Ventilatory control during exercise in normal children
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Updated: Oct 29, 2026
Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
1Department of Pediatrics, Nagoya University School of Medicine, Japan.
Insights
Younger children increase ventilation more to eliminate carbon dioxide during exercise, maintaining a lower arterial PCO2 (PaCO2) set point than older children. This age-related difference in respiratory control is crucial for exercise studies.
Area of Science:
- Pediatric Exercise Physiology
- Respiratory Control Mechanisms
- Pulmonary Function Testing
Background:
- Understanding how children's respiratory systems adapt during physical exertion is vital for assessing their health and performance.
- Previous research has not fully elucidated the age-related changes in respiratory control during exercise in pediatric populations.
Purpose of the Study:
- To investigate the relationship between age and respiratory control during exercise in children.
- To determine if gender influences age-related respiratory control during exercise.
- To analyze specific ventilatory parameters at different exercise intensities.
Main Methods:
- Eighty children (6.4-17.6 years) underwent symptom-limited treadmill exercise tests using the Bruce protocol.
- Respiratory parameters including minute ventilation (VE), carbon dioxide production (VCO2), effective alveolar ventilation (VA), pulmonary dead space (Vd), tidal volume (Vt), and arterial PCO2 (PaCO2) were measured.
- Data were analyzed for correlations with age and gender, with a focus on ventilatory anaerobic threshold and regression slopes (deltaVE/deltaVCO2, deltaVA/deltaVCO2).
Main Results:
- At rest and peak exercise, key respiratory ratios (VE/VCO2, VA/VCO2, Vd/Vt) and PaCO2 did not correlate with age.
- At the ventilatory anaerobic threshold, PaCO2 significantly increased with age, while VA/VCO2 decreased.
- The slopes of VE/VCO2 and VA/VCO2 relationships with exercise intensity significantly decreased with age, with no gender differences observed.
Conclusions:
- Younger children exhibit a higher ventilation relative to carbon dioxide production during exercise compared to older children.
- This age-dependent respiratory strategy helps maintain a slightly lower PaCO2 set point in younger children.
- These findings highlight the importance of considering age-related changes in ventilatory control when interpreting exercise responses in children.
Abstract:
We investigated the relation between age and respiratory control during exercise in 80 children aged 6.4-17.6 y (42 male, age, 11.6 +/- 3.3 y; body weight, 41.3 +/- 14.7 kg; and 38 female, age, 12.6 +/- 2.7 y; body weight, 42.5 +/- 9.3 kg). Exercise tests were performed on a treadmill after a standard symptom-limited Bruce protocol. Data were analyzed separately for boys and girls. At rest and at peak exercise, the ratio of minute ventilation to carbon dioxide production (VE/VCO2), the ratio of effective alveolar ventilation to carbon dioxide production (VA/VCO2), the ratio of pulmonary dead space to tidal volume (Vd/Vt), and arterial PCO2 (PaCO2) were not correlated with age. At the exercise intensity of ventilatory anaerobic threshold, the PaCO2 increased, and the VA/VCO2 decreased, significantly with age, whereas the Vd/Vt was not related to age. Linear regression analysis demonstrated that the slope of the relationship between VE and VCO2 (deltaVE/deltaVCO2) and the slope of the relationship between VA and VCO2 (deltaVA/deltaVCO2) decreased with age. There were no gender differences in the regression slopes and the intercepts of the relationships. Results show that younger children breathe more during exercise to eliminate a given amount of CO2 to keep PaCO2 set point slightly but significantly lower than older children. This age dependence must be considered in investigating ventilatory control during exercise in children.
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