Changes in respiratory muscle pressure of healthy individuals with different levels of immersion in water: observational study

Abstract

Purpose: Understanding the physiological effects of immersion, particularly on pulmonary dynamics in healthy individuals is important to predict and interpret the physiological responds in unhealthy group. The aim of our study is to evaluate the inspiratory and expiratory muscle strength and cough strength in healthy individuals during water immersion at different water depths.Methods: A cross-sectional study was conducted in 24 healthy individuals with the mean age 20.0 years. Respiratory muscle strength test and cough force were tested on dry land and in pool at iliac crests, xiphoid appendix of the sternum and clavicles levels. Measurements were randomized at each level. The Friedman test was used for repeated measures with Wilcoxon signed ranks test with Bonferroni correction was applies to compare the variables.Results: A significant difference between dry land and immersion in water of different levels for MEP (p=0.001) and PEF (p= 0.015). Multiple comparisons showed no difference between levels in PEF (p<0.001), whereas MEP values measured in clavicles level was significantly higher than both dry land and iliac crest level (p<0.0125).Conclusion: Clavicle level immersion alters respiratory muscle strength when compared with the values measured out of the water and immersed at the iliac crest level in healthy individuals.