Small changes in lung function in runners with marathon-induced interstitial lung edema

Abstract

The purpose of this study was to assess lung function in runners with marathon‐induced lung edema. Thirty‐six (24 males) healthy subjects, 34 (SD 9) years old, body mass index 23.7 (2.6) kg/m2 had posterior/anterior (PA) radiographs taken 1 day before and 21 (6) minutes post marathon finish. Pulmonary function was performed 1–3 weeks before and 73 (27) minutes post finish. The PA radiographs were viewed together, as a set, and evaluated by two experienced readers separately who were blinded as to time the images were obtained. Radiographs were scored for edema based on four different radiological characteristics such that the summed scores for any runner could range from 0 (no edema) to a maximum of 8 (severe interstitial edema). Overall, the mean edema score increased significantly from 0.2 to 1.0 units (P <0.01), and from 0.0 to 2.9 units post exercise in the six subjects that were edema positive (P = 0.03). Despite a 2% decrease in forced vital capacity (FVC, P =0.024) and a 12% decrease in alveolar‐membrane diffusing capacity for carbon monoxide (DmCO, P =0.01), there was no relation between the change in the edema score and the change in DmCO or FVC. In conclusion, (1) mild pulmonary edema occurs in at least 17% of subjects and that changes in pulmonary function cannot predict the occurrence or severity of edema, (2) lung edema is of minimal physiological significance as marathon performance is unaffected, exercise‐induced arterial hypoxemia is unlikely, and postexercise pulmonary function changes are mild.

Thoraco-abdominal coordination and performance during uphill running at altitude

“…Similar increases in extravascular lung water have previously been described in outdoor environments in athletes immediately after both intense and prolonged exercise [18, 20] and in trekkers during high-altitude exposure with and without exercise [19, 53]. …”

“…In the present study, the lung echo assessment was performed immediately after the descent, but we do not think that this timing affected the results. In fact, it has been reported that the radiographic evidence of mild interstitial edema persists for at least one and a half hours post-marathon [20]. Also the development of asymptomatic interstitial lung edema can be involved in the decrease in lung volumes, as previously reported in athletes after an ultramarathon [20].…”

“…Studies have frequently shown a significant increase in pulmonary extravascular water following strenuous exercise, leading to mild interstitial pulmonary edema. Although small increases in interstitial water in the lungs do not cause overt clinical symptoms, they could contribute to lung-related limitations to exercise performance [20]. Interstitial pulmonary edema has been shown in endurance athletes after intense exercise at sea level using different imaging techniques such as chest X-ray, magnetic resonance imaging, computed tomography, and scintigraphy [21–23].…”

Extreme Mountain Ultra-Marathon Leads to Acute but Transient Increase in Cerebral Water Diffusivity and Plasma Biomarkers Levels Changes

“…As previous studies demonstrate, during and immediately after running, MUMs induce cardiac (Maufrais et al, 2016) and neuromuscular (Saugy et al, 2013) fatigue, lung functions alterations as pulmonary ventilations (Vernillo et al, 2015) as well as impairment in postural control (Degache et al, 2014). In parallel, an increase in total body water (Knechtle et al, 2008), in volumes of athletes' body extremities (e.g., feet) (Bracher et al, 2012) and the development of peripheral oedema have been identified (Zavorsky et al, 2014). Blood biomarkers changes also confirm this response, showing higher C-reactive protein concentrations (Millet et al, 2011a; Saugy et al, 2013) and decreased hematocrit levels in runners right after MUMs (Robach et al, 2014; Vitiello et al, 2015).…”

The blood transfer conductance for nitric oxide: Infinite vs. finite θ NO

“…Specifically, there is currently a debate as to whether to assume an infinite or finite θ NO when calculating alveolar-capillary membrane conductance (Dm CO ) and pulmonary-capillary blood volume (V C ) from measures of lung diffusing capacity for CO (DLCO) and NO (DLNO). While our laboratory has consistently held the original assumption that θ NO is effectively infinite, other groups have begun applying a finite value for θ NO of 4.5 ml CO /min/mmHg/ml blood measured via an in vitro study and supported by animal and human studies not designed to calculate an exact θ NO value (Borland and Cox, 1991; Borland et al, 2010; Guenard et al, 2016; Zavorsky et al, 2014). Based on this limited work, a task force has recently recommended the use of a finite θ NO ; however, we believe these recommendations, including those concerning θ NO and also the correct Dm NO /Dm CO ratio, are premature (Zavorsky et al, 2017).…”