁻¹ in male and 1.82 ± 0.98 ml 100 g⁻¹ min⁻¹ in female subjects. No significant difference was found between male and female subjects. A significant negative correlation of VO₂ and FBF to age was observed in both groups. Conclusion: In the present study we were able to show that VO₂ and FBF decreased with increasing age in children and adolescents without significant differences between male and female subjects.