Comparison of the Effect of Different Inspiratory Loads on Diaphragmatic Function in Healthy Individuals

This pilot study aims to evaluate how the diaphragm responds to different inspiratory muscle training loads using ultrasound in healthy individuals. The observational, cross-sectional research seeks to determine whether ultrasound measurements of diaphragm movement and thickness can more effectively guide load prescription, thereby optimizing the benefits of inspiratory training. Twenty healthy participants, of both sexes, aged 18 to 35 years, will be recruited through outreach at the Faculty of Physiotherapy at the University of Vigo. The assessment will include spirometry, maximum inspiratory pressure (MIP) measurement, and ultrasound evaluations of the diaphragm at various loads (10%, 30%, 50%, and 70% of the MIP). Data will be analyzed to understand how diaphragm mobility, thickness, and contraction velocity vary according to load, with the goal of improving training prescription and adjustment. The study adheres to the ethical principles of the Declaration of Helsinki and ensures strict confidentiality and participant anonymity. The results will contribute to the understanding of non-invasive diaphragm assessment and its role in enhancing respiratory and physical performance.