Marathons and myasthenia gravis: a case report.
Birnbaum Simone,Sharshar Tarek,Eymard Bruno,Theaudin Marie,Portero Pierre,Hogrel Jean-Yves
BMC neurology
BACKGROUND:The cardinal symptoms of auto-immune myasthenia gravis are fatigue and weakness. Endurance events such as marathon running would seem incompatible with this chronic disease. Many patients stop sport altogether. There is limited literature of patients with auto-immune myasthenia gravis undergoing regular endurance exercise. CASE PRESENTATION:We report the case of a 36-year-old female who began long-distance running whilst experiencing initial symptoms of myasthenia gravis. She was diagnosed with auto-immune myasthenia gravis and whilst advised to stop all sport, her way of fighting and living with this chronic and unpredictable disease was to continue running to maintain a healthy body and mind. Despite suffering from ocular, bulbar and localized limb fatigability, she managed to complete multiple marathons and achieve disease stability with cholinesterase inhibitors. CONCLUSIONS:Marathon and half-marathon running lead to distinct changes in mediators of inflammation in an exercise-dose-dependent manner. Despite symptoms of weakness and fatigue in certain muscles in myasthenia gravis, physical exertion remains possible and may not worsen symptoms as demonstrated in this case and recent studies. The immunomodulatory role of exercise could be considered in this case however this hypothesis remains to be confirmed in future studies with quantitative data.
10.1186/s12883-018-1150-0
Marathon-Induced Cardiac Strain as Model for the Evaluation of Diagnostic microRNAs for Acute Myocardial Infarction.
Shirvani Samani Omid,Scherr Johannes,Kayvanpour Elham,Haas Jan,Lehmann David H,Gi Weng-Tein,Frese Karen S,Nietsch Rouven,Fehlmann Tobias,Sandke Steffi,Weis Tanja,Keller Andreas,Katus Hugo A,Halle Martin,Frey Norbert,Meder Benjamin,Sedaghat-Hamedani Farbod
Journal of clinical medicine
BACKGROUND:The current gold standard biomarker for myocardial infarction (MI), cardiac troponin (cTn), is recognized for its high sensitivity and organ specificity; however, it lacks diagnostic specificity. Numerous studies have introduced circulating microRNAs as potential biomarkers for MI. This study investigates the MI-specificity of these serum microRNAs by investigating myocardial stress/injury due to strenuous exercise. METHODS:MicroRNA biomarkers were retrieved by comprehensive review of 109 publications on diagnostic serum microRNAs for MI. MicroRNA levels were first measured by next-generation sequencing in pooled sera from runners ( = 46) before and after conducting a full competitive marathon. Hereafter, reverse transcription quantitative real-time PCR (qPCR) of 10 selected serum microRNAs in 210 marathon runners was performed (>10,000 qPCR measurements). RESULTS:27 potential diagnostic microRNA for MI were retrieved by the literature review. Eight microRNAs (miR-1-3p, miR-21-5p, miR-26a-5p, miR-122-5p, miR-133a-3p, miR-142-5p, miR-191-5p, miR-486-3p) showed positive correlations with cTnT in marathon runners, whereas two miRNAs (miR-134-5p and miR-499a-5p) showed no correlations. Upregulation of miR-133a-3p ( = 0.03) and miR-142-5p ( = 0.01) went along with elevated cTnT after marathon. CONCLUSION:Some MI-associated microRNAs (e.g., miR-133a-3p and miR-142-5p) have similar kinetics under strenuous exercise and MI as compared to cTnT, which suggests that their diagnostic specificity could be limited. In contrast, several MI-associated microRNAs (miR-26a-5p, miR-134-5p, miR-191-5p) showed different release behavior; hence, combining cTnT with these microRNAs within a multi-marker strategy may add diagnostic accuracy in MI.
10.3390/jcm11010005
Medical planning for mass-participation running events: a 3-year review of a half-marathon in Singapore.
Tan Clive M,Tan Ian Wern,Kok Wai Leong,Lee Melvin C,Lee Vernon J
BMC public health
BACKGROUND:Systematically planning appropriate medical coverage for mass-participation running events is a challenge that has received relatively little attention in the medical literature, despite its potentially severe consequences. In particular, the literature lacks quantitative information on running events that medical planners can utilize for decisions on medical resource allocation and deployment. METHODS:Using a case-study approach, this study provides a detailed quantitative medical services utilization profile for the Singapore Army Half-Marathon, constructed from participant and casualty data spanning three years and comprising over 80,000 data points. Casualty rates for participants of varying age and sex in different running events were also estimated using a multivariate logistic regression model. Qualitatively, planning processes and practices were described and discussed. RESULTS:The quantitative profile yielded three main findings. Firstly, the analysis reveals that the gross Medical Usage Rate had remained fairly stable at between 16.9 and 26.0 casualties per 10,000 participants over the three years. Secondly, comparing injury types, musculoskeletal and soft-tissue injuries were the most commonly-presented injuries. Thirdly, more casualties presented at the race end-point as compared to the along the race routes. The regression analysis showed that, of the four modeled variables, the longer event distance (21 km vs. 10 km) had the largest effect on the likelihood that a participant would become a casualty. Conversely, being of an older age, being male, and running in a non-competitive event were each associated with lower casualty risk. CONCLUSIONS:The stable and intuitive casualty patterns detailed in this study provide a strong basis for further quantitative research on the medical aspects of running events, as well as for mass-participation sporting events in general. The qualitative aspects of this report may serve as a useful resource to medical planners for running events.
10.1186/1471-2458-14-1109
Pacing strategies in marathons: A systematic review.
Heliyon
Background:The pacing strategy embodies the tactical behavior of athletes in distributing their energy across different segments of a race; therefore, a quantitative analysis of pacing strategies in marathon races could deepen the understanding of both pacing behavior and physical capacity in marathon athletics. Objective:The objective of this systematic review was to synthesize and characterize pacing strategies in marathon road races by exploring the categories of pacing strategies and the factors that influence these strategies during marathon events. Methods:Preferred Reporting Items for Systematic Reviews guidelines were followed for systematic searches, appraisals, and syntheses of literature on this topic. Electronic databases such as Science Direct, SPORTDiscuss, PubMed, and Web of Science were searched up to July 2024. Records were eligible if they included pace performance measurements during competition, without experimental intervention that may influence their pace, in healthy, adult athletes at any level. Results:A total of 39 studies were included in the review. Twenty-nine were observational studies, and 10 were experimental (randomized controlled trials). The assessment of article quality revealed an overall median NOS score of 8 (range 5-9). The included studies examined the pacing profiles of master athletes and finishers in half-marathon (n = 7, plus numbers compared to full marathon), full-marathon (n = 21), and ultramarathon (n = 11) road races. Considering that some studies refer to multiple pacing strategies, in general, 5 studies (∼13 %) reported even pacing, 3 (∼8 %) reported parabolic pacing, 7 (∼18 %) reported negative pacing, and 30 (∼77 %) reported positive pacing during marathon competitions. Gender, age, performance, pack, and physiological and psychological factors influence pacing strategies. Conclusion:This study synthesized pacing performance in marathons and highlighted the significance of examining pacing strategies in these events, offering valuable insights for coaches and athletes. Several key findings were highlighted: (1) pacing profiles and pacing ranges were identified as the primary indicators of pacing strategies; (2) the pacing strategy was found to be dynamic, with the most substantial effects attributed to gender and distance; and (3) three distinct types of pacing strategies for marathons were classified: positive, negative, and even pacing. These findings advance the understanding of marathon pacing strategies by shedding light on the factors that influence athletes' pacing decisions and behaviors. Additionally, these findings offer practical benefits, aiding athletes in making well-informed tactical choices and developing effective pace plans to enhance marathon performance. However, due to the complex nature of marathon racing, further research is required to explore additional factors that might impact pacing strategies. A better grasp of optimal pacing strategies will foster progress in this area and serve as a basis for future research and advancements.
10.1016/j.heliyon.2024.e36760
Thermoregulation and marathon running: biological and environmental influences.
Cheuvront S N,Haymes E M
Sports medicine (Auckland, N.Z.)
The extreme physical endurance demands and varied environmental settings of marathon footraces have provided a unique opportunity to study the limits of human thermoregulation for more than a century. High post-race rectal temperatures (Tre) are commonly and consistently documented in marathon runners, yet a clear divergence of thought surrounds the cause for this observation. A close examination of the literature reveals that this phenomenon is commonly attributed to either biological (dehydration, metabolic rate, gender) or environmental factors. Marathon climatic conditions vary as much as their course topography and can change considerably from year to year and even from start to finish in the same race. The fact that climate can significantly limit temperature regulation and performance is evident from the direct relationship between heat casualties and Wet Bulb Globe Temperature (WBGT), as well as the inverse relationship between record setting race performances and ambient temperatures. However, the usual range of compensable racing environments actually appears to play more of an indirect role in predicting Tre by acting to modulate heat loss and fluid balance. The importance of fluid balance in thermoregulation is well established. Dehydration-mediated perturbations in blood volume and blood flow can compromise exercise heat loss and increase thermal strain. Although progressive dehydration reduces heat dissipation and increases Tre during exercise, the loss of plasma volume contributing to this effect is not always observed for prolonged running and may therefore complicate the predictive influence of dehydration on Tre for marathon running. Metabolic heat production consequent to muscle contraction creates an internal heat load proportional to exercise intensity. The correlation between running speed and Tre, especially over the final stages of a marathon event, is often significant but fails to reliably explain more than a fraction of the variability in post-marathon Tre. Additionally, the submaximal exercise intensities observed throughout 42 km races suggest the need for other synergistic factors or circumstances in explaining this occurrence. There is a paucity of research on women marathon runners. Some biological determinants of exercise thermoregulation, including body mass, surface area-to-mass ratio, sweat rate, and menstrual cycle phase are gender-discrete variables with the potential to alter the exercise-thermoregulatory response to different environments, fluid intake, and exercise metabolism. However, these gender differences appear to be more quantitative than qualitative for most marathon road racing environments.
10.2165/00007256-200131100-00004
Advanced quantitative magnetic resonance imaging of lower extremity muscle microtrauma after marathon: a mini review.
Frontiers in sports and active living
This article reviews the existing literature and outlines recent advances in quantitative Magnetic Resonance Imaging (MRI) techniques for the assessment of lower extremity muscle microtrauma following a marathon. Single-modality quantitative MRI techniques include T2 mapping to assess the dynamics of muscle inflammatory edema and variability at the site of injury, Diffusion Tensor Imaging (DTI) to detect subclinical changes in muscle injury, Intravoxel Incoherent Motion (IVIM) imaging to provide simultaneous information on perfusion and diffusion in muscle tissue without the need for intravenous contrast, and Magnetic Resonance Spectroscopy (MRS) to noninvasively detect intramyocellular lipid (IMCL) content in muscle before and after marathon exercise to explain the use of fatty acids as an energy source in skeletal muscle during long-distance running. As well as Chemical Exchange Saturation Transfer (CEST) is particularly suitable for detecting changes in free creatine, pH values and lactate concentrations in muscles before and after exercise, providing a more detailed picture of muscle physiology and chemistry. These metabolic MRI methods enhance the understanding of biochemical alterations occurring in muscles pre- and post-exercise. Multimodal techniques combine different modalities to provide a comprehensive evaluation of muscle structural and functional changes. These advanced techniques aim to better assess microtrauma and guide clinical treatment, though further validation with larger studies is needed to establish their potential over traditional qualitative methods.
10.3389/fspor.2024.1481731
The "athlete's heart" features in amateur male marathon runners.
Lewicka-Potocka Zuzanna,Dąbrowska-Kugacka Alicja,Lewicka Ewa,Kaleta Anna Maria,Dorniak Karolina,Daniłowicz-Szymanowicz Ludmiła,Fijałkowski Marcin,Nabiałek-Trojanowska Izabela,Ratkowski Wojciech,Potocki Wojciech,Raczak Grzegorz
Cardiology journal
BACKGROUND:Training on a professional level can lead to cardiac structural adaptations called the "athlete's heart". As marathon participation requires intense physical preparation, the question arises whether the features of "athlete's heart" can also develop in recreational runners. METHODS:The study included 34 males (mean age 40 ± 8 years) who underwent physical examination, a cardiopulmonary exercise test and echocardiographic examination (ECHO) before a marathon. ECHO results were compared with the sedentary control group, reference values for an adult male population and those for highly-trained athletes. Runners with abnormalities revealed by ECHO were referred for cardiac magnetic resonance imaging (CMR). RESULTS:The mean training distance was 56.5 ± 19.7 km/week, peak oxygen uptake was 53.7 ± 6.9 mL/kg/min and the marathon finishing time was 3.7 ± 0.4 h. Compared to sedentary controls, amateur athletes presented larger atria, increased left ventricular (LV) wall thickness, larger LV mass and basal right ventricular (RV) inflow diameter (p < 0.05). When compared with ranges for the general adult population, 56% of participants showed increased left atrial volume, indexed to body surface area (LAVI), 56% right atrial area and interventricular septum thickness, while 47% had enlarged RV proximal outflow tract diameter. In 50% of cases, LAVI exceeded values reported for highly-trained athletes. Due to ECHO abnormalities, CMR was performed in 6 participants, which revealed hypertrophic cardiomyopathy in 1 runner. CONCLUSIONS:"Athlete's heart" features occur in amateur marathon runners. In this group, ECHO reference values for highly-trained elite athletes should be considered, rather than those for the general population and even then LAVI can exceed the upper normal value.
10.5603/CJ.a2019.0110
Cardiovascular magnetic resonance with parametric mapping in long-term ultra-marathon runners.
Małek Łukasz A,Barczuk-Falęcka Marzena,Werys Konrad,Czajkowska Anna,Mróz Anna,Witek Katarzyna,Burrage Matthew,Bakalarski Wawrzyniec,Nowicki Dariusz,Roik Danuta,Brzewski Michał
European journal of radiology
PURPOSE:There is a direct reverse dose-effect relationship between the amount of physical activity and cardiovascular risk. It is unknown whether this is true for extreme, persistent endurance training. The aim of the study was to assess structural changes of the heart in long-time ultra-marathon runners with special focus on myocardial fibrosis using parametric mapping. METHOD:We studied a group of 30 healthy, male ultra-marathon runners (mean age 40.9 ± 6.6 yrs, median 9 yrs of running with frequent competitions) and 10 matched controls not engaged in any regular activities. All of them underwent cardiovascular magnetic resonance (CMR) with 3 T scanner including T1-mapping, late gadolinium enhancement (LGE) and extracellular volume (ECV) quantification. RESULTS:Athletes demonstrated significantly larger heart chambers and left ventricular (LV) mass. LV systolic function was unchanged. 73.3% of athletes fulfilled volumetric criteria for dilated cardiomyopathy or arrhythmogenic right ventricular cardiomyopathy. Non-ischemic, small volume LGE was found in 8 athletes and in 1 control (27% vs. 10%, p = 0.40). It was localised at insertion points (5 athletes, 1 control) or in the septum or infero-lateral wall (3 athletes). Athletes with insertion point LGE had higher right ventricular end-diastolic volume index in comparison to athletes without LGE (p = 0.04), which suggests its relation to volume overload. There were no differences between athletes and non-athletes in terms of ECV values (26.1% vs. 25%, p = 0.29). CONCLUSIONS:Ultra-marathon runner's hearts demonstrate a high degree of structural remodelling, but there is no significant increase in focal or diffuse myocardial fibrosis.
10.1016/j.ejrad.2019.06.001
Deformation Parameters of the Heart in Endurance Athletes and in Patients with Dilated Cardiomyopathy-A Cardiac Magnetic Resonance Study.
Małek Łukasz A,Mazurkiewicz Łukasz,Marszałek Mikołaj,Barczuk-Falęcka Marzena,Simon Jenny E,Grzybowski Jacek,Miłosz-Wieczorek Barbara,Postuła Marek,Marczak Magdalena
Diagnostics (Basel, Switzerland)
A better understanding of the left ventricle (LV) and right ventricle (RV) functioning would help with the differentiation between athlete's heart and dilated cardiomyopathy (DCM). We aimed to analyse deformation parameters in endurance athletes relative to patients with DCM using cardiac magnetic resonance feature tracking (CMR-FT). The study included males of a similar age: 22 ultramarathon runners, 22 patients with DCM and 21 sedentary healthy controls (41 ± 9 years). The analysed parameters were peak LV global longitudinal, circumferential and radial strains (GLS, GCS and GRS, respectively); peak LV torsion; peak RV GLS. The peak LV GLS was similar in controls and athletes, but lower in DCM ( < 0.0001). Peak LV GCS and GRS decreased from controls to DCM (both < 0.0001). The best value for differentiation between DCM and other groups was found for the LV ejection fraction (area under the curve (AUC) = 0.990, = 0.0001, with 90.9% sensitivity and 100% specificity for ≤53%) and the peak LV GRS diastolic rate (AUC = 0.987, = 0.0001, with 100% sensitivity and 88.4% specificity for >-1.27 s). The peak LV GRS diastolic rate was the only independent predictor of DCM ( = 0.003). Distinctive deformation patterns that were typical for each of the analysed groups existed and can help to differentiate between athlete's heart, a nonathletic heart and a dilated cardiomyopathy.
10.3390/diagnostics11020374
Two dimensional and real-time three dimensional ultrasound measurements of left ventricular diastolic function after marathon running: results from a substudy of the BeMaGIC trial.
Roeh Astrid,Schuster Tibor,Jung Philip,Schneider Jens,Halle Martin,Scherr Johannes
The international journal of cardiovascular imaging
Strenuous exercise results in transient but minor alterations in left ventricular diastolic function (LVDF). The aim of this study is to describe and interpret the kinetics of the well-established 2D parameters of diastolic function and the novel and very sensitive 3D parameters before/after a marathon race. LVDF was evaluated by transthoracic echocardiography (TEE) in 212 healthy male [aged 42 (36-49) years)] marathon runners (all Be-MaGIC-study) in the week prior to (V1), immediately after (V2), 24 h after (V3) and 72 h after (V4) a marathon race. Real time three-dimensional echocardiography (RT3DE) included maximal and minimal left atrium (LA) volume, total LA ejection fraction (Total-EF), total LA stroke volume (Total-SV), true ejection fraction (True-EF) and atrial stroke volume (ASV). After adjustment for possible confounders (heart rate and systolic blood pressure), 2D Parameters of left ventricular inflow (E/A-ratio) decreased from pre- to immediately post-race (- 0.3 ± 0.06, p < 0.001) and returned to baseline within 24 h. [Formula: see text]-ratio remained unchanged directly post-race, but was significantly increased during follow-up of 24 and 72 h. 3D LA V was increased immediately postrace and in the 24 h follow-up, LA V was increased immediately post-race and in the follow-up of 24 and 72 h. During follow-up of 72 h, but not immediately postrace, TrueEF and ASV were significantly increased. Both techniques revealed acute and prolonged alterations of diastolic LV function. Considering all parameters, the recovery of diastolic LV after a marathon seems to take longer than previously assumed.Trial registration ClinicalTrials.gov ID: NCT00933218.
10.1007/s10554-019-01634-5
Cardiac structure and function in response to a multi-stage marathon over 4486 km.
Klenk Christopher,Brunner Horst,Nickel Thomas,Sagmeister Florian,Yilmaz Atilgan,Infanger Denis,Billich Christian,Scharhag Jürgen,Vogeser Michael,Beer Meinrad,Schütz Uwe,Schmidt-Trucksäss Arno
European journal of preventive cardiology
AIMS:To investigate whether participation in the Trans Europe Foot Race 2009 (TEFR), an ultramarathon race held over 64 consecutive days and 4486 km, led to changes in cardiac structure and function. METHODS:Cardiac magnetic resonance imaging was performed in 20 of 67 participating runners (two women; mean ± SD age 47.8 ± 10.4 years) at three time points (baseline scan at 294 ± 135 km (B), scan two at 1735 ± 86 km (T1) and scan three at 3370 ± 90 km (T2)) during the TEFR. Imaging included an assessment of left ventricular structure (mass) and function (strain). In parallel, cardiac troponin I, NT-pro-BNP, myostatin and GDF11 were determined in venous blood samples. A subsample of ten runners returned for a follow-up scan eight months after the race. RESULTS:Left ventricular mass increased significantly (B, 158.5 ± 23.8 g; T1, 165.1 ± 23.2 g; T2, 167 ± 24.6 g; < 0.001) over the course of the race, although no significant change was seen in the remaining structural and functional parameters. Serum concentrations of cardiac troponin I and NT-proBNP significantly increased 1.5 - and 3.5-fold, respectively, during the first measurement interval, with no further increase thereafter (cardiac troponin I, 6.8 ± 3.1 (B), 16.9 ± 10.4 (T1) and 17.1 ± 9.7 (T2); NT-proBNP, 30.3 ± 22.8 (B), 135.9 ± 177.5 (T1) and 111.2 ± 87.3 (T2)), whereas the growth markers myostatin and GDF11 did not change. No association was observed with functional parameters, including the ejection fraction and the volume of both ventricles. The follow-up scans showed a reduction to baseline values (left ventricular mass 157 ± 19.3 g). CONCLUSIONS:High exercise-induced cardiac volume load for >2 months in ultra-endurance runners results in a physiological structural adaptation with no sign of adverse cardiovascular remodelling.
10.1177/2047487319885035
Cardiac structure and function in response to a multi-stage marathon over 4486 km.
European journal of preventive cardiology
AIMS:To investigate whether participation in the Trans Europe Foot Race 2009 (TEFR), an ultramarathon race held over 64 consecutive days and 4486 km, led to changes in cardiac structure and function. METHODS:Cardiac magnetic resonance imaging was performed in 20 of 67 participating runners (two women; mean ± SD age 47.8 ± 10.4 years) at three time points (baseline scan at 294 ± 135 km (B), scan two at 1735 ± 86 km (T1) and scan three at 3370 ± 90 km (T2)) during the TEFR. Imaging included an assessment of left ventricular structure (mass) and function (strain). In parallel, cardiac troponin I, NT-pro-BNP, myostatin and GDF11 were determined in venous blood samples. A subsample of ten runners returned for a follow-up scan eight months after the race. RESULTS:Left ventricular mass increased significantly (B, 158.5 ± 23.8 g; T1, 165.1 ± 23.2 g; T2, 167 ± 24.6 g; p < 0.001) over the course of the race, although no significant change was seen in the remaining structural and functional parameters. Serum concentrations of cardiac troponin I and NT-proBNP significantly increased 1.5 - and 3.5-fold, respectively, during the first measurement interval, with no further increase thereafter (cardiac troponin I, 6.8 ± 3.1 (B), 16.9 ± 10.4 (T1) and 17.1 ± 9.7 (T2); NT-proBNP, 30.3 ± 22.8 (B), 135.9 ± 177.5 (T1) and 111.2 ± 87.3 (T2)), whereas the growth markers myostatin and GDF11 did not change. No association was observed with functional parameters, including the ejection fraction and the volume of both ventricles. The follow-up scans showed a reduction to baseline values (left ventricular mass 157 ± 19.3 g). CONCLUSIONS:High exercise-induced cardiac volume load for >2 months in ultra-endurance runners results in a physiological structural adaptation with no sign of adverse cardiovascular remodelling.
10.1177/2047487319885035
Impact of a 246 Km ultra-marathon running race on heart: Insights from advanced deformation analysis.
European journal of sport science
Although previous studies suggest that prolonged intense exercise such as marathon running transitorily alters cardiac function, there is little information regarding ultramarathon races. Aim of this study was to investigate the acute impact of ultra-endurance exercise (UEE) on heart, applying advanced strain imaging. Echocardiographic assessment was performed the day before and at the finish line of "Spartathlon": A 246 Km ultra-marathon running race. 2D speckle-tracking echocardiography was performed in all four chambers, evaluating longitudinal strain (LS) for both ventricles and atria. Peak strain values and temporal parameters adjusted for heart rate were extracted from the derived curves. Out of 60 participants initially screened, 27 athletes (19 male, age 45 ± 7 years) finished the race in 33:34:27(28:50:38-35:07:07) hours. Absolute values of right (RV) and left ventricular (LV) LS (RVLS -22.9 ± 3.6 pre- to -21.2 ± 3.0% post-, =0.04 and LVLS -20.9 ± 2.3 pre- to -18.8 ± 2.0 post-, =0.009) slightly decreased post-race, whereas atrial strain did not change. RV and LV LS decrease was caused mainly by strain impairment of basal regions with apical preservation. Inter-chamber relationships assessed through RV/LV, LV/LA, RV/RA and RA/LA peak values' ratios remained unchanged from pre to post-race. Finally, UEE caused an extension of the systolic phase of cardiac cycle with concomitant diastole reduction (<0.001 for all strain curves). Conclusively, ventricular LS strain as well as effective diastolic period slightly decreased, whereas atrial strain and inter-chamber relationships remained unchanged after running a 246-km-ultra-marathon race. These changes may be attributed to concomitant pre- and afterload alterations following UEE.
10.1080/17461391.2021.1930194
The athlete's heart: allometric considerations on published papers and relation to cardiovascular variables.
European journal of applied physiology
To evaluate the morphology of the "athlete's heart", left ventricular (LV) wall thickness (WT) and end-diastolic internal diameter (LVIDd) at rest were addressed in publications on skiers, rowers, swimmers, cyclists, runners, weightlifters (n = 927), and untrained controls (n = 173) and related to the acute and maximal cardiovascular response to their respective disciplines. Dimensions of the heart at rest and functional variables established during the various sport disciplines were scaled to body weight for comparison among athletes independent of body mass. The two measures of LV were related (r = 0.8; P = 0.04) across athletic disciplines. With allometric scaling to body weight, LVIDd was similar between weightlifters and controls but 7%-15% larger in the other athletic groups, while WT was 9%-24% enlarged in all athletes. The LVIDd was related to stroke volume, oxygen pulse, maximal oxygen uptake, cardiac output, and blood volume (r = ~ 0.9, P < 0.05), while there was no relationship between WT and these variables (P > 0.05). In conclusion, while cardiac enlargement is, in part, essential for the generation of the cardiac output and thus stroke volume needed for competitive endurance exercise, an enlarged WT seems important for the development of the wall tension required for establishing normal arterial pressure in the enlarged LVIDd.
10.1007/s00421-024-05449-8
A Statistical Timetable for the Sub-2-Hour Marathon.
Angus Simon D
Medicine and science in sports and exercise
INTRODUCTION:Breaking the sub-2-h marathon in an official event has attracted growing interest in recent times with commercial and international momentum building. Here it is shown that predicting how likely and when the sub-2-h barrier will be broken are statistically coupled considerations. METHODS:Using a nonlinear limiting exponential model and calculating prediction intervals, a statistical timetable for the sub-2-h event is produced over a range of likelihoods. RESULTS:At the benchmark odds level (1 in 10, or 10% likely), the expected sub-2-h arrival time is found to be May 2032. By estimating the model for male and female world record progressions, I find that limiting marathon times for males and females (at 1 in 10) are 1 h 58 min 5 s and 2 h 5 min 31 s, respectively. These times equate to a performance gap of 2.9% and 8.6%, respectively. The male estimate has remarkable similarity (~7 s) to Joyner's 1991 limiting human physiological estimate. Finally, I provide an estimate of the equivalent "sub-2-h" threshold for females and argue that a threshold of 130 min ("sub-130") could be an appropriate choice. CONCLUSION:The study is the first to address all three related aspects of world record marathon performance (sub-2 h, limits, gender equivalence) in a single, unified modeling framework and provides many avenues for further exploration and insight.
10.1249/MSS.0000000000001928
Themes and trends in marathon performance research: a comprehensive bibliometric analysis from 2009 to 2023.
Frontiers in physiology
When marathon runners break the 2-h barrier at the finishing line, it attracts global attention. This study is aimed to conduct a bibliometric analysis of publications in the field of marathon running, analyze relevant research contributors, and visualize the historical trends of marathon performance research over the past 15 years. On 8 December 2023, we extracted high-quality publication data from the Web of Science Core Collection spanning from 1 January 2009 to 30 November 2023. We conducted bibliometric analysis and research history visualization using the R language packages biblioshiny, VOSviewer, and CiteSpace. A total of 1,057 studies were published by 3,947 authors from 1,566 institutions across 63 countries/regions. USA has the highest publication and citation volume, while, the University of Zurich being the most prolific research institution. Keywords analysis revealed several hotspots in marathon research over the past 3 years: (1) physiology of the elite marathon runners, (2) elite marathon training intensity and pacing strategies, (3) nutritional strategies for elite marathon runners, (4) age and sex differences in marathon performance, (5) recovery of inflammatory response and muscle damage. This study presents the first comprehensive bibliometric analysis of marathon performance research over the past 15 years. It unveils the key contributors to marathon performance research, visually represents the historical developments in the field, and highlights the recent topical frontiers. The findings of this study will guide future research by identifying potential hotspots and frontiers.
10.3389/fphys.2024.1388565
Physiology and Pathophysiology in Ultra-Marathon Running.
Knechtle Beat,Nikolaidis Pantelis T
Frontiers in physiology
In this overview, we summarize the findings of the literature with regards to physiology and pathophysiology of ultra-marathon running. The number of ultra-marathon races and the number of official finishers considerably increased in the last decades especially due to the increased number of female and age-group runners. A typical ultra-marathoner is male, married, well-educated, and ~45 years old. Female ultra-marathoners account for ~20% of the total number of finishers. Ultra-marathoners are older and have a larger weekly training volume, but run more slowly during training compared to marathoners. Previous experience (e.g., number of finishes in ultra-marathon races and personal best marathon time) is the most important predictor variable for a successful ultra-marathon performance followed by specific anthropometric (e.g., low body mass index, BMI, and low body fat) and training (e.g., high volume and running speed during training) characteristics. Women are slower than men, but the sex difference in performance decreased in recent years to ~10-20% depending upon the length of the ultra-marathon. The fastest ultra-marathon race times are generally achieved at the age of 35-45 years or older for both women and men, and the age of peak performance increases with increasing race distance or duration. An ultra-marathon leads to an energy deficit resulting in a reduction of both body fat and skeletal muscle mass. An ultra-marathon in combination with other risk factors, such as extreme weather conditions (either heat or cold) or the country where the race is held, can lead to exercise-associated hyponatremia. An ultra-marathon can also lead to changes in biomarkers indicating a pathological process in specific organs or organ systems such as skeletal muscles, heart, liver, kidney, immune and endocrine system. These changes are usually temporary, depending on intensity and duration of the performance, and usually normalize after the race. In longer ultra-marathons, ~50-60% of the participants experience musculoskeletal problems. The most common injuries in ultra-marathoners involve the lower limb, such as the ankle and the knee. An ultra-marathon can lead to an increase in creatine-kinase to values of 100,000-200,000 U/l depending upon the fitness level of the athlete and the length of the race. Furthermore, an ultra-marathon can lead to changes in the heart as shown by changes in cardiac biomarkers, electro- and echocardiography. Ultra-marathoners often suffer from digestive problems and gastrointestinal bleeding after an ultra-marathon is not uncommon. Liver enzymes can also considerably increase during an ultra-marathon. An ultra-marathon often leads to a temporary reduction in renal function. Ultra-marathoners often suffer from upper respiratory infections after an ultra-marathon. Considering the increased number of participants in ultra-marathons, the findings of the present review would have practical applications for a large number of sports scientists and sports medicine practitioners working in this field.
10.3389/fphys.2018.00634
Does Running Increase the Risk of Hip and Knee Arthritis? A Survey of 3804 Marathon Runners.
Sports health
BACKGROUND:Long-distance running is a popular form of cardiovascular exercise with many well-described health benefits, from improving heart health to the management of obesity, diabetes, and mental illness. The impact of long-distance running on joint health in recreational runners, however, remains inconclusive. HYPOTHESIS:The prevalence of osteoarthritis in runners is not associated with an athlete's running-related history, including the number of marathons completed, cumulative years of running, average weekly mileage, and average running pace. STUDY DESIGN:Prospective cohort study. LEVEL OF EVIDENCE:Level 3. METHODS:A survey was distributed to all participants registered for the 2019 or 2021 Chicago marathon (n = 37,917). Surveys collected runner demographics and assessed for hip/knee pain, osteoarthritis, family history, surgical history, and running-related history. Running history included the number of marathons run, number of years running, average running pace, and average weekly mileage. The overall prevalence of osteoarthritis was identified, and a multivariable logistic regression model was used to identify variables associated with the presence of hip and/or knee osteoarthritis. RESULTS:Surveys were completed by 3804 participants (response rate of 10.0%). The mean age was 43.9 years (range, 18-83 years) and participants had completed on average 9.5 marathons (median, 5 marathons; range, 1-664 marathons). The prevalence of hip and/or knee arthritis was 7.3%. A history of hip/knee injuries or surgery, advancing age, family history, and body mass index (BMI) were risk factors for arthritis. Cumulative number of years running, number of marathons completed, weekly mileage, and mean running pace were not significant predictors for arthritis. The majority (94.2%) of runners planned to run another marathon, despite 24.2% of all participants being told by a physician to do otherwise. CONCLUSION:From this largest surveyed group of marathon runners, the most significant risk factors for developing hip or knee arthritis were age, BMI, previous injury or surgery, and family history. There was no identified association between cumulative running history and the risk for arthritis.
10.1177/19417381231190876
Heart Rate Does Not Reflect the %VO in Recreational Runners during the Marathon.
International journal of environmental research and public health
Exercise physiologists and coaches prescribe heart rate zones (between 65 and 80% of maximal heart rate, HR) during a marathon because it supposedly represents specific metabolic zones and the percentage of V˙O below the lactate threshold. The present study tested the hypothesis that the heart rate does not reflect the oxygen uptake of recreational runners during a marathon and that this dissociation would be more pronounced in the lower performers' group (>4 h). While wearing a portable gas exchange system, ten male endurance runners performed an incremental test on the road to determine V˙O, HR, and anaerobic threshold. Two weeks later, the same subjects ran a marathon with the same device for measuring the gas exchanges and HR continuously. The %HR remained stable after the 5th km (between 88% and 91%, = 0.27), which was not significantly different from the %HR at the ventilatory threshold (89 ± 4% vs. 93 ± 6%, = 0.12). However, the %V˙O and percentage of the speed associated with V˙O decreased during the marathon (81 ± 5 to 74 ± 5 %V˙O and 72 ± 9 to 58 ± 14 %vV˙O, < 0.0001). Hence, the ratio between %HR and %V˙O increased significantly between the 5th and the 42nd km (from 1.01 to 1.19, = < 0.001). In conclusion, pacing during a marathon according to heart rate zones is not recommended. Rather, learning about the relationship between running sensations during training and racing using RPE is optimal.
10.3390/ijerph191912451
Heart disease in marathon runners: a review.
Noakes T D
Medicine and science in sports and exercise
Thirty-six cases of heart attack or sudden death in marathon runners have been reported in the world literature to date. The mean age of the runners was 43.8 yr (range = 18 to 70), the mean years' running was 6.8 yr (range = 0.5 to 29), and the mean best standard 42.2 km marathon time was 3 h 28 min (range = 2 h 33 min to 4 h 28 min). Coronary artery disease was diagnosed either clinically, angiographically, or at autopsy in 27 runners (75%), two of whom also had histological evidence of hypertrophic cardiomyopathy. Seventy-one percent of the runners with coronary artery disease had premonitory symptoms, and most ignored such symptoms and continued to train or race. Fifty percent of all cardiac events occurred either during or within 24 h of competitive running events or long training runs. The marathon running population does not constitute solely persons with excellent cardiovascular health. Marathon runners, especially those with a family history of heart disease and other coronary risk factors, should not consider themselves immune to either sudden death or to coronary heart disease and should seek medical advice immediately if they develop any symptoms suggestive of ischemic heart disease. Physicians should not assume that "physically fit" marathon runners cannot have serious, life-threatening cardiac disease.