Mechanisms of exercise-induced bronchoconstriction in athletes: Current perspectives and future challenges

Exercise Recommendations and Practical Considerations for Asthma Management-An EAACI Position Paper

Exercise is an important treatment for people with asthma and should be considered alongside pharmacological therapy when developing personalised asthma management plans. Despite this, there remains limited guidance concerning the practicalities of asthma-specific exercise prescription. This European Academy of Allergy and Clinical Immunology task force was therefore established to achieve three fundamental aims: first, to provide an up-to-date perspective concerning the role of exercise for asthma management (i.e., describe the disease modifying potential of exercise and associated impact on asthma-related extrapulmonary comorbidities); second, to develop pragmatic recommendations to facilitate safe and effective exercise prescription; and third, to identify key unmet needs and provide focused direction for future research. The position paper is structured as a practically focused document, with recommendations formulated according to best available scientific evidence and expert opinion, with an emphasis on providing healthcare providers with pragmatic advice that can be implemented during routine asthma review.

Effects of chronic exposure to biomass pollutants on cardiorespiratory responses and the occurrence of exercise-induced bronchoconstriction in healthy men

Exposure to charcoal biomass (CB) pollutants affects the cardiorespiratory system. We assessed cardiopulmonary responses (CPR) to exercise in charcoal producers (CPs) compared to farmers and evaluated the prevalence of exercise-induced bronchoconstriction (EIB). Forty-five CPs and 36 farmers, healthy males aged 23-39, completed a 15-m Incremental Shuttle Walk and Run Test (15-m ISWRT). Air quality index (AQI) and CO intoxication were measured, CPR was assessed through heart rate (HR), blood pressures (SBP, DBP), and spirometry at rest, peak exercise, and during recovery at 5 and 15 min. Aerobic capacity (VO2 max) was estimated from the distance covered during the 15-m ISWRT, and EIB was defined as a >10% decrease in FEV1 from baseline values. AQI was worse in charcoal workplaces, and CPs had higher CO intoxication than farmers (p < 0.0001). Both groups reached maximal exercise %HRmax: 84 (82-89) versus 84 (80-89), p = 0.37 and showed similar predicted VO2 max 36.2 (31.1-43.1) versus 38.9 (32.2-43.7) mL/kg/min, p = 0.60. However, after ISWRT, CPs had lower FEV1 than farmers (2.9 ± 0.6 vs. 3.3 ± 0.6 L, p < 0.003) and slower recovery. EIB prevalence was higher in CPs (60.0% vs. 27.8%, p = 0.006). Chronic exposure to CB increases EIB in healthy CPs, suggesting heightened airway hyperreactivity.

Midterm Effects of SARS-CoV-2 on Respiratory Function in Judokas With and Without Exercise-Induced Bronchoconstriction: A Retrospective Study

OBJECTIVES

The clinical consequences of coronavirus infection in elite judokas with exercise-induced bronchoconstriction (EIB) are unclear. We aimed to determine potential respiratory function abnormalities and recovery in athletes with and without EIB after severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection.

DESIGN

Retrospective cohort study.

SETTING

Türkiye Olympic Preparation Centre.

PARTICIPANTS

This retrospective study analyzed data collected from 25 consecutive elite judokas diagnosed with and without EIB and SARS-CoV-2 infection, routinely followed at an Olympic Sports Center between September 2020 and 2021.

INDEPENDENT VARIABLES

Respiratory muscle strength and pulmonary function data were collected before and up to 90 days after SARS-CoV-2 infection.

MAIN OUTCOME MEASURES

Measurements included maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), forced expiratory volume in 1 second (FEV 1 ), forced vital capacity (FVC), FEV 1 /FVC ratio, and peak expiratory flow (PEF).

RESULTS

Infected athletes with EIB had more markedly reduced respiratory muscle strength and pulmonary function than those without EIB. Maximal inspiratory pressure was decreased by 14% and MEP by 8% from baseline in infected athletes with EIB during follow-up. Likewise, FEV 1 and FVC decreased by 4%. Maximal inspiratory pressure, MEP, FEV 1 , and FVC remained abnormal after 90 days of SARS-CoV-2 infection in EIB athletes but normalized rapidly in non-EIB athletes. Peak expiratory flow seemed unaffected during follow-up. Exercise-induced bronchoconstriction severity was moderately correlated with the maximum fall in MEP during follow-up.

CONCLUSIONS

Severe acute respiratory syndrome coronavirus-2 infection notably decreases respiratory muscle strength and pulmonary function in judokas, especially those with pre-existing EIB, thereby prolonging spontaneous recovery time.

The Impact of Climate, Aeroallergens, Pollution, and Altitude on Exercise-Induced Bronchoconstriction

Exercise-induced bronchoconstriction (EIB) with or without underlying asthma is a condition with complex pathophysiology, where many factors play a role in its development and clinical presentation. EIB can be impacted by various environmental factors including climate, environmental allergens, air pollution, and altitude. Although it might be hard to escape one's environment, patients should nevertheless be counseled on how the environment could impact their symptoms. Patient education regarding environmental factors could help overcome impediments to exercise and improve performance.

Pulmonary function in swimmers exposed to disinfection by-products: a narrative review

Swimming produces many psychophysiological effects, including blood, hormonal, enzymatic, pulmonary, cardiovascular and energetic adaptations. However, asthma and allergies are becoming increasingly prevalent medical issues among elite endurance-trained swimmers, where exercise-induced asthma or bronchospasm is frequently reported. Heavy endurance swimming training, especially under adverse conditions, stresses the airway mucosa, leading to inflammatory changes, as observed in induced sputum in competitive swimmers. In addition, chlorine-based disinfectants (CBDs) are commonly used in indoor pools due to their effectiveness and lower relative cost. Many of these substances have carcinogenic and genotoxic properties, and exposure to DBPs have been linked to adverse respiratory effects. The association between long-term exposure to a chlorinated swimming pool and elevated serum sIgE levels suggests a link between allergens, chlorine exposure and the development of various pulmonary dysfunctions. Thus, the combination of intense and repeated physical endurance training over extended periods, along with suboptimal environmental conditions, may contribute to the development of rhinitis, asthma and bronchial hyperresponsiveness in athletes. While occasional or low-level exposure to chlorine might not be harmful, regular swimmers, especially those at competitive levels, are at a higher risk of developing respiratory disorders. Because these potential risks of exposure to CBDs must be balanced against the benefits of swimming and the risk of microbial infections in pools, we recommend better pool management and regular health checks for swimmers. Fortunately, the reduction of bronchial symptoms in swimmers who reduce training volume and intensity suggests that the negative effects on pulmonary function may be reversible. For these reasons, it is crucial to develop effective respiratory protection strategies, including medical interventions and modifications to the pool environment. Practical steps such as reducing chlorine use, ensuring proper hygiene before swimming and using swim caps can minimise risks. Research should also explore safer alternatives to CBDs, such as ozonation, and improved ventilation to reduce air pollutants.

The impact of tangeretin combined with whey protein on exercise-induced bronchoconstriction in professional athletes: a placebo-controlled trial

BACKGROUND

Exercise-induced bronchoconstriction (EIB) is highly prevalent in athletes. The objective of this study was to assess the therapeutic efficacy of daily tangeretin combined with whey protein supplementation over a period of 4 weeks in professional athletes with EIB.

METHODS

Using a placebo-controlled, double-blind, paired, randomized trial design, a cohort of 30 professional athletes with EIB, consisting of 14 females and 16 males, was divided into two groups: the tangeretin combined with whey protein intervention group (TIG), and the placebo control group (PCG). Both the TIG and PCG underwent exercise challenge tests (ECT) and VO2max tests before (ECT1, V1) and after (ECT2, V2) the intervention. Blood (eosinophils, neutrophils, and basophils) and serum (interleukin-5, IL-5; interleukin-8, IL-8; Clara cell secretory protein-16, CC16; immunoglobulin E, IgE) levels were measured early in the morning of ECT1 and ECT2, respectively. Lung function was assessed immediately before and post-ECT immediately.

RESULTS

Tangeretin combined with whey protein use for 4 weeks attenuated the decrease in forced expiratory volume in 1 s (FEV1) post trials (∆FEV1(ECT1-ECT2): mean (SD) TIG -7.51(6.9)% vs. PCG -2.33(11.49)%, p = 0.013). Tangeretin also substantially attenuated IL-5 concentration (∆IL-5(T1-T5): Tangeretin -19.4% vs Placebo + 8.37%, p = 0.022); IL-8 concentration (∆IL-8(T1-T5): Tangeretin -17.28% vs Placebo + 6.1%, p = 0.012); CC16 concentration (∆CC16(T1-T5): Tangeretin -11.77% vs Placebo + 24.19%); and IgE concentration in the serum (∆IgE(T1-T5): Tangeretin -24.1% vs Placebo -3.9%), and significantly decreased neutrophil count (∆N(T1-T5): Tangeretin -11.34% vs Placebo + 0.3%) and eosinophil count in blood (∆N(T1-T5): Tangeretin -38.5% vs Placebo + 4.35%). Compared with V1, VO2max (p = 0.042) and TLim (p = 0.05) of V2 were significantly increased in the TIG, and there was no significant change in the PCG. Meanwhile, six athletes in the TIG and 0 athletes in the PCG became EIB-negative at ECT2; the overall negative conversion rate of EIB was 40.00% in TCG. Additionally, the number of cough symptoms decreased from 9 to 3 and dyspnea from 4 to 2 in the TIG.

CONCLUSION

After high-intensity exercise, athletes with EIB achieved significant improvements in lung function and blood inflammatory factors by combining tangeretin and whey protein supplementation. EIB athletes also showed longer exercise endurance and VO2max at 4 weeks after TI. In addition, some patient symptoms disappeared after combination supplementation. The effect of this treatment on professional athletes with EIB was beneficial.

Exercise-Induced Bronchoconstriction in Children: State of the Art from Diagnosis to Treatment

Exercise-induced bronchoconstriction (EIB) is a common clinical entity in people with asthma. EIB is characterized by postexercise airway obstruction that results in symptoms such as coughing, dyspnea, wheezing, chest tightness, and increased fatigue. The underlying mechanism of EIB is not completely understood. "Osmotic theory" and "thermal or vascular theory" have been proposed. Initial assessment must include a specific work-up to exclude alternative diagnoses like exercise-induced laryngeal obstruction (EILO), cardiac disease, or physical deconditioning. Detailed medical history and clinical examination must be followed by basal spirometry and exercise challenge test. The standardized treadmill running (TR) test, a controlled and standardized method to assess bronchial response to exercise, is the most adopted exercise challenge test for children aged at least 8 years. In the TR test, the goal is to reach the target heart rate in a short period and maintain it for at least 6 min. The test is then followed by spirometry at specific time points (5, 10, 15, and 30 min after exercise). In addition, bronchoprovocation tests like dry air hyperpnea (exercise and eucapnic voluntary hyperpnea) or osmotic aerosols (inhaled mannitol) can be considered when the diagnosis is uncertain. Treatment options include both pharmacological and behavioral approaches. Considering medications, the use of short-acting beta-agonists (SABA) just before exercise is the commonest option strategy, but daily inhaled corticosteroids (ICS) can also be considered, especially when EIB is not controlled with SABA only or when the patients practice physical activity very often. Among the behavioral approaches, warm-up before exercise, breathing through the nose or face mask, and avoiding polluted environments are all recommended strategies to reduce EIB risk. This review summarizes the latest evidence published over the last 10 years on the pathogenesis, diagnosis using spirometry and indirect bronchoprovocation tests, and treatment strategies, including SABA and ICS, of EIB. A specific focus has been placed on EIB management in young athletes, since this condition can not only prevent them from practicing regular physical activity but also competitive sports.

Exhaled and Systemic Biomarkers to Aid the Diagnosis of Bronchial Asthma in Elite Water Sports Athletes

PURPOSE

Our aim was to evaluate the accuracy of a combined airway inflammatory biomarker assessment in diagnosing asthma in elite water sports athletes.

METHODS

Members of the Hungarian Olympic and Junior Swim Team and elite athletes from other aquatic disciplines were assessed for asthma by objective lung function measurements, and blood eosinophil count (BEC), serum total immunoglobulin E (IgE), fractional exhaled nitric oxide (F ENO ) measurements, and skin prick testing were performed. A scoring system from BEC, F ENO , serum IgE, and skin test positivity was constructed by dichotomizing the variables and assigning a score of 1 if the variable is elevated. These scores were summed to produce a final composite score ranging from 0 to 4.

RESULTS

A total of 48 participants were enrolled (age 21 ± 4 yr, 42% male), of which 22 were diagnosed with asthma. Serum total IgE and F ENO levels were higher in asthmatic individuals (68 [27-176] vs 24 [1-43], P = 0.01; 20 [17-26] vs 15 [11-22], P = 0.02), and positive prick test was also more frequent (55% vs 8%, P < 0.01). Asthmatic participants had higher composite variable scores (2 [1-3] vs 1 [0-1], P = 0.02). Receiver operating characteristic analysis showed that total IgE, F ENO , and composite variable were suitablefor identifying asthmatic participants (area under the curve = 0.72, P = 0.01; 0.70, P = 0.02, and 0.69, P = 0.03). A composite score of >2 reached a specificity of 96.2%, a sensitivity of 36.4%, and a likelihood ratio of 9.5. Logistic regression model revealed a strong association between the composite variable and the asthma diagnosis (OR = 2.71, 95% confidence interval = 1.17-6.23, P = 0.02).

CONCLUSIONS

Our data highlight the diagnostic value of combined assessment of Th2-type inflammation in elite water sports athletes. The proposed scoring system may be helpful in ruling in asthma in this population upon clinical suspicion.

Impact of Isolated Exercise-Induced Small Airway Dysfunction on Exercise Performance in Professional Male Cyclists

BACKGROUND

Professional cycling puts significant demands on the respiratory system. Exercise-induced bronchoconstriction (EIB) is a common problem in professional athletes. Small airways may be affected in isolation or in combination with a reduction in forced expiratory volume at the first second (FEV1). This study aimed to investigate isolated exercise-induced small airway dysfunction (SAD) in professional cyclists and assess the impact of this phenomenon on exercise capacity in this population.

MATERIALS AND METHODS

This research was conducted on professional cyclists with no history of asthma or atopy. Anthropometric characteristics were recorded, the training age was determined, and spirometry and specific markers, such as fractional exhaled nitric oxide (FeNO) and immunoglobulin E (IgE), were measured for all participants. All of the cyclists underwent cardiopulmonary exercise testing (CPET) followed by spirometry.

RESULTS

Compared with the controls, 1-FEV3/FVC (the fraction of the FVC that was not expired during the first 3 s of the FVC) was greater in athletes with EIB, but also in those with isolated exercise-induced SAD. The exercise capacity was lower in cyclists with isolated exercise-induced SAD than in the controls, but was similar to that in cyclists with EIB. This phenomenon appeared to be associated with a worse ventilatory reserve (VE/MVV%).

CONCLUSIONS

According to our data, it appears that professional cyclists may experience no beneficial impacts on their respiratory system. Strenuous endurance exercise can induce airway injury, which is followed by a restorative process. The repeated cycle of injury and repair can trigger the release of pro-inflammatory mediators, the disruption of the airway epithelial barrier, and plasma exudation, which gradually give rise to airway hyper-responsiveness, exercise-induced bronchoconstriction, intrabronchial inflammation, peribronchial fibrosis, and respiratory symptoms. The small airways may be affected in isolation or in combination with a reduction in FEV1. Cyclists with isolated exercise-induced SAD had lower exercise capacity than those in the control group.

Exercise-induced bronchoconstriction, allergy and sports in children

Exercise-induced bronchoconstriction (EIB) is characterized by the narrowing of airways during or after physical activity, leading to symptoms such as wheezing, coughing, and shortness of breath. Distinguishing between EIB and exercise-induced asthma (EIA) is essential, given their divergent therapeutic and prognostic considerations. EIB has been increasingly recognized as a significant concern in pediatric athletes. Moreover, studies indicate a noteworthy prevalence of EIB in children with atopic predispositions, unveiling a potential link between allergic sensitivities and exercise-induced respiratory symptoms, underpinned by an inflammatory reaction caused by mechanical, environmental, and genetic factors. Holistic management of EIB in children necessitates a correct diagnosis and a combination of pharmacological and non-pharmacological interventions. This review delves into the latest evidence concerning EIB in the pediatric population, exploring its associations with atopy and sports, and emphasizing the appropriate diagnostic and therapeutic approaches by highlighting various clinical scenarios.

Respiratory complications following COVID-19 in athletic populations: A narrative review

Athletes typically experience a mild-to-moderate, self-limiting illness following infection with the novel severe acute respiratory syndrome coronavirus 2. Some athletes, however, can develop prolonged symptoms, with breathlessness, cough, and chest tightness impacting return to training and competition. In athletes with persistent cardiopulmonary symptoms following COVID-19, focus is usually placed on the identification and characterization of cardiac complications, such as myocarditis. In this review, we focus on summarizing the literature assessing pulmonary complications and physiological consequences associated with COVID-19 illness in athletes. The review also provides recommendations for clinical assessment of the athlete with pulmonary issues following COVID-19 and directions for future research.

Asthma and exercise-induced bronchoconstriction in athletes: Diagnosis, treatment, and anti-doping challenges

Athletes often experience lower airway dysfunction, such as asthma and exercise-induced bronchoconstriction (EIB), which affects more than half the athletes in some sports, not least in endurance sports. Symptoms include coughing, wheezing, and breathlessness, alongside airway narrowing, hyperresponsiveness, and inflammation. Early diagnosis and management are essential. Not only because untreated or poorly managed asthma and EIB potentially affects competition performance and training, but also because untreated airway inflammation can result in airway epithelial damage, remodeling, and fibrosis. Asthma and EIB do not hinder performance, as advancements in treatment strategies have made it possible for affected athletes to compete at the highest level. However, practitioners and athletes must ensure that the treatment complies with general guidelines and anti-doping regulations to prevent the risk of a doping sanction because of inadvertently exceeding specified dosing limits. In this review, we describe considerations and challenges in diagnosing and managing athletes with asthma and EIB. We also discuss challenges facing athletes with asthma and EIB, while also being subject to anti-doping regulations.

Activation of epithelial and inflammatory pathways in adolescent elite athletes exposed to intense exercise and air pollution

RATIONALE

Participation in high-intensity exercise in early life might act as stressor to the airway barrier.

OBJECTIVES

To investigate the effect of intense exercise and associated exposure to air pollution on the airway barrier in adolescent elite athletes compared with healthy controls and to study exercise-induced bronchoconstriction (EIB) in this population.

METHODS

Early-career elite athletes attending 'Flemish-Elite-Sports-Schools' (12-18 years) of 4 different sport disciplines (n=90) and control subjects (n=25) were recruited. Presence of EIB was tested by the eucapnic voluntary hyperventilation (EVH) test. Markers at mRNA and protein level; RNA-sequencing; carbon load in airway macrophages were studied on induced sputum samples.

RESULTS

444 genes were differentially expressed in sputum from athletes compared with controls, which were related to inflammation and epithelial cell damage and sputum samples of athletes contained significantly more carbon loaded airway macrophages compared with controls (24%, 95% CI 20% to 36%, p<0.0004). Athletes had significantly higher substance P (13.3 pg/mL, 95% CI 2.0 to 19.2) and calprotectin (1237 ng/mL, 95% CI 531 to 2490) levels as well as IL-6, IL-8 and TNF-α mRNA levels compared with controls (p<0.05). The incidence of EIB in athletes was 9%. The maximal fall in forced expiratory volume in 1 s (%) after EVH test in athletes was significantly associated with prior PM10 and PM2.5 exposure.

CONCLUSION

Early-career elite athletes showed increased markers of air pollution exposure, epithelial damage and airway inflammation compared with controls. Acute exposure to increased air pollution PM10 levels was linked to increased airway hyper-reactivity.

TRIAL REGISTRATION NUMBER

NCT03587675.

Effect of Hydration on Pulmonary Function and Development of Exercise-Induced Bronchoconstriction among Professional Male Cyclists

BACKGROUND

Exercise-induced bronchoconstriction (EIB) is a common problem in elite athletes. Classical pathways in the development of EIB include the osmotic and thermal theory as well as the presence of epithelial injury in the airway, with local water loss being the main trigger of EIB. This study aimed to investigate the effects of systemic hydration on pulmonary function and to establish whether it can reverse dehydration-induced alterations in pulmonary function.

MATERIALS AND METHODS

This follow-up study was performed among professional cyclists, without a history of asthma and/or atopy. Anthropometric characteristics were recorded for all participants, and the training age was determined. In addition, pulmonary function tests and specific markers such as fractional exhaled nitric oxide (FeNO) and immunoglobulin E (IgE) were measured. All the athletes underwent body composition analysis and cardiopulmonary exercise testing (CPET). After CPET, spirometry was followed at the 3rd, 5th, 10th, 15th, and 30th min. This study was divided into two phases: before and after hydration. Cyclists, who experienced a decrease in Forced Expiratory Volume in one second (FEV₁) ≥ 10% and/or Maximal Mild-Expiratory Flow Rate (MEF_25-75) ≥ 20% after CPET in relation to the results of the spirometry before CPET, repeated the test in 15-20 days, following instructions for hydration.

RESULTS

One hundred male cyclists (n = 100) participated in Phase A. After exercise, there was a decrease in all spirometric parameters (p < 0.001). In Phase B, after hydration, in all comparisons, the changes in spirometric values were significantly lower than those in Phase A (p < 0.001).

CONCLUSIONS

The findings of this study suggest that professional cyclists have non-beneficial effects on respiratory function. Additionally, we found that systemic hydration has a positive effect on spirometry in cyclists. Of particular interest are small airways, which appear to be affected independently or in combination with the decrease in FEV₁. Our data suggest that pulmonary function improves systemic after hydration.

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.

A longitudinal study of exercise-induced bronchoconstriction and laryngeal obstruction in high school athletes

BACKGROUND

Exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO) are common in elite athletes. Knowledge of which factors are related to incident EIB and EILO is limited. The aim of this study was to explore the course of EIB and EILO in adolescent athletes over a 2 years period and baseline characteristics related to incident EIB.

METHODS

Questionnaire data on respiratory symptoms, asthma, and aeroallergy and results of objective EIB and EILO tests were collected from 58 participants (27 tested for EILO) at baseline and after 2 years (follow-up). Associations between incident EIB and baseline asthma-like symptoms, exercise-induced symptoms, fractional exhaled nitric oxide (FeNO), aeroallergy, and sex were assessed using logistic regression models.

RESULTS

Ten participants had incident EIB, and eight participants had persistent EIB. Five were EIB positive at baseline but negative at follow-up, while 35 participants were EIB negative at both time points. Having incident EIB was associated with reporting waking up with chest tightness (OR = 4.38; 95% CI: 1.06, 22.09). Reporting an increased number of asthma-like symptoms increased the likelihood of incident EIB (OR = 2.78; 95% CI: 1.16, 6.58). No associations were found between exercise-induced symptoms, FeNO, aeroallergy, or sex and incident EIB. Incident EILO was found in three and persistent EILO in two of the 27 participants tested.

CONCLUSION

Two in nine had incident EIB and one eighth had incident EILO, suggesting that recurrent testing for EIB and EILO may be relevant in young athletes. Particularly, EIB-negative athletes reporting multiple asthma-like symptoms could benefit from recurrent EIB testing.

How to detect young athletes at risk of exercise-induced bronchoconstriction?

Exercise-induced bronchoconstriction (EIB) is a prevalent condition in elite athletes caused by transient airway narrowing during or after exercise. Young athletes nowadays start early to perform high level exercise, highlighting the need to screen for EIB in a younger population. The purpose of this review is to evaluate current evidence of pre-tests with high probability to predict a positive provocation test in young and adolescent athletes, aged 12-24 years and thus indicate whether a young athlete is at risk of having EIB. Up to now, there is no validated screening test available to increase the pre-test probability of a provocation test of EIB in young and adolescent athletes. We would recommend that a clinical guideline committee might consider the development of a flow chart to screen for EIB in adolescent athletes. It could be composed of a symptom-based questionnaire focusing on wheezing during exercise, atopic state, reversibility test (to exclude EIB with asthma) and completed with markers in blood/serum. However, more research is necessary.

Asthma in elite athletes - do they have Type 2 or non-Type 2 disease? A new insight on the endotypes among elite athletes

Asthma and exercise-induced bronchoconstriction are highly prevalent in elite athletes compared with the general population. Some athletes have classic asthma with allergic sensitization; however, it seems that a proportion of athletes develop asthma as a result of several years of intensive training. It leads us to believe that asthma in athletes consists of at least two distinct endotypes - classic early-onset, Type 2 mediated asthma, and asthma with later onset caused by exercise which might be classified as non-Type 2 asthma. The purpose of this review is to evaluate the current literature on asthma in athletes focusing on inflammation and examine if asthma in athletes could be characterized as either Type 2- or non-Type 2 asthma.

Chlorine exposure and intensive exercise induces airway hyperreactivity in a 3-week murine exercise model

RATIONALE

Exercise-induced bronchoconstriction (EIB) is defined as acute narrowing of the airways during or immediately after exercise. EIB has a high prevalence in elite swimmers probably due to the high ventilation rate and exposure to the chlorine by-products. It is still puzzling which pathophysiological mechanisms drive EIB.

OBJECTIVE

In this study, we evaluated airway hyperreactivity, permeability, integrity and inflammation in a murine swimmers EIB model with and without chlorine exposure.

METHODS

Mice performed a 3-week swimming protocol in a swimming pool with counter current. Three hours after the last swimming session, airway hyperreactivity to methacholine was assessed. Cytokine levels and cellular differential analysis was performed in BAL fluid. Airway permeability and tight junction expression was measured in serum and lung tissue. T-, B-, dendritic and innate lymphoid cells were determined in lung tissue via flow cytometry.

RESULTS

A significant higher airway resistance (Rn; P < 0.0001) was observed in mice swimming in chlorinated water (mean Rn = 1.26 cmH₂O.s/ml) compared to mice swimming in tap water (mean Rn = 0.76 cmH₂O.s/ml) and both inhalation groups in the absence of cellular inflammation. No significant differences were found in lung immune cell populations or in lung tight junction mRNA expression. Experiments in SCID, Rag2^-/-γc^-/- or Cpa3^cre/+ mice showed a limited involvement of the innate, adaptive immune system or the mast cells.

CONCLUSION

Our 3-week swimming murine model mimics intensive swimming in chlorinated water with the presence of airway hyperreactivity in mice swimming in chlorinated water in the absence of airway inflammation and airway epithelial damage.

Diagnosis and management of allergy and respiratory disorders in sport: An EAACI task force position paper

Allergy and respiratory disorders are common in young athletic individuals. In the context of elite sport, it is essential to secure an accurate diagnosis in order to optimize health and performance. It is also important, however, to consider the potential impact or consequences of these disorders, in recreationally active individuals engaging in structured exercise and/or physical activity to maintain health and well-being across the lifespan. This EAACI Task Force was therefore established, to develop an up-to-date, research-informed position paper, detailing the optimal approach to the diagnosis and management of common exercise-related allergic and respiratory conditions. The recommendations are informed by a multidisciplinary panel of experts including allergists, pulmonologists, physiologists and sports physicians. The report is structured as a concise, practically focussed document, incorporating diagnostic and treatment algorithms, to provide a source of reference to aid clinical decision-making. Throughout, we signpost relevant learning resources to consolidate knowledge and understanding and conclude by highlighting future research priorities and unmet needs.

Physical exercise, immune response, and susceptibility to infections-current knowledge and growing research areas

This review presents state-of-the-art knowledge and identifies knowledge gaps for future research in the area of exercise-associated modifications of infection susceptibility. Regular moderate-intensity exercise is believed to have beneficial effects on immune health through lowering inflammation intensity and reducing susceptibility to respiratory infections. However, strenuous exercise, as performed by professional athletes, may promote infection: in about half of athletes presenting respiratory symptoms, no causative pathogen can be identified. Acute bouts of exercise enhance the release of pro-inflammatory mediators, which may induce infection-like respiratory symptoms. Relatively few studies have assessed the influence of regularly repeated exercise on the immune response and systemic inflammation compared to the effects of acute exercise. Additionally, ambient and environmental conditions may modify the systemic inflammatory response and infection susceptibility, particularly in outdoor athletes. Both acute and chronic regular exercise influence humoral and cellular immune response mechanisms, resulting in decreased specific and non-specific response in competitive athletes. The most promising areas of further research in exercise immunology include detailed immunological characterization of infection-prone and infection-resistant athletes, examining the efficacy of nutritional and pharmaceutical interventions as countermeasures to infection symptoms, and determining the influence of various exercise loads on susceptibility to infections with respiratory viruses, including SARS-CoV-2. By establishing a uniform definition of an "elite athlete," it will be possible to make a comparable and straightforward interpretation of data from different studies and settings.

Differences in lung function, bronchial hyperresponsiveness and respiratory health between elite athletes competing in different sports

Objectives: Examine lung function, bronchial hyperresponsiveness (BHR) and exercise-induced respiratory symptoms in elite athletes performing different sports.Methods: Norwegian national-team athletes (30 swimmers, 32 cross-country skiers, 16 speed-skaters, 11 rowers/paddlers, 17 handball players and 23 soccer players) completed a validated questionnaire, measured exhaled nitric oxide (FE_NO), spirometry, methacholine provocation (PD_20met) and skin prick test. Three cut-off levels defined BHR; i.e., PD_20met ≤2µmol, ≤4 µmol and ≤8µmol.Results: Mean forced vital capacity (FVC) was highest in swimmers (Mean z-score[95%CI] =1.16 [0.80, 1.51]), and close to or higher than reference values according to the Global Lung Initiative equation, across all sports. Mean forced expiratory volume in 1 second (FEV₁) was higher than reference values in swimmers (0.48 [0.13, 0.84]), and ball game athletes (0.69 [0.41, 0.97]). Mean forced expiratory flow between 25 and 75% of FVC (FEF_25-75), and/or FEV₁/FVC were lower than reference values in all endurance groups. BHR defined by ≤2 and ≤8 µmol methacholine was observed in respectively 50%-87% of swimmers, 25%-47% of cross-country skiers, 20%-53% of speed-skaters, 18%-36% and of rowers/paddlers, and 0%-17% of the ball game athletes. Exercise-induced symptoms were common in all groups, most frequent in cross-country skiers (88%), swimmers (83%) and speed-skaters (81%).Conclusion: Elite swimmers and ball game athletes had higher mean FVC and FEV₁, compared to reference values. However, FEF_25-75 and/or FEV₁/FVC was lower than the reference values in all endurance groups. The prevalence of BHR was high across all sports, except the ball game athletes, and most of the athletes reported exercise-induced respiratory symptoms.

Exposome mapping in chronic respiratory diseases: the added value of digital technology

PURPOSE OF REVIEW

The development and progression of chronic respiratory diseases are impacted by a complex interplay between genetic, microbial, and environmental factors. Here we specifically summarize the effects of environmental exposure on asthma, allergic rhinitis, and chronic rhinosinusitis. We furthermore discuss how digital health technology may aid in the assessment of the environmental exposure of patients and how it may be of added value for them.

RECENT FINDINGS

It is well established that one gets allergic symptoms if sensitized and exposed to the same allergen. Viruses, bacteria, pollutants, irritants, and lifestyle-related factors modify the risk of getting sensitized and develop symptoms or may induce symptoms themselves. Understanding these processes and how the various factors interact with each other and the human body require big data and advanced statistics. Mobile health technology enables integration of multiple sources of data of the patients' exposome and link these to patient outcomes. Such technologies may contribute to the increased understanding of the development of chronic respiratory disease.

SUMMARY

Implementation of digital technologies in clinical practice may in future guide the development of preventive strategies to tackle chronic respiratory diseases and eventually improve outcomes of the patient.

Does temperature matter for COVID-19 transmissibility? Evidence across Pakistani provinces

The outbreak of novel coronavirus (COVID-19) has become a global concern that is deteriorating environmental quality and damaging human health. Though some researchers have investigated the linkage between temperature and COVID-19 transmissibility across different geographical locations and over time, yet these studies are scarce. This study aims to bridge this gap using daily temperature and COVID-19 cases (transmissibility) by employing grey incidence analysis (GIA) models (i.e., Deng's grey incidence analysis (DGIA), the absolute degree GIA (ADGIA), the second synthetic degree GIA (SSDGIA), the conservative (maximin) model) and correlation analysis. Data on temperature are accessed from the NASA database, while the data on COVID-19 cases are collected from the official website of the government of Pakistan. Empirical results reveal the existence of linkages between temperature and COVID-19 in all Pakistani provinces. These linkages vary from a relatively stronger to a relatively weaker linkage. Based on calculated weights, the strength of linkages is ranked across provinces as follows: Gilgit Baltistan (0.715301) > Baluchistan (0.675091) > Khyber Pakhtunkhwa (0.619893) > Punjab (0.619286) > Sindh (0.601736). The disparity in the strength of linkage among provinces is explained by the discrepancy in the intensity of temperature. Besides, the diagrammatic correlation analysis shows that temperature is inversely linked to COVID-19 cases (per million persons) over time, implying that low temperatures are associated with high COVID-19 transmissibility and vice versa. This study is among the first of its kind to consider the linkages between temperature and COVID-19 transmissibility for a tropical climate country (Pakistan) using the advanced GIA models. Research findings provide an up-to-date glimpse of the outbreak and emphasize the need to raise public awareness about the devastating impacts of the COVID-19. The educational syllabus should provide information on the causes, signs, and precautions of the pandemic. Additionally, individuals should practice handwashing, social distancing, personal hygiene, mask-wearing, and the use of hand sanitizers to ensure a secure and supportive atmosphere for preventing and controlling the current pandemic.

Does temperature matter for COVID-19 transmissibility? Evidence across Pakistani provinces

The outbreak of novel coronavirus (COVID-19) has become a global concern that is deteriorating environmental quality and damaging human health. Though some researchers have investigated the linkage between temperature and COVID-19 transmissibility across different geographical locations and over time, yet these studies are scarce. This study aims to bridge this gap using daily temperature and COVID-19 cases (transmissibility) by employing grey incidence analysis (GIA) models (i.e., Deng's grey incidence analysis (DGIA), the absolute degree GIA (ADGIA), the second synthetic degree GIA (SSDGIA), the conservative (maximin) model) and correlation analysis. Data on temperature are accessed from the NASA database, while the data on COVID-19 cases are collected from the official website of the government of Pakistan. Empirical results reveal the existence of linkages between temperature and COVID-19 in all Pakistani provinces. These linkages vary from a relatively stronger to a relatively weaker linkage. Based on calculated weights, the strength of linkages is ranked across provinces as follows: Gilgit Baltistan (0.715301) > Baluchistan (0.675091) > Khyber Pakhtunkhwa (0.619893) > Punjab (0.619286) > Sindh (0.601736). The disparity in the strength of linkage among provinces is explained by the discrepancy in the intensity of temperature. Besides, the diagrammatic correlation analysis shows that temperature is inversely linked to COVID-19 cases (per million persons) over time, implying that low temperatures are associated with high COVID-19 transmissibility and vice versa. This study is among the first of its kind to consider the linkages between temperature and COVID-19 transmissibility for a tropical climate country (Pakistan) using the advanced GIA models. Research findings provide an up-to-date glimpse of the outbreak and emphasize the need to raise public awareness about the devastating impacts of the COVID-19. The educational syllabus should provide information on the causes, signs, and precautions of the pandemic. Additionally, individuals should practice handwashing, social distancing, personal hygiene, mask-wearing, and the use of hand sanitizers to ensure a secure and supportive atmosphere for preventing and controlling the current pandemic.

Tackling nasal symptoms in athletes: Moving towards personalized medicine

Adequate nasal breathing is indispensable for athletes, and nasal symptoms have been shown to interfere with their subjective feeling of comfortable breathing and quality of life. Nasal symptoms are caused by either structural abnormalities or mucosal pathology. Structural pathologies are managed differently from mucosal disease, and therefore, adequate diagnosis is of utmost importance in athletes in order to choose the correct treatment option for the individual. Literature suggests that nasal symptoms are more prevalent in athletes compared to the general population and certain sports environments might even trigger the development of symptoms. Given the high demands of respiratory function in athletes, insight into triggering factors is of high importance for disease prevention. Also, it has been suggested that athletes are more neglectful to their symptoms and hence remain undertreated, meaning that special attention should be paid to education of athletes and their caregivers. This review aims at giving an overview of nasal physiology in exercise as well as the possible types of nasal pathology. Additionally, diagnostic and treatment options are discussed and we focus on unmet needs for the management and prevention of these symptoms in athletes within the concept of precision medicine.

Asymmetric impact of temperature on COVID-19 spread in India: Evidence from quantile-on-quantile regression approach

The emergence of new coronavirus (SARS-CoV-2) has become a significant public health issue worldwide. Some researchers have identified a positive link between temperature and COVID-19 cases. However, no detailed research has highlighted the impact of temperature on COVID-19 spread in India. This study aims to fill this research gap by investigating the impact of temperature on COVID-19 spread in the five most affected Indian states. Quantile-on-Quantile regression (QQR) approach is employed to examine in what manner the quantiles of temperature influence the quantiles of COVID-19 cases. Empirical results confirm an asymmetric and heterogenous impact of temperature on COVID-19 spread across lower and higher quantiles of both variables. The results indicate a significant positive impact of temperature on COVID-19 spread in the three Indian states (Maharashtra, Andhra Pradesh, and Karnataka), predominantly in both low and high quantiles. Whereas, the other two states (Tamil Nadu and Uttar Pradesh) exhibit a mixed trend, as the lower quantiles in both states have a negative effect. However, this negative effect becomes weak at middle and higher quantiles. These research findings offer valuable policy recommendations.

Predictors of exercise-induced bronchoconstriction in subjects with mild asthma

Background

Physical effort is capable of triggering airway obstruction in asthmatics, the so-called exercise-induced bronchoconstriction in asthma (EIBa). This study was performed in subjects with mild persistent asthma, aiming to find predictors for developing EIBa.

Methods

In 20 subjects with mild asthma, measurements of baseline functional respiratory parameters and airways responsiveness by a methacholine challenge were obtained on the first day. A maximal, symptom-limited incremental cardiopulmonary exercise test (CPExT) was performed the day after, with subsequent, repeated maneuvers of maximal full forced expiration to monitor the FEV₁ change at 1,3,5,7,10 and 15 min after the end of the exercise.

Results

19 subjects completed the two-days protocol. No functional parameters both at rest and during effort were useful to predict EIBa after stopping exercise. In asthmatics with EIBa, mean Inspiratory Capacity (IC) did not increase with increasing ventilatory requirements during CPExT because 6 of them (50%) displayed dynamic pulmonary hyperinflation (DH), as documented by their progressive increase of end-expiratory lung volume. This subgroup, showing earlier post-exercise FEV₁ fall, had significantly lower forced mean expiratory flow between 25% and 75% of forced vital capacity (FEF_25-75%) at rest (p < 0.05) and higher airways responsiveness, expressed as PD₂₀FEV₁ (p < 0.05) as compared with other asthmatics with EIBa.

Conclusions

No functional respiratory parameters seem to predict EIBa in mild asthmatics. However, in those with EIBa, a subgroup developed DH during exercise, and this was associated with a baseline reduced forced expiratory flow rates at lower lung volumes and higher airway hyperresponsiveness, suggesting a prominent small airways impairment.

Management of Exercise-Induced Bronchoconstriction in Athletes

Exercise-induced bronchoconstriction (EIB) is a phenomenon observed in asthma but is also seen in healthy individuals and frequently in athletes. High prevalence rates are observed in athletes engaged in endurance sports, winter sports, and swimming. The pathophysiology of EIB is thought to be related to hyperventilation, cold air, and epithelial damage caused by chlorine and fine particles in inspired air. Several diagnostic procedures can be used; however, the diagnosis of EIB based on self-reported symptoms is not reliable and requires an objective examination. The hyperosmolar inhalation test and eucapnic voluntary hyperpnea test, which involve indirect stimulation of the airway, are useful for the diagnosis of EIB. A short-acting β-agonist is the first choice for prevention of EIB, and an inhaled corticosteroid is essential for patients with asthma. Furthermore, treatment should accommodate antidoping requirements in elite athletes. Tailoring of the therapeutic strategy to the individual case and the prognosis after cessation of athletic activity are issues that should be clarified in the future.

Exercise-Induced Bronchoconstriction in Iraq and Afghanistan Veterans With Deployment-Related Exposures

INTRODUCTION

Acute exposure to high-levels of ambient fine particulate matter while exercising results in airway narrowing, but the long-term effects of repeated exposure on exercise-induced bronchoconstriction (EIB) are not well known. The goal of this preliminary study is to determine the rate of EIB among a sample of non-treatment seeking veterans deployed to Iraq and Afghanistan.

MATERIALS AND METHODS

Twenty-four veterans (median [interquartile range]: 35.0 [27.3, 45] years) without history of asthma volunteered for this study. Spirometry was assessed before and after a standardized exercise challenge. A positive EIB response was defined as an exercise-induced fall in forced expiatory volume in 1 second ≥10%. Secondary criteria (peak flow ≥10% or mid-expiratory flow ≥15%) were also considered as an estimate of probable EIB.

RESULTS

A positive EIB response was observed in 16.7% and probable EIB response was observed in 41.7% of our sample. Median deployment length to Iraq or Afghanistan was 13.0 [10.3, 17.5] months and the median time since deployment was 4.2 [2.7, 7.7] years. At the time of testing, veterans reported persistent cough (58.3%), wheeze (37.5%), and shortness of breath (37.5%). During deployment, veterans reported exposure to dust and sand (70.8%), smoke from burn pits (66.7%), vehicle exhaust (83.3%), and regional air pollution (26.0%) on most days or daily.

CONCLUSIONS

Approximately 17% of our sample of non-treatment seeking deployed Iraq and Afghanistan veterans demonstrated EIB, similar to the general population prevalence. However, persistent respiratory symptoms and alternative indices of probable EIB supports continued monitoring of this population.

Differential effects of intense exercise and pollution on the airways in a murine model

Background

Exercise-induced bronchoconstriction (EIB) is a transient airway narrowing, occurring during or shortly after intensive exercise. It is highly prevalent in non-asthmatic outdoor endurance athletes suggesting an important contribution of air pollution in the development of EIB. Therefore, more research is necessary to investigate the combination of exercise and pollutants on the airways.

Methods

Balbc/ByJ mice were intranasally challenged 5 days a week for 3 weeks with saline or 0.2 mg/ml diesel exhaust particles (DEP), prior to a daily incremental running session or non-exercise session. Once a week, the early ventilatory response was measured and lung function was determined at day 24. Airway inflammation and cytokine levels were evaluated in bronchoalveolar lavage fluid. Furthermore, innate lymphoid cells, dendritic cells and tight junction mRNA expression were determined in lung tissue.

Results

Submaximal exercise resulted in acute alterations of the breathing pattern and significantly improved FEV_0.1 at day 24. DEP exposure induced neutrophilic airway inflammation, accompanied with increased percentages of CD11b⁺ DC in lung tissue and pro-inflammatory cytokines, such as IL-13, MCP-1, GM-CSF and KC. Occludin and claudin-1(Cldn-1) expression were respectively increased and decreased by DEP exposure. Whereas, exercise increased Cldn-3 and Cldn-18 expression. Combining exercise and DEP exposure resulted in significantly increased SP-D levels in the airways.

Conclusion

DEP exposure induced typical airway neutrophilia, DC recruitment and pro-inflammatory cytokine production. Whereas, intensive exercise induced changes of the breathing pattern. The combination of both triggers resulted in a dysregulation of tight junction expression, suggesting that intensive exercise in polluted environments can induce important changes in the airway physiology and integrity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-021-00401-6.

Effects of Exercise on the Skin Epithelial Barrier of Young Elite Athletes-Swimming Comparatively to Non-Water Sports Training Session

The benefits of swimming have been extensively assessed. However, swimming pools contain chlorine and other irritating chemicals that may induce contact dermatitis. To evaluate the effect of a swimming training session on transepidermal water loss (TWEL) in swimmers compared to football players, elite swimmers and football players were invited to participate (58 athletes) in the study, where TEWL was measured before, immediately after, and 30 min after a 2 h training session. The probe was held on the dorsum of the hand, volar forearm, and on the antecubital flexure for 1 min. The volar forearm, antecubital flexure, and hand dorsum showed a significant increase in TEWL in swimmers in both measurements after training compared to baseline (p < 0.001). In football players, an increase in TEWL was observed on the hands' dorsum between baseline and after training measurements. The variations on TEWL levels before and immediately after the training session were higher among swimmers on the volar forearm (p = 0.002) and antecubital flexure (p = 0.019). Our findings support the effect of the training environment-swimming pool versus outdoor sports-on the skin barrier function, with an increase of transepidermal water loss immediately after exercise. Exposure to a swimming pool environment in a 2 h training session may lead to changes in skin barrier function.

Exercise Related Respiratory Problems in the Young-Is It Exercise-Induced Bronchoconstriction or Laryngeal Obstruction?

Complaints of breathlessness during heavy exercise is common in children and adolescents, and represent expressions of a subjective feeling that may be difficult to verify and to link with specific diagnoses through objective tests. Exercise-induced asthma and exercise-induced laryngeal obstruction are two common medical causes of breathing difficulities in children and adolescents that can be challenging to distinguish between, based only on the complaints presented by patients. However, by applying a systematic clinical approach that includes rational use of tests, both conditions can usually be diagnosed reliably. In this invited mini-review, we suggest an approach we find feasible in our everyday clinical work.

Type 2 Inflammatory Biomarker Response After Exercise Challenge Testing

Introduction

Exercise-induced bronchoconstriction is due to osmotic stimulus of the airway epithelium and leads to a cascade of biomarker release from several inflammatory cells. Several type 2 (T2) mediators have been linked to exercise-induced bronchoconstriction, but the T2 response per se has not been described during exercise. The aim of this study was therefore to investigate T2 biomarkers in plasma and urine from subjects with asthma and healthy controls before and after an exercise challenge.

Methods

Twenty-two subjects with mild asthma and 18 healthy controls performed an exercise challenge test on a treadmill, and fractional exhaled NO (FeNO) was measured at baseline. Blood and urine samples were collected repeatedly during 60 min after the test and Interleukin-13 (IL-13), thymus and activation-related chemokine (TARC), periostin and leukotrienes were measured.

Results

Asthmatics and controls showed similar levels of IL-13, TARC, periostin and Cys-LT in plasma at baseline, and there were no differences in baseline levels between subjects with a negative and positive exercise challenge. After exercise, there was an overall increase in interleukin-13 (IL-13) in plasma in all subjects (p<0.001), with a peak at 10 min after the exercise challenge in both the asthmatic and control group. An increase in TARC in plasma was also seen (p<0.001), but only in the control subjects. In contrast, Cys-LT in plasma showed an overall decrease in all subjects (p<0.001), while periostin in plasma did not change. In conjunction with plasma, the level of IL-13 was increased in urine 30 min after the exercise challenge (p=0.002) and decreased again at 60 min (p=0.004). Similarly, leukotriene E₄ (LTE₄) was increased in urine samples, with a peak at 60 min and most pronounced in asthmatic subjects (p<0.001) but was seen also in controls (p=0.008).

Discussion

In conclusion, circulating levels of IL-13 are increased after exercise to the same extent in asthmatics and healthy control subjects, which indicates a physiological rather than a pathophysiological response. Also, the levels of TARC and leukotrienes were affected after exercise.

Repetitive Bouts of Exhaustive Exercise Induces a Systemic Inflammatory Response and Multi-Organ Damage in Rats

Multiple organ dysfunction syndrome can follow severe infection or injury, but its relationship to exercise is not well understood. Previous studies have observed that prolonged strenuous exercise can lead to transiently increased level and/or activity of markers for systemic inflammatory response and multiple organ damage. However, few studies have analyzed the pathogenesis of the inflammatory response and subsequent multi-organ injury in exhaustive exercise conditions. In this study, we established a rat model of repetitive bouts of exhaustive running (RBER) and investigated its effects on multiple organ damage. Rats were subjected to RBER in either uphill or downhill running modes daily for a period of 7 days. Morphologically, RBER causes tissue structural destruction and infiltration of inflammatory cells in the skeletal muscles and many visceral organs. RBER also causes sustained quantitative changes in leukocytes, erythrocytes, and platelets, and changes in the concentration of blood inflammatory factors. These inflammatory alterations are accompanied by increases in serum enzyme levels/activities which serve as functional markers of organ damage. In general, RBER in the downhill mode seemed to cause more damage evaluated by the above-mentioned measures than that produced in the uphill mode. A period of rest could recover some degree of damage, especially for organs such as the heart and kidneys with strong compensatory capacities. Together, our data suggest that, as a result of multi-organ interactions, RBER could cause a sustained inflammatory response for at least 24 h, resulting in tissue lesion and ultimately multiple organ dysfunction.

Prevalence and triggers of self-reported nasal hyperreactivity in adults with asthma

BACKGROUND

Nasal hyperreactivity (NHR) is a common feature of various rhinitis subtypes and represents a novel phenotype of rhinitis. It is being reported in two-thirds of adult rhinitis patients irrespective of the atopic status. Data on the prevalence of NHR in patients with asthma are lacking, as well as the nature of evoking triggers.

METHODS

Postal questionnaires were distributed to an unselected group of asthmatic patients in Leuven (Belgium, n = 190) and completed by 114 patients. In Mexico City (Mexico) and Brasov (Romania), respectively, 97 out of 110 and 80 out of 100 asthmatic patients attending the outpatient clinic completed the questionnaire. Non-asthmatic volunteers were recruited amongst university and hospital co-workers in Leuven (n = 53). The presence of self-reported NHR, the type of triggers evoking nasal and bronchial symptoms, medication use, self-reported allergy, and environmental factors were evaluated.

RESULTS

Overall, 69% of asthma patients reported NHR, with 32% having more than 4 triggers evoking NHR. These triggers included mainly exposure to temperature and humidity changes, cigarette smoke, and strong odours. A higher prevalence of NHR was detected in allergic compared to non-allergic asthma patients (73% vs. 53% p < 0.01). The prevalence of NHR correlated with asthma severity, ranging from 63% (VAS ≤3) to 81% (VAS ≥7). BHR was found more frequently in patients with NHR compared to without NHR (89% vs. 53%, p < 0.0001).

CONCLUSION

NHR represents a clinical phenotype of upper airway disease affecting over two-thirds of asthma patients and correlates with asthma severity. Targeting NHR in patients with asthma is often overlooked and should be reinforced in the future to achieve better symptom control.

The Relationship of IL-8 and IL-10 Myokines and Performance in Male Marathon Runners Presenting Exercise-Induced Bronchoconstriction

At present, it is unclear which exercise-induced factors, such as myokines, could diminish the negative impact of the reduction in pulmonary function imposed by the exercise in question. In this study, we aim to evaluate the prevalence of exercise-induced bronchoconstriction (EIB) and also to investigate the effect of myokines in the performance of marathon runners presenting EIB or not. Thirty-eight male recreational marathon runners (age 38.8 [33-44], height 175.7 [172.0-180.3]; weight 74.7 [69.3-81.6]) participated in this study, and through spirometry tests, a prevalence of 23.6% of EIB was found, which is in agreement with the literature. The volunteers who tested positive to EIB (EIB+) presented lower maximum aerobic capacity compared to those who tested negative (EIB-) (EIB+ 44.02 [39.56-47.02] and EIB- 47.62 [44.11-51.18] p = 0.03). The comparison of plasma levels of IL-1β (EIB+ p = 0.296, EIB- p = 0.176, EIB+ vs. EIB- baseline p = 0.190 immediately after p = 0.106), IL-4 (undetectable), IL-6 (EIB+ p = 0.003, EIB- p ≤ 0.001, EIB+ vs. EIB- baseline p = 0.301 immediately after p = 0.614), IL-8 (EIB+ p = 0.003, EIB- p ≤ 0.001, EIB+ vs. EIB- baseline p = 0.110 immediately after p = 0.453), IL-10 (EIB+ p = 0.003, EIB- p ≤ 0.001, EIB+ vs. EIB- baseline p = 0.424 immediately after p = 0.876) and TNF-α (EIB+ p = 0.003, EIB- p ≤ 0.001, EIB+ vs. EIB- baseline p = 0.141 immediately after p = 0.898) were similar in both groups 24 h before and immediately after the marathon. However, negative correlations were found between the marathon finishing time and the levels of IL-8 (r = -0.81, p = 0.022), and IL-10 (r = -0.97, p ≤ 0.001) immediately after completing the marathon. In conclusion, for the first time, it is shown that the myokines IL-8 and IL-10 are related to improvement of the performance of marathon runners presenting EIB.

Progress in understanding hypersensitivity reactions to nonsteroidal anti-inflammatory drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs), the medications most commonly used for treating pain and inflammation, are the main triggers of drug hypersensitivity reactions. The latest classification of NSAIDs hypersensitivity by the European Academy of Allergy and Clinical Immunology (EAACI) differentiates between cross-hypersensitivity reactions (CRs), associated with COX-1 inhibition, and selective reactions, associated with immunological mechanisms. Three phenotypes fill into the first group: NSAIDs-exacerbated respiratory disease, NSAIDs-exacerbated cutaneous disease and NSAIDs-induced urticaria/angioedema. Two phenotypes fill into the second one: single-NSAID-induced urticaria/angioedema/anaphylaxis and single-NSAID-induced delayed reactions. Diagnosis of NSAIDs hypersensitivity is hampered by different factors, including the lack of validated in vitro biomarkers and the uselessness of skin tests. The advances achieved over recent years recommend a re-evaluation of the EAACI classification, as it does not consider other phenotypes such as blended reactions (coexistence of cutaneous and respiratory symptoms) or food-dependent NSAID-induced anaphylaxis. In addition, it does not regard the natural evolution of phenotypes and their potential interconversion, the development of tolerance over time or the role of atopy. Here, we address these topics. A state of the art on the underlying mechanisms and on the approaches for biomarkers discovery is also provided, including genetic studies and available information on transcriptomics and metabolomics.

High incidence rate of asthma among elite endurance athletes: a prospective 4-year survey

Objective: The prevalence of asthma among elite endurance athletes is high, but less is known about the incidence of asthma among athletes. The aim of this study was to examine the incidence rate of physician-diagnosed asthma among elite endurance athletes.Method: An annual postal questionnaire was sent to an open prospective cohort of elite endurance athletes between 2011 and 2015. Athletes from Swedish National teams, students at universities with elite sport partnership, and pupils at Swedish National elite sport schools, competing in cross-country skiing, biathlon, ski orienteering, or orienteering were invited (n = 666). Incidence rate of physician-diagnosed asthma was calculated among those without asthma at baseline (n = 449). Risk factors for incident physician-diagnosed asthma were identified using a multivariate logistic regression analysis.Results: Response rate was 88.7% (n = 591) at baseline. The median age of participants was 17 (range 15-36) years at inclusion. The study population included 407 (69%) skiers and 184 (31%) orienteers. The prevalence of asthma at baseline was 23.9% (n = 141). Incidence rate (95% confidence interval [CI]) of physician-diagnosed asthma was 61.2 (45.7-80.3) per 1,000 person-years. Risk factors (odds ratio [OR (95% CI)]) for incident physician-diagnosed asthma were family history of asthma (1.97 [1.04-3.68]), being a skier (3.01 [1.42-7.21]), and wheezing without having a cold (4.15 [1.81-9.26]).Conclusion: The incidence rate of physician-diagnosed asthma is high among Swedish elite endurance athletes.

Exercise-induced bronchoconstriction in elite or endurance athletes:: Pathogenesis and diagnostic considerations

OBJECTIVE

To review the pathogenesis and evaluation of exercise-induced bronchoconstriction pertaining to the elite or endurance athlete, as well as propose a diagnostic algorithm based on the current literature.

DATA SOURCES

Studies were identified using Ovid MEDLINE and reference lists of key articles.

STUDY SELECTIONS

Randomized controlled trials were selected when available. Systematic reviews and meta-analyses of peer-reviewed literature were included, as were retrospective studies and observational studies of clinical interest.

RESULTS

Exercise-induced bronchoconstriction (EIB) is the physiologic entity in which exercise induces acute narrowing of the airways and occurs in patients both with and without asthma. It may present with or without respiratory symptoms, and the underlying cause is likely attributable to environment stressors to the airway encountered during exercise. These include the osmotic effects of inhaled dry air, temperature variations, autonomic nervous system dysregulation, sensory nerve reactivity, and airway epithelial injury. Deposition of allergens, particulate matter, and gaseous pollutants into the airway also contribute. Elite and endurance athletes are exposed to these stressors more frequently and in greater duration than the general population.

CONCLUSION

A greater awareness of EIB among elite and endurance athletes is needed, and a thorough evaluation should be performed if EIB is suspected in this population. We propose an algorithm to aid in this evaluation. Symptoms should not be solely relied on for diagnosis but should be taken into the context of bronchoprovocative challenges, which should replicate the competitive environment as closely as possible. Further research is needed to validate these tests' predictive values.

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

Diagnosing and treating elite and Olympic athletes with exercise-induced bronchoconstriction has been well established. However, a subset of elite and Olympic athletes with exercise-induced bronchoconstriction experience symptoms of breathlessness due to lack of adherence, improper medications, and/or generalized breathing dysfunction. A short review of traditional treatment plans for elite and Olympic athletes is presented along with the challenges of adherence, managing dysfunctional breathing, and measuring and treating mental skills deficits that may impact breathing. Elite and Olympic athletes may not respond to traditional treatment for exercise-induced bronchospasm, and we present some of the reasons why the athletes fail to respond. Furthermore, we present information on how to detect and treat elite and Olympic athletes with difficult-to-treat asthma. As part of this review we developed a flow diagram for medical providers to identify the reasons for lack of response to traditional treatment plans for exercise-induced bronchoconstriction with options for other treatment modalities.

Outdoor Endurance Training with Air Pollutant Exposure Versus Sedentary Lifestyle: A Comparison of Airway Immune Responses

Although regular exercise-training improves immune/inflammatory status, the influence of air pollutants exposure during outdoor endurance training compared to a sedentary lifestyle has not yet been clarified. This study aimed to compare the immune/inflammatory responses in the airways of street runners and sedentary people after acute and chronic particulate matter (PM) exposure. Forty volunteers (street runners (RUN, n = 20); sedentary people (SED, n = 20)) were evaluated 1 (acute) and 10 (chronic) weeks after PM exposure. Cytokines [interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, IL-13, and IL-17A] in nasal lavage fluid, salivary antibacterial peptides (lactoferrin (LTF), cathelicidin (LL-37), defensin-α 1-3), and secretory immunoglobulin A (SIgA), plasma club cell protein (CC16), and fractional exhaled nitric oxide (FeNO) were analyzed. After acute exposure, the RUN group showed lower levels of IL-13, IL-10, and FeNO, but higher defensin-α than the SED group. After chronic exposure, the RUN group showed elevation of IFN-γ, IL-10, IL-17A, and a decrease of FeNO levels, whereas the SED group showed elevation of TNF-α, IL-6, IL-10, and a decrease of IL-13 levels. Comparing these groups, the RUN group showed higher levels of SIgA and LTF, and lower FeNO levels than the SED group. In relation to the Th immune response analysis after acute and chronic PM exposure, the RUN group showed a pattern associated with Th1, while in the SED group, a Th2 pattern was found. Both groups showed also a Th17 immune response pattern. Our results allow us to suggest that the immune/inflammatory status of the respiratory tract after acute and chronic PM exposure was improved by the long-standing regular practice of outdoor endurance exercise compared to a sedentary lifestyle.

Exercise and Rhinitis in Athletes

Peak sporting performance requires optimal levels of health and fitness. Rhinitis, with its proven detrimental effects on sleep and mood, and its association with asthma, can clearly compromise athletic ability. Nasal health is therefore of key importance to the athlete. While not a limiting factor in a single exercise effort, the effects of nasal dysfunction can have repercussions in the post-exercise recovery period. Furthermore, it is linked with the development of asthma and may increase susceptibility to upper respiratory tract symptoms. This review aims to investigate the physiology of the nose during exercise, examine the relationship between exercise and nasal dysfunction, and consider the impact that dysfunction may have on an athlete. Lastly, the authors describe the diagnosis and treatment of rhinitis in athletes.

Asthma and exercise-induced respiratory disorders in athletes. The position paper of the Polish Society of Allergology and Polish Society of Sports Medicine

Exercise-induced respiratory symptoms describe acute airway narrowing that occurs as a result of exercise. It includes exercise-induced bronchoconstriction (EIB) and exercise-induced asthma (EIA) issues. To provide clinicians with practical guidelines, a multidisciplinary panel of stakeholders was convened to review the pathogenesis of EIB/EIA and to develop evidence-based guidelines for the diagnosis and treatment. Recommendations for the diagnosis and treatment of EIB were developed. High-intensity exercise in polluted environment (cold air, humidity, contamination, allergens) may increase the risk of EIB and asthma symptoms in athletes. Diagnostic procedures should include history taking, physical examination, atopy assessment and functional tests of the respiratory system. A strong recommendation was made for regular use of inhaled glucocorticosteroids and avoidance of short-acting β₂-agonists as the only treatment. The treatment of asthma in athletes should always take into account current anti-doping regulations. This position paper reflects the currently available evidence.

Omega-3 Polyunsaturated Fatty Acids: Benefits and Endpoints in Sport

The influence of nutrition has the potential to substantially affect physical function and body metabolism. Particular attention has been focused on omega-3 polyunsaturated fatty acids (n-3 PUFAs), which can be found both in terrestrial features and in the marine world. They are responsible for numerous cellular functions, such as signaling, cell membrane fluidity, and structural maintenance. They also regulate the nervous system, blood pressure, hematic clotting, glucose tolerance, and inflammatory processes, which may be useful in all inflammatory conditions. Animal models and cell-based models show that n-3 PUFAs can influence skeletal muscle metabolism. Furthermore, recent human studies demonstrate that they can influence not only the exercise and the metabolic response of skeletal muscle, but also the functional response for a period of exercise training. In addition, their potential anti-inflammatory and antioxidant activity may provide health benefits and performance improvement especially in those who practice physical activity, due to their increased reactive oxygen production. This review highlights the importance of n-3 PUFAs in our diet, which focuses on their potential healthy effects in sport.

The concepts of asthma endotypes and phenotypes to guide current and novel treatment strategies

INTRODUCTION

Asthma, a common, non-communicable chronic disease affects over 300 million individuals worldwide. The Western world lifestyle is claimed to be responsible for this high and increasing prevalence. Asthma has been defined as a syndrome with various phenotypes and endotypes, allergic asthma and type 2 asthma being the most frequent. A great increase in prevalence of allergic diseases has necessitated intensive investigations both for understanding the underlying mechanisms and for the development of novel therapy options with long-term efficacy and limited side-effects. Allergic patients demonstrate unique presentations with variable visible characteristics and disease outcomes depending on different molecular mechanisms, related to influence of genes and epigenetic control by micro- and macro-environment. Areas covered: This article reviews the definition of asthma phenotypes and possible endotypes, advances in allergy-immunology field and contemporary personalized therapy options for asthma. Expert commentary: Better understanding of the complex immune network of allergic inflammation and key players of immunity is continuously being provided for clarification of asthma sub-types. Successful therapy of asthma requires better definition of underlying pathogenesis, which sequentially could end up with 'custom-tailored' individualized, evidence-based and more precise therapy options; a new era termed as 'precision medicine'. Endotype, phenotype, theratype and biomarker terms arise as major keywords in precision/personalized medicine.