Exercise capacity and muscle fatiguability alterations following a progressive maximal exercise of lower extremities in children with cystic fibrosis

Exercise performance in children and adolescents with cystic fibrosis with and without abnormal glucose tolerance: a single center cross-sectional study

BACKGROUND

Abnormal glucose tolerance (AGT) in cystic fibrosis (CF) affects lung function and clinical parameters, including aerobic fitness. However, its effects on physical activity level (PAL), anaerobic power (AP), and muscle strength (MS) in children and adolescents are unknown.

PURPOSE

To investigate aerobic fitness, PAL, AP, and MS in pediatric patients with mild-to-moderate CF and AGT.

METHODS

The study included children and adolescents with CF aged 10-18 years. Participants underwent a pulmonary function test, quadriceps, and handgrip MS measurement, vertical jump test to assess AP, and six-minute walk test (6MWT) to assess aerobic fitness. Bouchard's Three-Day Physical Activity record was used to determine PAL.

RESULTS

Height z-score (p = .006), 6MWT (p = .024), handgrip (p = .028), quadriceps MS (p = .044), and AP (p = .036) were significantly lower in AGT (n = 21) than normal glucose tolerance (NGT) (n = 19). In the AGT group, glycosylated hemoglobin (HbA1c) was significantly associated with forced expiratory volume in one second (FEV1) (p = .046). 6MWT distance (6MWD) was associated with height (p = .008), FEV1 (p = .001), forced vital capacity (FVC) (p = .001), forced expiratory flow from 25% to 75% (FEF25-75%) (p = .030), handgrip MS (p = .012), and PAL (p = .034). After adjusting for height and FEV1, the groups had similar 6MWD, MS, and AP (p > .05); also, insulin was associated with MS and AP but not with 6MWT or quadriceps MS.

CONCLUSION

Measures of aerobic fitness, MS, and AP are lower in AGT, but after adjusting for height and FEV1, aerobic fitness, MS, and AP do not show substantial differences. Insulin sensitivity and resistance are associated with MS and AP.

"Test-retest reliability and minimal detectable change in TGlittre-P test in children and adolescents with cystic fibrosis"

OBJECTIVE

to provide test-retest reliability for the TGlittre-P in children and adolescents with cystic fibrosis (CFG) and healthy controls (HCG), to establish the minimal detectable change for time in TGlittre-P and comparing the performance in the TGlittre-P test between these populations.

METHOD

A cross-sectional study evaluated 36 children and adolescents aged 6 to 13. Anthropometric and spirometric evaluation was performed, as well as, on the same day, two TGlittre-P tests with a 30-minute interval between them.

RESULTS

TGlittre-P time test-retest reliability was excellent for both groups (CFG: intraclass correlation coefficient [ICC] = 0.849, p < 0.001 and HCG: ICC = 0.913, p < 0.001). As concerning absolute reliability, the time spent presented a small variability with a standard error of measurement of 8.4 s (s) to CFG and 5.3 s to HCG. The minimal detectable change at 95% confidence level (MDC95) was 23.2 s and 14.6 s, respectively. There was no difference between the groups regarding performance in the TGlittre-P test (CFG 179.1 s ± 25.7 s vs. HCG 174.7 s ± 22.3 s) p = 0.589.

CONCLUSION

The TGlittre-P is a reliable tool in children and adolescents with CF and healthy controls. The TGlittre-P appears not to be sensitive enough to discriminate a group of children and adolescents with mild cystic fibrosis from healthy counterparts.IMPLICATIONS FOR REHABILITATIONTGlittre-P is a multitasking test that has been used to assess the functional capacity of children and adolescents with chronic diseases.TGlittre-P has excellent reliability in children and adolescents with and without CF.TGlittre-P differences time greater than 12% could indicate changes in the functional capacity of children and adolescents with CF.Other functional capacity tests may be preferred to detect continuous increases in functional capacity through rehabilitation or training, whether children and adolescents obtain performance values close to 100% of predicted.

Exercise and Cystic Fibrosis

Cystic fibrosis (CF) is an autosomal recessive, inherited congenital disease caused by the mutation of the family autosomal CF gene, with cumulative exocrine secretion characterized by inflammation, tracheal remodeling, and mucus accumulation. With the development of modern medical technology, CF patients are living longer lives and receiving more and more treatments, including traditional drugs, physical therapy, and gene therapy. Exercise is widely used to prevent and treat metabolic diseases such as cardiovascular diseases, obesity, diabetes, and metabolic syndrome. Regular exercise is beneficial to aerobic capacity and lung health. Exercise therapy has been of great interest since people realized that CF can be affected by exercise. Exercise alone can be used as an ACT (airway clearance technique), which promotes the removal of mucosal cilia. Exercise therapy is more easily accepted by any society, which helps to normalize the lives of CF patients, rather than placing a psychological burden on them. In this chapter, we will review the latest research progress about exercise in CF.

Exercise Physiology Across the Lifespan in Cystic Fibrosis

Cystic fibrosis (CF), a severe life-limiting disease, is associated with multi-organ pathologies that contribute to a reduced exercise capacity. At present, the impact of, and interaction between, disease progression and other age-related physiological changes in CF on exercise capacity from child- to adult-hood is poorly understood. Indeed, the influences of disease progression and aging are inherently linked, leading to increasingly complex interactions. Thus, when interpreting age-related differences in exercise tolerance and devising exercise-based therapies for those with CF, it is critical to consider age-specific factors. Specifically, changes in lung function, chronic airway colonization by increasingly pathogenic and drug-resistant bacteria, the frequency and severity of pulmonary exacerbations, endocrine comorbidities, nutrition-related factors, and CFTR (cystic fibrosis transmembrane conductance regulator protein) modulator therapy, duration, and age of onset are important to consider. Accounting for how these factors ultimately influence the ability to exercise is central to understanding exercise impairments in individuals with CF, especially as the expected lifespan with CF continues to increase with advancements in therapies. Further studies are required that account for these factors and the changing landscape of CF in order to better understand how the evolution of CF disease impacts exercise (in)tolerance across the lifespan and thereby identify appropriate intervention targets and strategies.