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Concept: Ultramarathon

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Ultramarathon runners commonly believe that sodium replacement is important for prevention of muscle cramping, dehydration, hyponatremia, and nausea during prolonged continuous exercise. The purpose of this study was to measure total sodium intake to determine if these beliefs are supported.

Concepts: Prevention, Real number, Ultramarathon

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Debilitating gastrointestinal symptoms (GIS) and dermatological injuries (DI) are common during and after endurance events and have been linked to performance decrements, event withdrawal, and issues requiring medical attention. The study aimed to determine whether GIS and DI affect food and fluid intake, and nutritional and hydration status, of ultramarathon runners during multi-stage (MSUM) and 24-h continuous (24 h) ultramarathons.

Concepts: Medicine, Gastroenterology, Ultramarathon

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Worldwide female participation in ultra-endurance events may place them at risk for the female athlete triad (FAT). The study objectives were to establish triad knowledge, occurrence of disordered eating and triad risk amongst participants of the 2014 89-km Comrades Marathon event.

Concepts: Participation, Ultramarathon, Comrades Marathon

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Ultramarathons comprise any sporting event involving running longer than the traditional marathon length of 42.195 km (26.2 miles). Studies on ultramarathon participants can investigate the acute consequences of ultra-endurance exercise on inflammation and cardiovascular or renal consequences, as well as endocrine/energetic aspects, and examine the tissue recovery process over several days of extreme physical load. In a study published in BMC Medicine, Schütz et al. followed 44 ultramarathon runners over 4,487 km from South Italy to North Cape, Norway (the Trans Europe Foot Race 2009) and recorded daily sets of data from magnetic resonance imaging, psychometric, body composition and biological measurements. The findings will allow us to better understand the timecourse of degeneration/regeneration of some lower leg tissues such as knee joint cartilage, to differentiate running-induced from age-induced pathologies (for example, retropatelar arthritis) and finally to assess the interindividual susceptibility to injuries. Moreover, it will also provide new information about the complex interplay between cerebral adaptations/alterations and hormonal influences resulting from endurance exercise and provide data on the dose-response relationship between exercise and brain structure/function. Overall, this study represents a unique attempt to investigate the limits of the adaptive response of human bodies.Please see related article: http://www.biomedcentral.com/1741-7015/10/78.

Concepts: Brain, Cartilage, Magnetic resonance imaging, Knee, Tissue, Running, Marathon, Ultramarathon

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Background In contrast to the well-accepted benefits of moderate exercise, recent research has suggested potential deleterious effects of repeated marathon running on the cardiovascular system. We thus performed a comprehensive analysis of markers of subclinical vascular damage in a cohort of runners having finished multiple marathon races successfully. Design This was a prospective, observational study. Methods A total of 97 healthy male Munich marathon participants (mean age 44 ± 10 years) underwent detailed training history, cardiopulmonary exercise testing for assessment of peak oxygen uptake, ultrasound for assessment of intima-media-thickness as well as non-invasive assessments of ankle-brachial index, augmentation index, pulse wave velocity and reactive hyperaemia index. Results Runners had previously completed a median of eight (range 1-500) half marathons, six (1-100) full marathons and three (1-40) ultramarathons; mean weekly and annual training volumes were 59 ± 23 and 1639 ± 979 km. Mean peak oxygen uptake was 50 ± 8 ml/min/kg, and the Munich marathon was finished in 3:45 ± 0:32 h. Runners showed normal mean values for intima-media-thickness (0.60 ± 0.14 mm), ankle-brachial index (1.2 ± 0.1), augmentation index (17 ± 13%), pulse wave velocity (8.7 ± 1.4 cm/s) and reactive hyperaemia index (1.96 ± 0.50). Age was significantly and independently associated with intima-media-thickness ( r = 0.531; p < 0.001), augmentation index ( r = 0.593; p < 0.001) and pulse wave velocity ( r = 0.357; p < 0.001). However, no independent associations of peak oxygen uptake, marathon finishing time, number of completed races or weekly and annual training km with any of the vascular parameters were observed. Conclusions In this cohort of healthy male runners, running multiple marathon races did not pose an additional risk factor for premature subclinical vascular impairment beyond age.

Concepts: Running, Marathon, Ultramarathon, Half marathon

3

Ultra-endurance challenges were once the stuff of legend isolated to the daring few who were driven to take on some of the greatest physical endurance challenges on the planet. With a growing fascination for major physical challenges during the nineteenth century, the end of the Victorian era witnessed probably the greatest ultra-endurance race of all time; Scott and Amundsen’s ill-fated race to the South Pole. Ultra-endurance races continued through the twentieth century; however, these events were isolated to the elite few. In the twenty-first century, mass participation ultra-endurance races have grown in popularity. Endurance races once believed to be at the limit of human durability, i.e. marathon running, are now viewed as middle-distance races with the accolade of true endurance going to those willing to travel significantly further in a single effort or over multiple days. The recent series of papers in Extreme Physiology & Medicine highlights the burgeoning research data from mass participation ultra-endurance events. In support of a true ‘mass participation’ ethos Knetchtle et al. reported age-related changes in Triple and Deca Iron-ultra-triathlon with an upper age of 69 years! Unlike their shorter siblings, the ultra-endurance races appear to present larger gender differences in the region of 20% to 30% across distance and modality. It would appear that these gender differences remain for multi-day events including the ‘Marathon des Sables’; however, this gap may be narrower in some events, particularly those that require less load bearing (i.e. swimming and cycling), as evidenced from the ‘Ultraman Hawaii’ and ‘Swiss Cycling Marathon’, and shorter (a term I used advisedly!) distances including the Ironman Triathlon where differences are similar to those of sprint and endurance distances i.e. c. 10%. The theme running through this series of papers is a continual rise in participation to the point where major events now require selection races to remain within reasonable limits. With the combination of distance and environment placing a significant physiological bordering on pathophysiological burden on the participants of such events, one question remains: Are we destined for another Scott vs. Amundsen? How long is too long?

Concepts: Running, Marathon, South Pole, North Pole, Triathlon, Ironman Triathlon, Ultramarathon, Multiday race

3

Little is known about exercise habits of those who compete in foot races longer than the standard 42-km marathon distance. The purpose of this work was to describe the past-year and lifetime exercise patterns of a large cohort of ultramarathon runners. Information on exercise history was collected on 1,345 current and former ultramarathon runners as baseline data for participation in a longitudinal observational study. Median age at the first ultramarathon was 36 years, and the median number of years of regular running prior to the first ultramarathon was 7 (interquartile range 3-15). Age at first ultramarathon did not changed across the past several decades, but there was evidence of an inverse relationship (r=-0.13, p<0.0001) between number of years of regular running prior to the first ultramarathon and calendar year. The active ultramarathon runners (n=1,212) had a prior year median running distance of 3,347 km, which was minimally related to age (r=-0.068, p=0.018), but mostly related to their longest ultramarathon competition of the year (p<0.0001). Running injuries represented the most common reason for discontinuation of regular running, while work and family commitments were reported as the main reasons for not running an ultramarathon in the prior year among those who were regularly running and intending to run ultramarathons again. We conclude that runners tend to be well into adulthood and with several years of running experience before running their first ultramarathon, but 25% have only been regularly running for 3 years or less at the time of their first ultramarathon.

Concepts: Scientific method, Longitudinal study, Median, Interquartile range, Running, Marathon, Ultramarathon

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During the 4,487 km ultra marathon TransEurope-FootRace 2009 (TEFR09), runners showed catabolism with considerable reduction of body weight as well as reversible brain volume reduction. We hypothesized that ultra marathon athletes might have developed changes to grey matter (GM) brain morphology due to the burden of extreme physical training. Using voxel-based morphometry (VBM) we undertook a cross sectional study and two longitudinal studies.

Concepts: Longitudinal study, Cross-sectional study, Mass, Ultramarathon

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Anecdotal claims suggest that an increasing number of ultra-marathoners purposely undertake chronic low-carbohydrate (CHO) / ketogenic diets while training, and race with very low CHO intakes, as a way to maximize fat oxidation and improve performance. However, very little empirical evidence exists on specific fueling strategies that elite ultra-marathoners undertake to maximize race performance. Therefore, the purpose was to characterize both pre and during race nutrition habits of elite ultra-marathon runners. Three world-class veteran male ultra-runners (mean±SD; age 35±2y; mass 59.5±1.7kg; 16.7±2.5h 100-mile best-times) agreed to complete a competition-specific nutrition intake questionnaire. Verbal and visual instructions were used to instruct the athletes on portion sizes and confirm dietary intake. Throughout 2014, the athletes competed in 16 ultramarathons with a total of eight wins, including winning the prestigious Western States Endurance Run 100-miler (14.9h). The average pre-race breakfast contained 70±16, 29±20 and 21±8g of CHO, protein and fat, respectively. Throughout 100-mile races, athletes consumed an average of 1162±250g of CHO (71±20g/h), with minor fat and protein intakes. This resulted in caloric intakes totaling 5530±1673 kcals (333±105 kcals/h). Athletes also reported consuming 912±322mg of caffeine and 6.9±2.4g of sodium. Overall, commercial products accounted for 93±12% of energy intake. In conclusion, these world-class ultra-runners practice fuelling strategies that maximize CHO intake. Despite having limited professional nutritional input into their fueling approaches, all athletes' individual intakes for CHO and sodium are congruent with contemporary evidence-based recommendations.

Concepts: Protein, Metabolism, Nutrition, Fat, Diet, Ketogenic diet, Ultramarathon, Western States Endurance Run

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Participants in the Ultrarunners Longitudinal TRAcking (ULTRA) Study were asked to answer “yes” or “no” to the question “If you were to learn, with absolute certainty, that ultramarathon running is bad for your health, would you stop your ultramarathon training and participation?” Among the 1349 runners, 74.1% answered “no”. Compared with those answering “yes”, they were younger (p < 0.0001), less likely to be married (p = 0.019), had less children (p = 0.0095), had a lower health orientation (p < 0.0001) though still high, and higher personal goal achievement (p = 0.0066), psychological coping (p < 0.0001) and life meaning (p = 0.0002) scores on the Motivations of Marathoners Scales. Despite a high health orientation, most ultramarathon runners would not stop running if they learned it was bad for their health as it appears to serve their psychological and personal achievement motivations and their task orientation such that they must perceive enhanced benefits that are worth retaining at the risk of their health.

Concepts: Psychology, Cognition, Question, Learning, Answer, Uncertainty, Marathon, Ultramarathon