Reference Values for Inspiratory Muscle Endurance in Healthy Children and Adolescents.

To generate reference values for two inspiratory muscle endurance (IME) protocols in healthy children and adolescents.This is an observational, cross-sectional study, in healthy children and adolescents from 4 to 18 years of age. Weight, height, maximal inspiratory pressure (MIP) and IME were measured using two protocols. A fixed load of 30% of MIP with a 10% increment every 2 minutes was used in the incremental threshold loading protocol. As for the maximal loading protocol, a fixed load of 70% of MIP was used and the time limit (Tlim) achieved until fatigue was measured.A total of 462 participants were included, 281 corresponding to the incremental loading protocol and 181 to maximal loading. There were moderate and positive correlations between IME and age, MIP, weight and height in the incremental threshold loading. However, the regression model demonstrated that MIP and age were the best variables to predict the IME. Otherwise, weak and positive correlations with age, weight and height were found in the maximal loading. Only age and height influenced endurance in the regression model. The predictive power (r2) of the incremental threshold loading protocol was 0.65, while the maximal loading was 0.15. The reproducibility measured by the intraclass correlation coefficient (ICC) was higher in the incremental loading (0.96) compared to the maximal loading test (0.69).IME in healthy children and adolescents can be explained by age, height and MIP. The incremental threshold loading protocol showed more reliable results and should be the model of choice to evaluate IME in the pediatric age group

Effects of obesity on lung volume and capacity in children and adolescents: a systematic review

Abstract Objective: To assess the effects of obesity on lung volume and capacity in children and adolescents. Data source: This is a systematic review, carried out in Pubmed, Lilacs, Scielo and PEDro databases, using the following Keywords: Plethysmography; Whole Body OR Lung Volume Measurements OR Total Lung Capacity OR Functional Residual Capacity OR Residual Volume AND Obesity. Observational studies or clinical trials that assessed the effects of obesity on lung volume and capacity in children and adolescents (0-18 years) without any other associated disease; in English; Portuguese and Spanish languages were selected. Methodological quality was assessed by the Agency for Healthcare Research and Quality. Data synthesis: Of the 1,030 articles, only four were included in the review. The studies amounted to 548 participants, predominantly males, with sample size ranging from 45 to 327 individuals. 100% of the studies evaluated nutritional status through BMI (z-score) and 50.0% reported the data on abdominal circumference. All demonstrated that obesity causes negative effects on lung volume and capacity, causing a reduction mainly in functional residual capacity in 75.0% of the studies; in the expiratory reserve volume in 50.0% and in the residual volume in 25.0%. The methodological quality ranged from moderate to high, with 75.0% of the studies classified as having high methodological quality. Conclusions: Obesity causes deleterious effects on lung volume and capacity in children and adolescents, mainly by reducing functional residual capacity, expiratory reserve volume and residual volume

Modified linear workload device.

<p>Modified linear workload device.</p

Bland-Altman plots showing the individual differences between both evaluations of the incremental threshold loading (A) and maximal loading (B) protocols, in relation to the mean values of IME.

<p>The solid lines indicate the mean differences between the measurements and the dotted lines indicate the 95% limits of agreement.</p

Characteristics of the subjects included.

<p>Characteristics of the subjects included.</p

Correlations between IME, evaluated through the incremental threshold loading protocol, and age (A) and MIP (B) and between IME, evaluated through the maximal loading protocol, and age (C) and height (D).

<p>Correlations between IME, evaluated through the incremental threshold loading protocol, and age (A) and MIP (B) and between IME, evaluated through the maximal loading protocol, and age (C) and height (D).</p

Multiple linear regression models for IME in both protocols.

<p>Multiple linear regression models for IME in both protocols.</p