Reference Values for Inspiratory Muscle Endurance in Healthy Children and Adolescents

Cristhiele Taís Woszezenki; João Paulo Heinzmann-Filho; Fernanda Maria Vendrusculo; Taila Cristina Piva; Isadora Levices; Márcio Vinícius Fagundes Donadio

doi:10.1371/journal.pone.0170696

Reference Values for Inspiratory Muscle Endurance in Healthy Children and Adolescents

PLoS One. 2017 Jan 25;12(1):e0170696. doi: 10.1371/journal.pone.0170696. eCollection 2017.

Authors

Cristhiele Taís Woszezenki¹, João Paulo Heinzmann-Filho^{1

2}, Fernanda Maria Vendrusculo^{1

2}, Taila Cristina Piva³, Isadora Levices³, Márcio Vinícius Fagundes Donadio^{1

2

3}

Affiliations

¹ Graduate Program in Pediatrics and Child Health, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brasil.
² Laboratory of Pediatric Physical Activity, Centro Infant, Institute of Biomedical Research, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brasil.
³ School of Nursing, Nutrition and Physiotherapy, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brasil.

Abstract

Aims: To generate reference values for two inspiratory muscle endurance (IME) protocols in healthy children and adolescents.

Materials and methods: 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.

Results: 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).

Conclusion: 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.

Publication types

Observational Study

MeSH terms

Adolescent
Child
Child, Preschool
Cross-Sectional Studies
Female
Humans
Male
Physical Endurance / physiology*
Reference Values
Reproducibility of Results
Respiratory Function Tests
Respiratory Muscles / physiology*

Grants and funding

JPH and CTW were supported by CAPES. TCP was supported by CNPq. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.