Effects of Inspiratory Muscle Training Added to a Swimming Program in Children with Asthma

Background and Objectives: Asthma remains one of the most common chronic diseases in childhood, and despite advances in pharmacological management, its prevalence continues to rise globally. Physical activity, particularly swimming, has been proposed as a safe and beneficial form of exercise for asthmatic children due to the warm and humid environment that minimizes airway irritation. This study aimed to investigate the effects of adding inspiratory muscle training (IMT) to a structured swimming program on pulmonary function and asthma control in children with asthma. Materials and Methods: Thirty children with clinically diagnosed asthma, aged 8–11 years, were randomly assigned to either a swimming plus IMT group (n = 15) or a swimming-only control group (n = 15). Both groups participated in a 4-week supervised swimming program consisting of three 60-minute sessions per week. Inspiratory muscle training was integrated into the warm-up and cool-down phases for the experimental group. Pulmonary function parameters (FVC, FEV₁, FEV₁/FVC, PEF, MIP, MEP, MVV) and asthma control scores (Childhood Asthma Control Test [CACT]) were measured before and after the intervention. Statistical analyses were performed using repeated-measures ANOVA with significance set at p < 0.001. Results: Following the 4-week intervention, significant improvements were observed in all respiratory parameters and asthma control indices in both groups (p < 0.001). However, the swimming + IMT group showed substantially greater improvements in FEV₁ (↑46.4%), MIP (↑37.2%), MEP (↑42.6%), and CACT (↑69.5%) compared to the swimming-only group (FEV₁ ↑27.3%, MIP ↑10.3%, MEP ↑9.9%, CACT ↑30.1%). Effect sizes (Cohen’s d) were large across all primary outcomes, indicating a strong clinical impact of the combined intervention. Conclusions: The addition of inspiratory muscle training to a structured swimming program markedly enhances respiratory muscle strength, pulmonary function, and asthma control in children with mild-to-moderate asthma. These findings support incorporating IMT into aquatic exercise-based rehabilitation programs for pediatric asthma management.