Do Children With Cystic Fibrosis Differ in Muscle Endurance? A Comparative Study

Cystic fibrosis (CF) is an autosomal recessive genetic disease characterized by the involvement of exocrine glands, resulting from a disorder in the synthesis or function of the Cystic Fibrosis Transmembrane Regulator (CFTR) protein. The CFTR protein is responsible for ion and water transport in the cell epithelium. Dysfunction of this protein causes the secretion produced to be deficient in water. Viscous secretion, which is difficult to remove from its environment, causes permanent damage to many organs and systems such as the lungs, pancreas, hepatobiliary system and reproductive system. Respiratory failure due to CF lung disease is the most important cause of morbidity and mortality. The basic mechanism in the pathophysiology of CF lung disease is chronic inflammation and recurrent infections that occur as a result of the disruption of mucociliary clearance by sticky secretions. This vicious cycle causes obstruction in the airways and leads to progressive losses in respiratory functions. The decrease in respiratory functions; loss of muscle strength, reduced functional capacity, physical inactivity and reduced quality of life. There are limited studies in the literature comparing the respiratory muscle strength, respiratory muscle endurance and lower extremity muscle endurance of children with CF with their healthy peers. However, there is no study evaluating the core muscle endurance of children with CF. This study aims to compare the respiratory muscle strength, respiratory muscle endurance, core muscle endurance and lower extremity muscle endurance in children with CF and their healthy peers.