Metabolic insights at the finish line: deciphering physiological changes in ultramarathon runners through breath VOC analysis.

Exhaustive exercise can induce unique physiological responses in the lungs and other parts of the human body. The volatile organic compounds (VOCs) in exhaled breath are ideal for studying the effects of exhaustive exercise on the lungs due to the proximity of the breath matrix to the respiratory tract. As breath VOCs can originate from the bloodstream, changes in abundance should also indicate broader physiological effects of exhaustive exercise on the body.

Cystic Fibrosis Transmembrane Conductance Regulator Genotype, Not Circulating Catecholamines, Influences Cardiovascular Function in Patients with Cystic Fibrosis.

Background: Cystic fibrosis (CF) is a genetic disease affecting multiple organ systems of the body and is characterized by mutation in the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR). Previous work has shown that a single dose of aβ-agonist increases cardiac output (Q) and stroke volume (SV) and decreases systemic vascular resistance (SVR) in healthy subjects. This effect is attenuated in patients with CF; however, the mechanism is unknown.

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans.

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic responses to acute exercise are predominantly influenced by the duration and intensity of the exercise regimen. As exercise is increasingly thought of as a therapeutic treatment and/or diagnostic tool, it is important that standardizable methodologies be utilized to understand the variability and to increase the reproducibility of exercise outputs and measurements of responses to such regimens.

Exercise Stroke Volume in Adult Cystic Fibrosis: A Comparison of Acetylene Pulmonary Uptake and Oxygen Pulse.

Cardiac hemodynamic assessment during cardiopulmonary exercise testing (CPET) is proposed to play an important role in the clinical evaluation of individuals with cystic fibrosis (CF). Cardiac catheterization is not practical for routine clinical CPET. Use of oxygen pulse (Opulse) as a noninvasive estimate of stroke volume (SV) has not been validated in CF.

Effect of age on the presence of comet tails at high altitude.

Extravascular lung water (EVLW) increases in healthy adults upon exposure to high altitude, likely due to increased pulmonary vascular resistance (PVR). Older individuals experience increased PVR during exercise, which may be exacerbated by trekking at high altitude. This study aimed to determine whether EVLW development is greater in older versus younger adults during graded altitude exposure.

Influence of the Vibralung Acoustical Percussor on pulmonary function and sputum expectoration in individuals with cystic fibrosis.

Background: The Vibralung Acoustical Percussor is a new airway clearance therapy (ACT) utilizing intrapulmonary sound waves in addition to positive expiratory pressure (PEP). We evaluated the safety of the Vibralung and collected preliminary data on its ability to mediate sputum expectoration in individuals with cystic fibrosis (CF).

Methods: Over two separate studies, 10 and 11 mild to moderate CF patients were recruited for study I and II, respectively.

The influence of thoracic gas compression and airflow density dependence on the assessment of pulmonary function at high altitude.

The purpose of this report was to illustrate how thoracic gas compression (TGC) artifact, and differences in air density, may together conflate the interpretation of changes in the forced expiratory flows (FEFs) at high altitude (>2400 m). Twenty-four adults (10 women; 44 ± 15 year) with normal baseline pulmonary function (>90% predicted) completed a 12-day sojourn at Mt. Kilimanjaro.

Influence of dietary nitrate supplementation on lung function and exercise gas exchange in COPD patients.

Background: During exercise as pulmonary blood flow rises, pulmonary capillary blood volume increases and gas exchange surface area expands through distention and recruitment. We have previously demonstrated that pulmonary capillary recruitment is limited in COPD patients with poorer exercise tolerance. Hypoxia and endothelial dysfunction lead to pulmonary vascular dysregulation possibly in part related to nitric oxide related pathways.

The effect of diuresis on extravascular lung water and pulmonary function in acute decompensated heart failure.

Aims: The effect of extravascular lung water (EVLW) and relationship to functional status as a result of acute decompensated heart failure (ADHF) are not well understood. We sought to quantify changes in clinical variables, EVLW, airway anatomy, spirometry, and diffusing capacity for carbon monoxide before and after treatment for ADHF.

Methods And Results: Fifteen patients were recruited within 24 h of hospital admission.

Alveolar-capillary reserve during exercise in patients with chronic obstructive pulmonary disease.

Background: Factors limiting exercise in patients with COPD are complex. With evidence for accelerated pulmonary vascular aging, destruction of alveolar-capillary bed, and hypoxic pulmonary vasoconstriction, the ability to functionally expand surface area during exercise may become a primary limitation.

Purpose: To quantify measures of alveolar-capillary recruitment during exercise and the relationship to exercise capacity in a cohort of COPD patients.

Influence of Inhaled Amiloride on Lung Fluid Clearance in Response to Normobaric Hypoxia in Healthy Individuals.

Unlabelled: Wheatley, Courtney M., Sarah E. Baker, Bryan J.

Influence of resting lung diffusion on exercise capacity in patients with COPD.

Background: Lung diffusing capacity for carbon monoxide (DLCO) gives an overall assessment of functional lung surface area for gas exchange and can be assessed using various methods. DLCO is an important factor in exercise intolerance in patients with chronic obstructive pulmonary disease (COPD). We investigated if the intra-breath (IBDLCO) method may give a more sensitive measure of available gas exchange surface area than the more typical single breath (SBDLCO) method and if COPD subjects with the largest resting DLCO relative to pulmonary blood flow (Qc) would have a more preserved exercise capacity.

A systems biology approach to investigating the influence of exercise and fitness on the composition of leukocytes in peripheral blood.

Background: Exercise immunology has become a growing field in the past 20 years, with an emphasis on understanding how different forms of exercise affect immune function. Mechanistic studies are beginning to shed light on how exercise may impair the development of cancer or be used to augment cancer treatment. The beneficial effects of exercise on the immune system may be exploited to improve patient responses to cancer immunotherapy.

The Coupling of Peripheral Blood Pressure and Ventilatory Responses during Exercise in Young Adults with Cystic Fibrosis.

Purpose: Cystic fibrosis (CF) is commonly recognized as a pulmonary disease associated with reduced airway function. Another primary symptom of CF is low exercise capacity where ventilation and gas-exchange are exacerbated. However, an independent link between pathophysiology of the pulmonary system and abnormal ventilatory and gas-exchange responses during cardiopulmonary exercise testing (CPET) has not been established in CF.

Effect of β-adrenergic receptor stimulation on lung fluid in stable heart failure patients.

Background: The purpose of this study was to determine: (1) whether stable heart failure patients with reduced ejection fraction (HFrEF) have elevated extravascular lung water (EVLW) when compared with healthy control subjects; and (2) the effect of acute β-adrenergic receptor (βAR) agonist inhalation on lung fluid balance.

Methods: Twenty-two stable HFrEF patients and 18 age- and gender-matched healthy subjects were studied. Lung diffusing capacity for carbon monoxide (DLCO), alveolar-capillary membrane conductance (Dm), pulmonary capillary blood volume (V) (via re-breathe) and lung tissue volume (V) (via computed tomography) were assessed before and within 30 minutes after administration of nebulized albuterol.

Noninvasive assessment of cardiac output by brachial occlusion-cuff technique: comparison with the open-circuit acetylene washin method.

Cardiac output (CO) assessment as a basic hemodynamic parameter has been of interest in exercise physiology, cardiology, and anesthesiology. Noninvasive techniques available are technically challenging, and thus difficult to use outside of a clinical or laboratory setting. We propose a novel method of noninvasive CO assessment using a single, upper-arm cuff.

The Effect of Aging on Relationships between Lean Body Mass and VO2max in Rowers.

Aging is associated with a fall in maximal aerobic capacity as well as with a decline in lean body mass. The purpose of the study was to investigate the influence of aging on the relationship between aerobic capacity and lean body mass in subjects that chronically train both their upper and lower bodies. Eleven older rowers (58±5 yrs) and 11 younger rowers (27±4 yrs) participated in the study.

Impact of chronic systolic heart failure on lung structure-function relationships in large airways.

Heart failure (HF) is often associated with pulmonary congestion, reduced lung function, abnormal gas exchange, and dyspnea. We tested whether pulmonary congestion is associated with expanded vascular beds or an actual increase in extravascular lung water (EVLW) and how airway caliber is affected in stable HF Subsequently we assessed the influence of an inhaled short acting beta agonist (SABA). Thirty-one HF (7F; age, 62 ± 11 years; ht.

The relationship between cardiac hemodynamics and exercise tolerance in cystic fibrosis.

Background: Individuals with cystic fibrosis (CF) have reduced pulmonary function and exercise tolerance. Additionally, these individuals may develop abnormal cardiac function. The implications of abnormal cardiac function on exercise tolerance are unclear in CF.

Impaired cardiac and peripheral hemodynamic responses to inhaled β₂-agonist in cystic fibrosis.

Background: Pulmonary system dysfunction is a hallmark of cystic fibrosis (CF) disease. In addition to impaired cystic fibrosis transmembrane conductance regulator protein, dysfunctional β2-adrenergic receptors (β2AR) contribute to low airway function in CF. Recent observations suggest CF may also be associated with impaired cardiac function that is demonstrated by attenuated cardiac output (Q), stroke volume (SV), and cardiac power (CP) at both rest and during exercise.

Moderate intensity exercise mediates comparable increases in exhaled chloride as albuterol in individuals with cystic fibrosis.

Rationale: Despite the demonstrated advantageous systemic changes in response to regular exercise for individuals with cystic fibrosis (CF), exercise is still viewed as an elective rather than a vital component of therapy, and it is likely that these benefits extend to and are partially mediated by exercise-induced changes in ion regulation.

Objective: We sought to determine if exercise could provide comparable improvements in ion regulation in the CF lung as albuterol, measured using exhaled breath condensate (EBC) collection and nasal potential difference (NPD).

Methods: Fourteen CF (13-42 yrs.

Effects of exercise intensity compared to albuterol in individuals with cystic fibrosis.

Background: Although exercise is a vital component of the therapy prescribed to individuals with cystic fibrosis (CF), it is not a priority due to a finite amount of treatment time and the view that exercise is not as beneficial as pharmacological treatments by many individuals with CF. We sought to compare the therapeutic benefits of exercise and their prescribed bronchodilator albuterol.

Methods: CF (n = 14) and healthy (n = 16) subjects completed three visits, a baseline screening with VO2 max test and two treatment visits.

Sex differences in cardiovascular function during submaximal exercise in humans.

Differences in cardiovascular function between sexes have been documented at rest and maximal exercise. The purpose of this study was to examine the sex differences in cardiovascular function during submaximal constant-load exercise, which is not well understood. Thirty-one male and 33 female subjects completed nine minutes moderate and nine minutes vigorous intensity submaximal exercise (40 and 75% of peak watts determined by maximal exercise test).

Exhaled breath condensate detects baseline reductions in chloride and increases in response to albuterol in cystic fibrosis patients.

Impaired ion regulation and dehydration is the primary pathophysiology in cystic fibrosis (CF) lung disease. A potential application of exhaled breath condensate (EBC) collection is to assess airway surface liquid ionic composition at baseline and in response to pharmacological therapy in CF. Our aims were to determine if EBC could detect differences in ion regulation between CF and healthy and measure the effect of the albuterol on EBC ions in these populations.