Expiratory Muscle Training in Healthy Children: Randomized Clinical Trial

Introduction: There is currently a high prevalence of respiratory pathologies in preschool age. Respiratory muscle weakness is one of the main functional repercussions of the deterioration of lung function in children with respiratory disorders, as it can lead to intolerance to physical effort, worsening the subject's quality of life. An effective strategy to reverse this situation is through respiratory muscle training. Objective: The objective was to investigate the effect of expiratory muscle training on the respiratory capacity of healthy children. Methodology: A longitudinal and prospective randomized clinical trial was carried out at a State School in the interior of southern Brazil. Healthy subjects of both sexes, with an average age of six years, who did not have any declared respiratory comorbidity, were included. Subjects with any type of comorbidity were excluded, including a clinical history of asthma, bronchitis, pervasive developmental disorder, and neurogenic conditions. The subjects were evaluated pre- and post-intervention, in addition to being re-evaluated at a 3-month follow-up. Training followed, in both groups, the performance of 3 sets of 10 repetitions per week, for six weeks. The Water Group used PEP in Water Seal, while the Respiron Group used Respiron®. Results: 34 children were included and the total sample showed significant results in relation to respiratory capacity and respiratory muscle strength, both in the short term, medium and long term, in which all subjects showed improvement with statistical differences in these variables ( p= <0.001). This result shows that both devices are effective, but the statistical results showed no difference between them, making it impossible to say which device is more effective. Conclusion: The proposed physiotherapeutic protocol promoted improvements in children's respiratory strength and capacity, both in the short and long term.