Ventilatory responses at submaximal exercise intensities in healthy children and adolescents during the growth spurt period: a semi-longitudinal study.

Purpose: To identify the changes of ventilation ([Formula: see text] _E ), tidal volume (V _T ) and respiratory frequency (fr) at different incremental step test intensities during maturation of children and adolescents.
Methods: A semi-longitudinal study was conducted on 68 healthy untrained boys and girls aged 11-17 years. The subjects were separated into three distinct age groups. [Formula: see text] _E , V _T and fr parameters were evaluated annually during 3 years by modifying incremental step test intensities according to ventilatory threshold (V _Th ) level (30, 60 and 90% of [Formula: see text]O _2max ). Absolute and relative values of ventilatory responses were analyzed and compared according to age and developmental phase.
Results: (1) Height, weight, lean body mass and vital capacity increased significantly from 11 to 17 years of age. (2) [Formula: see text]O _2max , [Formula: see text] _E , and V _T increased during maturation even when exercise intensity changed, especially from 11 to 15 years of age. On the other hand, fr showed a decreasing trend.
Conclusion: Increases of V _T are the main reason for [Formula: see text] _E increases during maturation of children. fr decreased independently of total body mass during maturation. [Formula: see text] _E .kg ^-1 was stable despite intensity variations. V _T .kg ^-1 increased significantly from 11 to 15 years then stabilized at 17 years. Lean body mass seems to explain the evolution of V _T .kg ^-1 during maturation.
(© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)