Fibre-type-specific and Mitochondrial Biomarkers of Muscle Damage after Mountain Races.

Consequences of running mountain races on muscle damage were investigated by analysing serum muscle enzymes and fibre-type-specific sarcomere proteins. We studied 10 trained amateur and 6 highly trained runners who ran a 35 km and 55 km mountain trail race (MTR), respectively. Levels of creatine kinase (CK), CK-MB isoform (CK-MB), sarcomeric mitochondrial CK (sMtCK), transaminases (AST and ALT), cardiac troponin I (cTnI) and fast (FM) and slow myosin (SM) isoforms, were assessed before, 1 h, 24 h and 48 h after the beginning of MTR. Significant SM increases were found at 24 h in the 55 km group. Levels of CK, CK-MB, AST and cTnI were significantly elevated in both groups following MTR, but in the 55 km group they tended to stabilize in at 48 h. Using pooled data, time-independent serum peaks of SM and CK-MB were significantly correlated. Moreover, concentration of sMtCK was significantly elevated at 1 and 24 h after the race in the 35 km group. Although training volume could confer protection on the mitochondria, the increase in serum CK-MB and SM in the 55 km group might be related to damage to the contractile apparatus type I fibres. Competing in long-distance MTRs might be related to deeper type I muscle fibre damage, even in highly trained individuals.

Cardiac adaptation to endurance exercise training: Differential impact of swimming and running.

Objectives: High-intensity training has been associated with bi-ventricular and bi-atrial remodelling and a potentially increased risk of arrhythmias. Most of the evidence is based on endurance disciplines mainly involving the lower part of the body, while few data is available on upper body disciplines. The purpose of this study was to compare chronic cardiac remodelling induced by running and swimming as well as the acute response of ventricular and atrial performance after an upper-body and a lower-body endurance race. Methods: Standard and speckle tracking echocardiographic assessment of left ventricle, right ventricle and both atria was performed at baseline and immediately after a 9.5 km open-water swimming race in 26 healthy men and before and after a 35 km-trail-running race in 21 male runners. Results: No significant differences were observed in baseline ventricular dimensions. However, both right ventricular and atrial systolic deformation were greater in runners. This group also showed slightly larger atrial volumes as compared to swimmers. After the race, right ventricular dilatation was observed in both groups, but only runners showed a decrease in right ventricular deformation and a decrease in atrial volumes and deformation. Significant increases in atrial deformation without reduction in atrial volumes were observed only in swimmers after the race. Conclusions: Right ventricular and atrial remodelling is different depending on the endurance training discipline. Long-distance running races induce a greater impairment in right ventricular performance and atrial function compared to endurance swimming competitions.

Marathon Running Increases Synthesis and Decreases Catabolism of Joint Cartilage Type II Collagen Accompanied by High-Energy Demands and an Inflamatory Reaction.

Objective: To determine the effect of marathon running on serum levels of inflammatory, high energy, and cartilage matrix biomarkers and to ascertain whether these biomarkers levels correlate. Design: Blood samples from 17 Caucasian male recreational athletes at the Barcelona Marathon 2017 were collected at the baseline, immediately and 48 h post-race. Serum C reactive protein (CRP), creatin kinase (CK), and lactate dehydrogenase (LDH) were determined using an AU-5800 chemistry analyser. Serum levels of hyaluronan (HA), cartilage oligomeric matrix protein (COMP), aggrecan chondroitin sulphate 846 (CS846), glycoprotein YKL-40, human procollagen II N-terminal propeptide (PIINP), human type IIA collagen N-propeptide (PIIANP), and collagen type II cleavage (C2C) were measured by sandwich enzyme-linked immune-sorbent assay (ELISA). Results: Medians CK and sLDH levels increased (three-fold, two-fold) post-race [429 (332) U/L, 323 (69) U/L] (p < 0.0001; p < 0.0001) and (six-fold, 1.2-fold) 48 h post-race [658 (1,073) U/L, 218 (45) U/L] (p < 0.0001; p < 0.0001). Medians CRP increased (ten-fold) after 48 h post-race [6.8 (4.1) mg/L] (p < 0.0001). Mean sHA levels increased (four-fold) post-race (89.54 ± 53.14 ng/ml) (p < 0.0001). Means PIINP (9.05 ± 2.15 ng/ml) levels increased post-race (10.82 ± 3.44 ng/ml) (p = 0.053) and 48 h post-race (11.00 ± 2.96 ng/ml) (p = 0.001). Mean sC2C levels (220.83 ± 39.50 ng/ml) decreased post-race (188.67 ± 38.52 ng/ml) (p = 0.002). In contrast, means COMP, sCS846, sPIIANP, and median sYKL-40 were relatively stable. We found a positive association between sCK levels with sLDH pre-race (r = 0.758, p < 0.0001), post-race (r = 0.623, p = 0.008) and 48-h post-race (r = 0.842, p < 0.0001); sHA with sCRP post-race vs. 48 h post-race (r = 0.563, p = 0.019) and sPIINP with sCK pre-race vs. 48-h post-race (r = 0.499, p = 0.044) and with sLDH 48-h pre-race vs. post-race (r = 0.610, p = 0.009) and a negative correlation of sPIIANP with sCRP 48-h post-race (r = -0.570, p = 0.017). Conclusion: Marathon running is an exercise with high-energy demands (sCK and sLDH increase) that provokes a high and durable general inflammatory reaction (sCRP increase) and an immediately post-marathon mechanism to protect inflammation and cartilage (sHA increase). Accompanied by an increase in type II collagen cartilage fibrils synthesis (sPIINP increase) and a decrease in its catabolism (sC2C decrease), without changes in non-collagenous cartilage metabolism (sCOMP, sC846, and sYKL-40). Metabolic changes on sPIINP and sHA synthesis may be related to energy consumption (sCK, sLDH) and the inflammatory reaction (sCRP) produced.

Macronutrient and mineral intake effects on racing time and cardiovascular health in non-elite marathon runners.

OBJECTIVE: The aim of this study was to analyze the intake of specific macronutrients and minerals that could influence cardiovascular health in recreational marathon runners. METHODS: We grouped 37 male runners into two groups according to their 50th percentile race time (3.39 h) and divided them into fast (group 1 [G1]: 3.18 ± 0.18 h) and slow runners (group 2 [G2]: 3.84 ± 0.42 h). Anthropometric parameters, macronutrients, and mineral records were collected before the race. Minerals (sodium ion, potassium ion, and magnesium ion), lipid profile (triacylglycerols, low-density lipoprotein, high-density lipoprotein, and cholesterol), muscle damage (creatine kinase), inflammation (C-reactive protein), and cardiovascular health (high-sensitivity troponin T, ST2, and N-terminal proB-type natriuretic peptide) were analyzed in blood 24 h before, immediately after, and 48 h postrace. RESULTS: Weight (G1: 74.70 ± 7.76 kg, G2: 79.58 ± 6.72 kg; P < 0.05) and body mass index (G1: 23.01 ± 1.81 kg/m2, G2: 25.30 ± 2.02 kg/m2; P < 0.01) differed significantly between the groups. Moreover, G1 consumed significantly more (P < 0.01) mono- and polyunsaturated fatty acids than G2, and presented significantly higher iron, potassium, and magnesium intake. Regarding blood lipid profile, G2 presented significantly higher triacylglycerol values and lower levels of high-density lipoprotein (P < 0.01). The high-sensitivity troponin T marker of cardiac myocyte stress or injury was significantly higher (P < 0.05) in G2, reaching values >250 ng/L, and 81% of the runners (30 of 37) presented higher postrace values. CONCLUSIONS: Marathon runners consuming adequate amounts of unsaturated fat, iron, potassium, and magnesium, performed better and presented better cardiovascular health.

Altered GDF15 and FGF21 Levels in Response to Strenuous Exercise: A Study in Marathon Runners.

BACKGROUND: Recreational marathon runners face strong physiological challenges. Assessment of potential biomarkers for the biological responses of runners will help to discriminate individual race responsiveness and their physiological consequences. This study sought to analyze the changes in the plasma levels of GDF15 and FGF21, novel endocrine factors related to metabolic stress, in runners following the strenuous exercise of a marathon race. METHODS: Blood samples were obtained from eighteen male runners (mean ±SD, age: 41.7 ±5.0 years, BMI: 23.6 ± 1.8) 48 h before, immediately after, and 48 h after a marathon race, and from age-matched sedentary individuals. The level of GDF15, FGF21, and 38 additional biochemical and hematological parameters were determined. RESULTS: The basal levels of GDF15 and FGF21 did not differ between runners before the race and sedentary individuals. Significant increases in the mean levels of GDF15 (4.2-fold) and FGF21 (20-fold) were found in runners immediately after the race. The magnitudes of these increases differed markedly among individuals and did not correlate with each other. The GDF15 and FGF21 levels had returned to the basal level 48 h post-race. The post-race value of GDF15 (but not FGF21) correlated positively with increased total white cell count (r = 0.50, P = 0.01) and neutrophilia (r = 0.10, P = 0.01). CONCLUSION: GDF15 and FGF21 are transiently increased in runners following a marathon race. The induction of GDF15 levels is associated with alterations in circulating immune cells levels.

Relationship Between Bioimpedance Vector Displacement and Renal Function After a Marathon in Non-elite Runners.

Purpose: This study investigates the relationship between whole-body bioimpedance vector displacement, using bioelectrical impedance vector analysis (BIVA), and renal function through serum biomarkers [creatinine, urea, sodium, C-reactive protein (CRP), and creatine kinase] and urine biomarkers after a marathon. Methods: Bioimpedance measurements were taken among 19 non-elite runners at 24 h pre-race, immediately post-race, and at 48 h post-race. The bioimpedance measurements were analyzed by BIVA using the Hotelling's T2 test. The runners were divided according to a cutoff of serum creatinine level immediately post-race in G1 (<1.2 mg/dl of serum creatinine level) and G2 (≥1.2 mg/dl of serum creatinine level). The increase of the serum creatinine levels in 83% of G2 runners was related to acute kidney injury (AKI) stage 1. Results: Neither G1 nor G2 showed a creatinine clearance rate (CCr) lower than 60 ml/min. G2 showed a significant increase in CRP values at 48 h post-race vs baseline compared to G1 (P < 0.05), with over 5 mg/L (6.8-15.2) in 92% of the runners, and in CK values with over 215 U/L (282-1,882) at 48 h post-race in 100% of the runners. By BIVA, the 95% confidence ellipses of G2 showed shorter bioimpedance vectors than G1, with a noticeable minor Xc/H (P < 0.01), indicating an expansion on extracellular water and inflammation. The runners with 48 h post-race Xc/H values ≤30.5 Ω, with a decrease from -3 to -12% with respect to the Xc/H value at 24 h pre-race, indicated AKI stage 1 with 85.7% sensitivity and 91.7% specificity, with a direct correlation between AKI stage 1 with greater CRP values at 48 h post-race and bioimpedance vector displacement, but not with CK values at 48 h post-race. Conclusion: Through this data collection, it was evidenced that a transient reduction in renal function is more related to inflammatory factors than muscle damage. The BIVA method along with serum biomarkers could be used to follow up the kidney function in runners.

Effects of a polysaccharide-based multi-ingredient supplement on salivary immunity in non-elite marathon runners.

BACKGROUND: Extreme exercise may alter the innate immune system. Glycans are involved in several biological processes including immune system regulation. However, limited data regarding the impact of glycan supplementation on immunological parameters after strenuous exercise are available. We aimed to determine the impact of a standardized polysaccharide-based multi-ingredient supplement, Advanced Ambrotose© complex powder (AA) on salivary secretory Immunoglobulin A (sIgA) and pro- and anti-inflammatory protein levels before and after a marathon in non-elite runners. METHODS: Forty-one male marathon runners who completed the 42.195 km of the 2016 Barcelona marathon were randomly assigned to two study groups. Of them, n = 20 (48%) received the AA supplement for 15 days prior the race (AA group) and n = 21 (52%) did not receive any AA supplement (non-AA group). Saliva and blood samples were collected the day before the marathon and two days after the end of the race. Salivary IgA, pro-inflammatory chemokines (Gro-alpha, Gro-beta, MCP-1) and anti-inflammatory proteins (Angiogenin, ACRP, Siglec 5) were determined using commercially ELISA kits in saliva supernatant. Biochemical parameters, including C-reactive protein, cardiac biomarkers, and blood hemogram were also evaluated. RESULTS: Marathon runners who did not receive the AA supplement experienced a decrease of salivary sIgA and pro-inflammatory chemokines (Gro-alpha and Gro-beta) after the race, while runners with AA supplementation showed lower levels of anti-inflammatory chemokines (Angiogenin). Gro-alpha and Gro-beta salivary levels were lower before the race in the AA group and correlated with blood leukocytes and platelets. CONCLUSIONS: Changes in salivary sIgA and inflammatory chemokines, especially Gro-alfa and Gro-beta, were observed in marathon runners supplemented with AA prior to the race. These findings suggested that AA may have a positive effect on immune response after a strenuous exercise.

Salivary immunity and lower respiratory tract infections in non-elite marathon runners.

RATIONALE: Respiratory infections are common after strenuous exercise, when salivary immunity may be altered. We aim to investigate changes in salivary immunity after a marathon and its relationship with lower respiratory tract infections (LRTI) in healthy non-elite marathon runners. METHODS: Forty seven healthy marathon runners (28 males and 19 females) who completed the 42.195 km of the 2016 Barcelona marathon were studied. Saliva and blood samples were collected the day before the marathon and two days after the end of the race. Salivary IgA, antimicrobial proteins (lactoferrin, lysozyme) and chemokines (Groα, Groß, MCP-1) were determined using ELISA kits in saliva supernatant. Blood biochemistry and haemogram were analyzed in all participants. The presence of LRTI was considered in those runners who reported infectious lower respiratory tract symptoms during a minimum of 3 consecutive days in the 2 weeks after the race. RESULTS: Eight participants (17%) presented a LRTI during the 2 weeks of follow-up. Higher lysozyme levels were detected after the race in runners with LRTI when compared with those without infection. A decrease in salivary lysozyme, Groα and Groß levels after the race were observed in those runners who did not develop a LRTI when compared to basal levels. Salivary Groα levels correlated with basophil blood counts, and salivary lysozyme levels correlated with leukocyte blood counts. CONCLUSIONS: LRTI are common after a marathon race in non-elite healthy runners. Changes in salivary antimicrobial proteins and chemokines are related to the presence of LRTI and correlate with systemic defense cells, which suggest an important role of salivary immunity in the development of LRTI in non-elite marathon runners.

Affected pathways and transcriptional regulators in gene expression response to an ultra-marathon trail: Global and independent activity approaches.

Gene expression (GE) analyses on blood samples from marathon and half-marathon runners have reported significant impacts on the immune and inflammatory systems. An ultra-marathon trail (UMT) represents a greater effort due to its more testing conditions. For the first time, we report the genome-wide GE profiling in a group of 16 runners participating in an 82 km UMT competition. We quantified their differential GE profile before and after the race using HuGene2.0st microarrays (Affymetrix Inc., California, US). The results obtained were decomposed by means of an independent component analysis (ICA) targeting independent expression modes. We observed significant differences in the expression levels of 5,084 protein coding genes resulting in an overrepresentation of 14% of the human biological pathways from the Kyoto Encyclopedia of Genes and Genomes database. These were mainly clustered on terms related with protein synthesis repression, altered immune system and infectious diseases related mechanisms. In a second analysis, 27 out of the 196 transcriptional regulators (TRs) included in the Open Regulatory Annotation database were overrepresented. Among these TRs, we identified transcription factors from the hypoxia-inducible factors (HIF) family EPAS1 (p< 0.01) and HIF1A (p<0.001), and others jointly described in the gluconeogenesis program such as HNF4 (p< 0.001), EGR1 (p<0.001), CEBPA (p< 0.001) and a highly specific TR, YY1 (p<0.01). The five independent components, obtained from ICA, further revealed a down-regulation of 10 genes distributed in the complex I, III and V from the electron transport chain. This mitochondrial activity reduction is compatible with HIF-1 system activation. The vascular endothelial growth factor (VEGF) pathway, known to be regulated by HIF, also emerged (p<0.05). Additionally, and related to the brain rewarding circuit, the endocannabinoid signalling pathway was overrepresented (p<0.05).

The impact of moderate altitude on exercise metabolism in recreational sportsmen: a nuclear magnetic resonance metabolomic approach.

Although it is known that altitude impairs performance in endurance sports, there is no consensus on the involvement of energy substrates in this process. The objective of the present study was to determine whether the metabolomic pathways used during endurance exercise differ according to whether the effort is performed at sea level or at moderate altitude (at the same exercise intensity, using proton nuclear magnetic resonance, 1H NMR). Twenty subjects performed two 60-min endurance exercise tests at sea level and at 2150 m at identical relative intensity on a cycle ergometer. Blood plasma was obtained from venous blood samples drawn before and after exercise. 1H NMR spectral analysis was then performed on the plasma samples. A multivariate statistical technique was applied to the NMR data. The respective relative intensities of the sea level and altitude endurance tests were essentially the same when expressed as a percentage of the maximal oxygen uptake measured during the corresponding incremental maximal exercise test. Lipid use was similar at sea level and at altitude. In the plasma, levels of glucose, glutamine, alanine, and branched-chain amino acids had decreased after exercise at altitude but not after exercise at sea level. The decrease in plasma glucose and free amino acid levels observed after exercise at altitude indicated that increased involvement of the protein pathway was necessary but not sufficient for the maintenance of glycaemia. Metabolomics is a powerful means of gaining insight into the metabolic changes induced by exercise at altitude.

Pulmonary Vascular Function and Aerobic Exercise Capacity at Moderate Altitude.

PURPOSE: There has been suggestion that a greater "pulmonary vascular reserve" defined by a low pulmonary vascular resistance (PVR) and a high lung diffusing capacity (DL) allow for a superior aerobic exercise capacity. How pulmonary vascular reserve might affect exercise capacity at moderate altitude is not known. METHODS: Thirty-eight healthy subjects underwent an exercise stress echocardiography of the pulmonary circulation, combined with measurements of DL for nitric oxide (NO) and carbon monoxide (CO) and a cardiopulmonary exercise test at sea level and at an altitude of 2250 m. RESULTS: At rest, moderate altitude decreased arterial oxygen content (CaO2) from 19.1 ± 1.6 to 18.4 ± 1.7 mL·dL, P < 0.001, and slightly increased PVR, DLNO, and DLCO. Exercise at moderate altitude was associated with decreases in maximum O2 uptake (V˙O2max), from 51 ± 9 to 43 ± 8 mL·kg⋅min, P < 0.001, and CaO2 to 16.5 ± 1.7 mL·dL, P < 0.001, but no different cardiac output, PVR, and pulmonary vascular distensibility. DLNO was inversely correlated to the ventilatory equivalent of CO2 (V˙E/V˙CO2) at sea level and at moderate altitude. Independent determinants of V˙O2max as determined by a multivariable analysis were the slope of mean pulmonary artery pressure-cardiac output relationship, resting stroke volume, and resting DLNO at sea level as well as at moderate altitude. The magnitude of the decrease in V˙O2max at moderate altitude was independently predicted by more pronounced exercise-induced decrease in CaO2 at moderate altitude. CONCLUSION: Aerobic exercise capacity is similarly modulated by pulmonary vascular reserve at moderate altitude and at sea level. Decreased aerobic exercise capacity at moderate altitude is mainly explained by exercise-induced decrease in arterial oxygenation.

The Dynamics of Cardiovascular Biomarkers in non-Elite Marathon Runners.

The number of recreational/non-elite athletes participating in marathons is increasing, but data regarding impact of endurance exercise on cardiovascular health are conflicting. This study evaluated 79 recreational athletes of the 2016 Barcelona Marathon (72% men; mean age 39 ± 6 years; 71% ≥35 years). Blood samples were collected at baseline (24-48 h before the race), immediately after the race (1-2 h after the race), and 48-h post-race. Amino-terminal pro-B type natriuretic peptide (NT-proBNP, a marker of myocardial strain), ST2 (a marker of extracellular matrix remodeling and fibrosis, inflammation, and myocardial strain), and high-sensitivity troponin T (hs-TnT, a marker of myocyte stress/injury) were assayed. The median (interquartile range, IQR) years of training was 7 (5-11) years and median (IQR) weekly training hours was 6 (5-8) h/week, respectively. The median (IQR) race time (h:min:s) was 3:32:44 (3:18:50-3:51:46). Echocardiographic indices were within normal ranges. Immediately after the race, blood concentration of the three cardiac biomarkers increased significantly, with 1.3-, 1.6-, and 16-fold increases in NT-proBNP, ST2, and hs-TnT, respectively. We found an inverse relationship between weekly training hours and increased ST2 (p = 0.007), and a direct relationship between race time and increased hs-TnT (p < 0.001) and ST2 (p = 0.05). Our findings indicate that preparation for and participation in marathon running may affect multiple pathways affecting the cardiovascular system. More data and long-term follow-up studies in non-elite and elite athletes are needed.

Exercise-Induced Hypoxaemia Developed at Sea-Level Influences Responses to Exercise at Moderate Altitude.

PURPOSE: The aim of this study was to investigate the impact of exercise-induced hypoxaemia (EIH) developed at sea-level on exercise responses at moderate acute altitude. METHODS: Twenty three subjects divided in three groups of individuals: highly trained with EIH (n = 7); highly trained without EIH (n = 8) and untrained participants (n = 8) performed two maximal incremental tests at sea-level and at 2,150 m. Haemoglobin O2 saturation (SpO2), heart rate, oxygen uptake (VO2) and several ventilatory parameters were measured continuously during the tests. RESULTS: EIH athletes had a drop in SpO2 from 99 ± 0.8% to 91 ± 1.2% from rest to maximal exercise at sea-level, while the other groups did not exhibit a similar decrease. EIH athletes had a greater decrease in VO2max at altitude compared to non-EIH and untrained groups (-22 ± 7.9%, -16 ± 5.3% and -13 ± 9.4%, respectively). At altitude, non-EIH athletes had a similar drop in SpO2 as EIH athletes (13 ± 0.8%) but greater than untrained participants (6 ± 1.0%). EIH athletes showed greater decrease in maximal heart rate than non-EIH athletes at altitude (8 ± 3.3 bpm and 5 ± 2.9 bpm, respectively). CONCLUSION: EIH athletes demonstrated specific cardiorespiratory response to exercise at moderate altitude compared to non-EIH athletes with a higher decrease in VO2max certainly due to the lower ventilator and HRmax responses. Thus EIH phenomenon developed at sea-level negatively impact performance and cardiorespiratory responses at acute moderate altitude despite no potentiated O2 desaturation.

Inter-individual variability in right ventricle adaptation after an endurance race.

BACKGROUND: Right ventricle (RV) dysfunction has been described in athletes after endurance races. We aimed to understand and characterize the RV response to endurance exercise, the impact of individual variability and the effects of the amount of exercise. METHODS AND RESULTS: Echocardiography was performed in 55 healthy adults at baseline and after a three-stage trail race: short (14 km; n = 17); medium (35 km; n = 21); and long (56 km; n = 17). Standard and speckle tracking echocardiographic assessment of the RV was performed with global and separate analysis of the RV basal (inflow) and apical regions. Although no change was observed in the short distance runners, the RV systolic deformation decreased significantly (p < 0.05) after both the medium length and long races (Δ% RV global strain -7.6 ± 20.1 and -8.7 ± 21.8, respectively) with significant RV dilatation (Δ% RV volume +10.6 ± 9.9 and +15.3 ± 12.8, respectively). The RV basal segment made a major contribution to stroke volume during exercise, showing larger increases in size and strain compared with the apex. Various patterns of RV adaptation to exercise, ranging from increases in both RV segmental strains and sizes to an insufficient increase in size and a decrease in strain, were identified; this individual variability was not correlated with prior training. CONCLUSION: An acute RV impairment was demonstrated after a trail-running race and was related to the amount of exercise. A high inter-individual variability was observed. Differences in RV adaptation patterns were independent of prior training, suggesting the influence was due to other individual factors.

Acute, Exercise Dose-Dependent Impairment in Atrial Performance During an Endurance Race: 2D Ultrasound Speckle-Tracking Strain Analysis.

OBJECTIVES: This study sought to understand and characterize the acute atrial response to endurance exercise and the influence of the amount of exercise performed. BACKGROUND: Endurance exercise seems to be recognized as a risk factor for developing atrial arrhythmia. Atrial geometrical and functional remodeling may be the underlying substrate. METHODS: Echocardiography was performed in 55 healthy adults at baseline and after a 3-stage trail race: a short race (S) (14 km), n = 17; a medium race (M) (35 km), n = 21; and a long race (L) (56 km), n = 17. Analysis consisted of standard, speckle-tracking assessment of both the left ventricle (LV) and right ventricle (RV) and both the left atrium (LA) and the right atrium (RA): a-wave strain (Sa) and strain rate (Ra) as a surrogate for atrial contractile function and s-wave strain (St) and strain rate (SR) as reservoir function. RESULTS: After the race, RA reservoir function decreased in group M (Δ% SRs: -12.5) and further in group L (Δ% SRs: -15.4), with no changes in group S. RA contractile function decreased in group L (Δ% SRa: -9.3), showed no changes in group M (Δ% SRa: +0.7), and increased in group S (Δ% SRa: +14.8). A similar trend was documented in LA reservoir and contractile function but with less pronounced changes. The decrease in RA reservoir after the race correlated with the decrease in RV global longitudinal strain (GLS) (Δ% RVGLS vs. RASt and RASRs: +0.44; p < 0.05 and +0.41, respectively; p < 0.05). CONCLUSIONS: During a trail-running race, an acute exercise-dose dependent impairment in atrial function was observed, mostly in the RA, which was related to RV systolic dysfunction. The impact on atrial function of long-term endurance training might lead to atrial remodeling, favoring arrhythmia development.

Sarcomere Disruptions of Slow Fiber Resulting From Mountain Ultramarathon.

OBJECTIVE: To investigate changes after a mountain ultramarathon (MUM) in the serum concentration of fast (FM) and slow (SM) myosin isoforms, which are fiber-type-specific sarcomere proteins. The changes were compared against creatine kinase (CK), a widely used fiber-sarcolemma-damage biomarker, and cardiac troponin I (cTnI), a widely used cardiac biomarker. METHODS: Observational comparison of response in a single group of 8 endurance-trained amateur athletes. Time-related changes in serum levels of CK, cTnI, SM, and FM from competitors were analyzed before, 1 h after the MUM, and 24 and 48 h after the start of the MUM by 1-way ANOVA for repeated measures or Friedman and Wilcoxon tests. Pearson correlation coefficient was employed to examine associations between variables. RESULTS: While SM was significantly (P = .009) increased in serum 24 h after the beginning of the MUM, FM and cTnI did not change significantly. Serum CK activity peak was observed 1 h after the MUM (P = .002). Moreover, serum peaks of CK and SM were highly correlated (r = .884, P = .004). CONCLUSIONS: Since there is evidence of muscle damage after prolonged mountain running, the increase in SM serum concentration after a MUM could be indirect evidence of slow- (type I) fiber-specific sarcomere disruptions.

Ultra Pirineu 2017: características de los corredores de élite y de no élite y efectos sobre la salud de una maratón de montaña: estudio piloto Serialmed-UP / Ultra Pirineu 2017: Characteristics of elite and non-elite runners and effects on health of a mountain marathon: Serialmed-UP pilot study

Introducción: Incremento del número de participantes en carreras de larga distancia, así como el interés por conocer sus efectos sobre la salud. El objetivo principal es analizar las características de los corredores de una maratón de montaña, sus efectos sobre la salud y si existen diferencias entre los corredores de élite y de no élite. Métodos: El estudio Serialmed-UP es un estudio piloto, observacional, de cohortes prospectivo que se realizó en la Maratón Ultra Pirineu 2017. Se realizó una encuesta sobre hábitos de salud, alimentarios y de entrenamiento a los corredores de no élite. Se midieron las variables clínicas y analíticas antes y después de la carrera. Se realizó un estudio descriptivo y comparativo entre resultados antes y después de la carrera entre corredores de élite y de no élite. Resultados: Participaron 29 corredores, 22 de no élite y 7 de élite. Los de no élite son principalmente varones de mediana edad de 39 años, con buena salud cardiovascular (el 90,9% con revisiones médicas recientes), con alta carga de entrenamientos (asesoramiento profesional en el 72,7%) y buenos hábitos alimentarios (asesoramiento en el 54,5%). Antes de la carrera no había alteraciones clínicas ni analíticas, pero el 33,3% presentaban alteraciones en el ECG. Los hallazgos más destacables post-carrera fueron pérdida de peso (3% del peso corporal), insuficiencia renal aguda (66,7%) y alteraciones en el sodio (44%), fueron más significativos en los corredores de no élite. Conclusiones: Las carreras de larga distancia tienen repercusión en la salud de los corredores, sobre todo en los de no élite. Es necesario realizar más investigaciones para poder aportar recomendaciones personalizadas basadas en la evidencia científica

Introduction: There is an increase in the number of participants in long distance races as well as the interest in knowing their effects on health. Our main objective is to analyse the characteristics of mountain marathon runner, its effects on health and whether there are differences between elite and non-elite runners. Methods: The Serialmed-UP is a pilot, observational (cohort) prospective study carried out at the Ultra Pirineu Marathon 2017. A survey of health, nutrition and training habits was carried out among non-élite runners. Clinical and analytical variables were measured before and after the race. A descriptive and comparative study was performed between results before and after the race and among élite and non-élite runners. Results: 29 runners participated in the study, 22 non-élite and 7 élite. The non-élite were mostly men with a median age of 39 years-old, with good cardiovascular health (90.9% with recent medical check-ups), with a high load of training (professional counselling in 72.7%) and good eating habits (counselling in 54.5%). Before the race, there were no clinical or analytical alterations but 33.3% had alterations in the ECG. The most notable findings after the race were weight loss (3% of body weight), acute renal failure (66.7%) and alterations in sodium (44%), being these alterations more significant in non-élite runners. Conclusions: Long distance races have an impact on runners' health, especially among non-élite runners. We need more research in order to offer personalised recommendations based on scientific evidence

Suplementación con glicerina para prevenir la deshidratación en tareas simuladas de bomberos / Glycerol suplementation to prevent dehydration in simulated firemen tasks

Se han estudiado los efectos sobre diversos parámetros hematológicos y de la función renal, de una suplementación con glicerina y una solución hidratante, administrada previamente a la realización de tareas de simulacro de extinción de un fuego forestal en un grupo de once bomberos varones con un buen nivel de forma física. Los sujetos realizaron un primer periodo de hidratación forzada de180 minutos seguido de un periodo de ejercicio. Durante los primeros 30 minutos de hidratación ingirieron 500 ml de solución hidratante, seguido de cinco tomas de 200ml cada 30 minutos. Este mismo protocolo lo repitieron dos veces, uno con la solución hidratante que consistió en 1400 ml de agua con 100 g de glicerina para el grupo experimental (GLI) y otro con sólo 1500 ml de agua para el grupo control (CON). Durante la hora posterior a los dos periodos de hidratación, realizaron tres vueltas a un circuito físico-técnico de simulación de extinción de fuego forestal (desplazamiento cargando una mochila, carrera con mangueras, desplegamiento y recogida de mangueras, entre otras tareas) en un ambiente caluroso (±32ºC y±33% de humedad relativa). Las variables controladas fueron peso, diuresis, hematocrito y rendimiento. Resultados: a) el grupo experimental (GLI) tuvo una menor pérdida depeso después del subsiguiente periodo de ejercicio (CON:2.2 ± 0.8 % kgr, GLI: 1.6 ± 0.6 % kgr; b) La hidratación inducida con glicerina disminuyó muy significativamente la diuresis de los sujetos (CON: 1.5 ± 0.3 L, GLI: 0.85 ±0.3 L, p<0.001); c) No hubo diferencias significativas en el hematocrito entre las dos situaciones experimentales (AU)

The effects of glycerol supplementation in an oral hydration solution previous to firemen tasks (forest fire) have been studied in 11 fit firemen over hematologic parameters and renal function. On two occasions, the subjects completed a 180 minutes period of forced hydration followed by an exercise bout. During the first 30 minutes of hydration, subjects ingested 500 ml of hydrating solution followed by five equal ingestions of 200 ml every 30 minutes. Hydrating solution was 1400 ml of water with 100 g of glycerol for the experimental group (GLY) and 1500 ml of water alone for the control group (CON). Before one hour of the end of hydrating period, subjects completed three laps in a circuit-exercise simulating forest fire extinguishing tasks (walking carry on a backpack, running with sleeves, open out and pick up sleeves and other tasks) in a hot environment (±32ºC and ±33% relative humidity). The controlled variables were weight, diuresis, hematocrit and performance. Results: a) the experimental group (GLY)lost less body weight during the subsequent exercise bout(CON: 2.2 ± 0.8 % kgr, GLY: 1.6 ± 0.6 % kgr; b) Glycerol induced hydration very significantly decreased the subjects diuresis (CON: 1.5 ± 0.3 L, GLY: 0.85 ± 0.3 L, p<0.001);c) Hematocrit was not significantly different between two experimental conditions (AU)