Special Considerations and Perspectives for Exercise-Induced Bronchoconstriction (EIB) in Olympic and Other Elite Athletes

Exercise-Induced Bronchoconstriction in Children: A Comparison between Athletes and Non-Athletes

Exercise-induced bronchoconstriction (EIB) is a dysfunction of the respiratory tract consisting of transient airflow obstruction. This study is a retrospective analysis of two prospective studies concerning EIB symptoms in two adolescent populations. Our study group included 400 non-athletes and 101 athletes. Due to the similarity of indoor exercise conditions, an analysis was performed on the basis of where training took place. The study aims to assess the EIB prevalence in the following groups of adolescent children: non-athletes and athletes. In "indoor" athletes, the EIB prevalence was 22.4%. Among non-athletes, EIB was diagnosed in 10.2% (p = 0.007). A history of asthma was found in 6.5% of non-athletes and 29.3% of indoor athletes (p < 0.001). The incidence of EIB without asthma was higher in indoor athletes (14.6%) than in non-athletes (9.9%). Athletes achieved higher mean values in forced expiratory volume in one second (FEV₁), forced vital capacity (FVC), peak expiratory flow (PEF), and maximum expiratory flow rate at 25% (MEF₂₅) parameters. In the group of non-athletes, higher results were observed in forced expiratory volume in one second % of vital capacity (FEV₁%VC), MEF₅₀, and MEF₇₅. The findings of the study present the complexity of the EIB diagnosis among children training in an indoor environment.

Fractional exhaled nitric oxide in the assessment of exercise-induced bronchoconstriction: A multicenter retrospective analysis of UK-based athletes

INTRODUCTION

Exercise-induced bronchoconstriction (EIB) is not only highly prevalent in people with asthma, but can also occur independently, particularly in athletes. Fractional exhaled nitric oxide (FeNO) is an indirect biomarker of type 2 airway inflammation that has an established role in the assessment and management of asthma. The aim was to evaluate the value of FeNO in the assessment of EIB in athletes.

METHOD

Multicenter retrospective analysis. In total, 488 athletes (male: 76%) performed baseline FeNO, and spirometry pre- and post-indirect bronchial provocation via eucapnic voluntary hyperpnea (EVH). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for established FeNO thresholds-that is, intermediate (≥25 ppb) and high FeNO (≥40 ppb and ≥ 50 ppb)-and were evaluated against objective evidence of EIB (≥10% fall in FEV₁ ). The diagnostic accuracy of FeNO was calculated using receiver operating characteristics area under the curve (ROC-AUC).

RESULTS

Thirty-nine percent of the athletes had a post-EVH fall in FEV₁ consistent with EIB. FeNO values ≥25 ppb, ≥40 ppb, and ≥ 50 ppb were observed in 42%, 23%, and 17% of the cohort, respectively. The sensitivity of FeNO ≥25 ppb was 55%, which decreased to 37% and 27% at ≥40 ppb and ≥ 50 ppb, respectively. The specificity of FeNO ≥25 ppb, ≥40 ppb, and ≥ 50 ppb was 66%, 86%, and 89%, respectively. The ROC-AUC for FeNO was 0.656.

CONCLUSIONS

FeNO ≥40 ppb provides good specificity, that is, the ability to rule-in a diagnosis of EIB. However, due to the poor sensitivity and predictive values, FeNO should not be employed as a replacement for indirect bronchial provocation in athletes.

Effects of physical activity on lung function and quality of life in asthmatic children: An updated systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

The benefits of physical activity (PA) for asthmatic children were increasingly recognized, and as the design of studies on PA and asthma has become more refined in recent years, the latest evidence needed to be updated. We performed this meta-analysis to synthesize the evidence available from the last 10 years to update the effects of PA in asthmatic children.

METHODS

A systematic search was conducted in three databases, PubMed, Web of Science, and Cochrane Library. Randomized controlled trials were included, and two reviewers independently conducted the inclusion screening, data extraction, and bias assessment.

RESULTS

A total of 9 studies were included in this review after 3,919 articles screened. PA significantly improved the forced vital capacity (FVC) (MD 7.62; 95% CI: 3.46 to 11.78; p < 0.001), and forced expiratory flow between 25% and 75% of forced vital capacity (FEF_25-75) (MD 10.39; 95% CI: 2.96 to 17.82; p = 0.006) in lung function. There was no significant difference in forced expiratory volume in the first second (FEV₁) (MD 3.17; 95% CI: -2.82 to 9.15; p = 0.30) and fractional exhaled nitric oxide (FeNO) (MD -1.74; 95% CI: -11.36 to 7.88; p = 0.72). Also, PA significantly improved the quality of life as assessed by the Pediatric Asthma Quality of Life Questionnaire (all items p < 0.05).

CONCLUSIONS

This review suggested that PA could improve FVC, FEF_25-75, and quality of life in asthmatic children, but there was insufficient evidence of improvement in FEV₁ and airway inflammation.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022338984.

The impact of mental toughness and postural abnormalities on dysfunctional breathing in athletes

Background: While asthma and exercise-induced bronchoconstriction (EIB) can explain some cases of exertional dyspnea, the differential diagnosis of dyspnea is extensive. Dysfunctional breathing (DB) is a condition that is often overlooked and underdiagnosed. Pharmacologic treatments are available and widely utilized by clinicians for exertional dyspnea, but a better understanding of the non-pharmacologic treatments as well as psychological factors that play a role in DB can provide professional, elite amateurs, and recreational athletes with more therapeutic options.Measurement tools for mental toughness: Given the psychological components involved with these conditions, a tool to measure domains of sports mental toughness in athletes could help medical providers create a more comprehensive athlete profile which can be used in conjunction with standard pharmacologic therapy to provide a more effective treatment plan.Diagnosing DB: While normal breathing mechanics help shape appropriate posture and spinal stabilization, DB has been shown to contribute to pain and motor control deficits resulting in dysfunctional movement patterns, which further contribute to DB. Most respiratory specialists are unaware of how to assess the role of faulty sports technique, especially running gait, in dysfunctional breathing patterns making it difficult to recommend appropriate treatment and offer referrals for relevant therapies.Assessing postural changes: Three key components of proper running gait are reviewed and described in detail including trunk counter-rotation, extension of atlanto-occipital joint in conjunction with a forward tilted trunk, and ankle and hip joint range of motion.Conclusions: When underlying gait abnormalities and mental skills are addressed properly, they can disrupt poor breathing mechanics, facilitating a transition away from DB and toward healthier breathing patterns.KEY POINTS In summary, the following points should be considered when evaluating athletes who are having difficulty breathing even when compliant with their medications or if there is not an indication of asthma or EIB:Assess dysfunctional breathing (DB) with Nijmegen questionnaire (NQ).If DB is present, measure mental skills using the Sisu Quiz to determine an athlete's mental skills profile.Evaluate postural changes that may impact an athlete's ability to breathe.Using the three tools of the NQ, Sisu Quiz, and Postural assessments creates an athlete profile that is clinically useful to improve breathing technique.DB is often mistaken for other conditions for which medications are prescribed. By identifying DB early and making appropriate changes may negate or reduce the need for pharmacotherapy.Improving DB will improve athletic performance.

The interest of rehabilitation of respiratory disorders in athletes: Myth or reality?

BACKGROUND

Healthy trained athletes generally have an "overbuilt" respiratory system in order to face the huge ventilation and gas-exchange demand imposed by strenuous exercise. Athletes frequently complain of respiratory symptoms regardless of whether they have a diagnosed respiratory disease, therefore evoking a kind of respiratory limitation during exercise. Some respiratory pathologies athletes present are closely linked to exercise and include asthma, exercise-induced bronchoconstriction (EIB) or exercise-induced laryngeal obstruction. Management of asthma and EIB are mainly based on pharmacological treatments. However, many athletes still complain of respiratory symptoms despite optimal pharmacological treatments, which highlights the need for non-pharmacological approaches including breathing retraining, inspiratory muscle training and/or laryngeal exercise performed under the guidance of a physiotherapist in this specific population.

OBJECTIVES

With this literature overview, we aimed to report evidence supporting the interest of rehabilitation for athletes with respiratory disorders and discuss whether inspiratory muscle training programs can improve performance in healthy athletes.

METHODS

We searched MEDLINE and Cochrane databases for trials, reviews and meta-analyses assessing respiratory rehabilitation and muscle training programs in athletes by using the MesH terms "athletes", "asthma", "dyspnea", "rehabilitation" and "education" published from January 2010 to March 2020. The selection of articles was based on the author's expertise to elaborate this review of the literature.

RESULTS

Major findings suggest that breathing retraining may help asthmatic athletes better control their respiratory symptoms and that inspiratory muscle training may improve respiratory symptoms of exercise-induced laryngeal obstruction in athletes. Improvement of performance by respiratory muscle training still remains controversial.

CONCLUSIONS

Respiratory rehabilitation could be of interest in the specific population of athletes but should be further evaluated to improve the level of evidence of such strategies.