Ultra-endurance Triathlon Research Articles

Ultra-Endurance triathlon competition shifts fecal metabolome independent of changes to microbiome composition.

Understanding changes to gut microbiota composition and metabolic output in response to acute exercise may be necessary for understanding the mechanisms mediating the long-term health and performance benefits of exercise. Our primary objective was to characterize acute changes in the fecal microbiome and metabolome following participation in an ultra-endurance (3.9 km swim, 180.2 km bike, 42.2 km run) triathlon. An exploratory aim was to determine associations between athlete-specific factors [race performance (i.e., completion time) and lifetime years of endurance training] with pre-race gut microbiota and metabolite profiles. Stool samples from 12 triathletes (9 males/3 females; 43 ± 14 yr, 23 ± 2 kg/m2) were collected ≤48 h before and the first bowel movement following race completion. Intra- and inter-individual diversity of bacterial species and individual bacterial taxa were unaltered following race completion (P > 0.05). However, significant reductions (P < 0.05) in free and secondary bile acids [deoxycholic acid (DCA), 12-keto-lithocholic acid (12-ketoLCA)] and short-chain fatty acids (butyric and pivalic acids), and significant increases (P < 0.05) in long-chain fatty acids (oleic and palmitoleic acids) were observed. Exploratory analyses revealed several associations between pre-race bacterial taxa and fecal metabolites with race performance and lifetime history of endurance training (P < 0.05). These findings suggest that 1) acute ultra-endurance exercise shifts microbial metabolism independent of changes to community composition and 2) athlete performance level and training history relate to resting-state gut microbial ecology.NEW & NOTEWORTHY This is the first study to characterize acute changes in gut microbial ecology and metabolism following an ultra-endurance triathlon. We demonstrate changes in gut microbial community function, but not structure, as well as several associations between gut microbiome and fecal metabolome characteristics with race completion time and lifetime history of endurance training. These data add to a small but growing body of literature seeking to characterize the acute and chronic effects of exercise on the gut microbial ecosystem.

Medical Encounters and Treatment Outcomes in Ironman-Distance Triathlon.

This study aimed to examine the injury and illness characteristics, treatments, and outcomes at elite ultraendurance triathlon events. We quantified participant demographics, injury types, treatments, and disposition for medical encounters at 27 Ironman-distance triathlon championships from 1989 to 2019. We then calculated the likelihood of concurrent medical complaints in each encounter. We analyzed 10,533 medical encounters among 49,530 race participants for a cumulative incidence of 221.9/1000 participants (95% confidence interval [CI] = 217.7-226.2). Younger (<35 yr; 259.3/1000, 95% CI = 251.6-267.2) and older athletes (70+ yr; 254.0/1000, 95% CI = 217.8-294.4) presented to the medical tent at higher rates than middle-age adults (36-69 yr; 180.1/1000, 95% CI = 175.4-185.0). Female athletes also presented at higher rates when compared with males (243.9/1000, 95% CI = 234.9-253.2 vs 198.0/1000, 95% CI = 193.4-202.6). The most common complaints were dehydration (438.7/1000, 95% CI = 426.2-451.6) and nausea (400.4/1000, 95% CI = 388.4-412.6). Intravenous fluid was the most common treatment (483/1000; 95% CI = 469.8-496.4). Of the athletes who received medical care, 116.7/1000 (95% CI = 110.1-123.4) did not finish the race, and 17.1/1000 (95% CI = 14.7-19.8) required hospital transport. Athletes rarely presented with an isolated medical condition unless their injury was dermatologic or musculoskeletal in nature. Ultraendurance triathlon events have high rates of medical encounters among female athletes, as well as both younger and older age categories. Gastrointestinal and exertional-related symptoms are among the most common complaints. Intravenous infusions were the most common treatment after basic medical care. Most athletes entering the medical tent finished the race, and a small percentage were dispatched to the hospital. A more thorough understanding of common medical occurrences, including concurrent presentations and treatments, will allow for improved care and optimal race management.

Sleep Duration Correlates With Performance in Ultra-Endurance Triathlon.

The relationship between sleep duration, sleep quality, and race completion time during each stage of a 3-day ultra-endurance triathlon (stage 1: 10-km swim, 146-km cycle; stage 2: 276-km cycle; and stage 3: 84.4-km run) was investigated. Seventeen triathletes partook in sleep analysis throughout the ultra-endurance multiday triathlon using an actigraphy wristband. The participants wore the band to record objective sleep outcomes for approximately 4days (1-2d prerace, 3 race days, and 1d postrace), except while racing. The total sleep time (TST; prerace: 414.1 [95.3]min, prestage 1: 392.2 [138.3]min, prestage 2: 355.6 [62.5]min, and prestage 3: 299.7 [107.0]min) significantly decreased over time (P < .05). Significant Pearson moment-product correlations were found between TST and subsequent race-day performance for race stage 1 (r = -.577; P = .019) and stage 3 (r = -.546; P = .035), with further analysis revealing that TST explained 33% and 30% of the variation in performance for stages 1 and 3, respectively. During a 3-day ultra-endurance triathlon, the TST was reduced and had a significant negative correlation to exercise performance, indicating that sleep loss was associated with slower performances. Sleep onset latency, wake episodes, and sleep efficiency did not significantly change over the course of this investigation, which may stem from the close proximity of exercise to sleep.

Circulating Brain Derived Neurotropic Factor (BDNF) In Response To Three-day Ultra-endurance Racing

Cardiovascular exercise is known to exert a variety of positive physiological and psychological benefits on neurocognitive function, glucose and fatty acid metabolism, and muscle recovery. Many of these effects are thought to be mediated by brain derived neurotropic factor (BDNF), a neurotropin produced both centrally and peripherally. The fate of BDNF during prolonged endurance exercise is unknown and may be implicated to mitigate potential negative consequences to ultra-endurance racing. PURPOSE: To investigate the effects of a three-day ultra-endurance triathlon on serum BDNF concentrations pre- and post-race. METHODS: Twenty triathletes (age: 40 ± 8.8 yrs) who competed in the 2015 (N=13 men, 3 women) and 2017 (N=3 men, 1 woman) Ultraman Florida triathlon participated in the present study. Blood samples were collected 24-36 hrs pre-race and within 12 hrs post-race. Serum BDNF levels were measured via ELISA. A paired sample t-test was used to evaluate differences between pre- and post-race BDNF concentrations. Values are reported as mean ± SD with significance accepted as p<0.05. RESULTS: BDNF significantly increased from pre- to post- race (0.17 ± 0.9 pg/mL vs. 0.23 ± 0.14 pg/mL; +9.6%; p<0.05). CONCLUSIONS: For the first time, BDNF is shown to significantly increase after a three-day ultra-endurance race. These findings may indicate that BDNF concentrations are elevated to potentially counteract any negative consequences derived from ultra-endurance exercise. The influence of both duration and intensity of exercise on BDNF concentrations need to be further elucidated due to its array of positive implications on cognitive and physical function and recovery from prolonged endurance exercise. Supported by the International Society of Sports Nutrition and Florida State University.

Ultra-endurance triathlon performance and markers of whole-body and gut-specific inflammation.

To examine the influence of the Ultraman Florida triathlon (3days of non-continuous racing; stage 1: 10km swim and 144.8km cycle; stage 2: 275.4km cycle; stage 3: 84.4km run) on circulating plasma concentrations of whole-body (C-reactive protein (CRP), interleukin (IL)-6 (IL-6), and IL-10 and surrogate gut-specific inflammatory markers (IL-17 and IL-23), and determine whether these variables are associated with performance. Eighteen triathletes (N = 18; 15 men, 3 women; age: 37 ± 8 yrs) were evaluated at baseline and post-race for circulating concentrations of CRP, IL-6, IL-10, IL-17, and IL-23. Blood samples were drawn two days prior to stage 1 (1600h) and one day after stage 3 (1200h). Plasma CRP significantly increased from baseline (1985.8 ± 5962.3ng/mL) to post-race (27,013.9 ± 12,888.8ng/mL, p < 0.001, 13-fold increase). Both plasma IL-6 and IL-10 did not significantly change from baseline to post-race. Baseline and post-race concentrations of IL-17 and IL-23 were below detectable limits. Pearson's correlation between mean finish time and post-race IL-10 revealed a significant positive correlation (r = 0.54, p < 0.05). Our results suggest that cytokines such as IL-6 and IL-10 involved in the inflammatory response return to near-baseline concentrations rapidly even after ultra-endurance events of extreme duration. The absence of IL-17 and IL-23 may suggest positive gut adaptations from ultra-endurance training. A significant positive correlation between post-race IL-10 concentrations and mean finish time may indicate that a relationship between anti-inflammatory responses and performance exists.

The age of peak performance in women and men duathletes - The paradigm of short and long versions in "Powerman Zofingen".

PurposeThe age of peak performance (APP) has been studied extensively in various endurance and ultra-endurance sports; however, less information exists in regard to duathlon (ie, Run1, Bike, and Run2). The aim of the present study was to assess the APP of duathletes competing either in a short (ie, 10 km Run1, 50 km Bike, and 5 km Run2) or a long distance (ie, 10 km Run1, 150 km Bike, and 30 km Run2) race.Participants and methodsWe analyzed 6,671 participants (women, n=1,037, age 36.6±9.1 years; men, n=5,634, 40.0±10.0 years) in “Powerman Zofingen” from 2003 to 2017.ResultsConsidering the finishers in 5-year age groups, in the short distance, a small main effect of sex on race time was observed (p<0.001, η2 =0.052) with men (171.7±20.9 min) being faster than women (186.0±21.5 min) by −7.7%. A small main effect of age group on race was shown (p<0.001, η2 =0.049) with 20–24 years being the fastest and 70–74 years the slowest. No sex × age group interaction was found (p=0.314, η2 =0.003). In the long distance, a small main effect of sex on race time was observed (p<0.001, η2 =0.021) with men (502.8±56.8 min) being faster than women (544.3±62.8 min) by −7.6%. A large main effect of age group on race time was shown (p<0.001, η2 =0.138) with age group 25–29 years the fastest and age group 70–74 years the slowest. A small sex × age group interaction on race time was found (p<0.001, η2 =0.013) with sex difference ranging from −22.4% (15–19 age group) to −6.6% (30–34 age group).ConclusionBased on these findings, it was concluded an older APP in the long than in the short distance was seen in “Powerman Zofingen.” This indicates that APP in duathlon follows a similar trend as in endurance and ultra-endurance running and triathlon, ie, the longer the distance, the older the APP.

The Effect of Total Sleep Time on Ultra-Endurance Triathlon Performance

PURPOSE: The primary purpose was to determine the effect of sleep time on performance during a 3-day multistage ultra-endurance triathlon (stage 1: 10km swim, 144.8km bike; stage 2: 275.8 km bike; stage 3: 84.4km run). Secondarily, we determined if performance time predicts sleep time. METHODS: Eighteen triathletes (age: 37±7.9y; height: 175±7cm; weight: 70±9kg) partook in sleep analysis pre, during, and post triathlon using an actigraphy wrist band. Participants wore the band to record sleep time for five days (1-2 days pre-race, 3 race days, 1-day post-race), except during racing. Bands were collected before each stage to download the previous night’s data, then re-distributed after each stage. Performance times were recorded after each stage, and following total completion of the race. The data was analyzed via linear regression. RESULTS: Total sleep time (mean±SD; pre-race: 393.9±81.1 min, pre-stage 1: 342±90.2min, pre-stage 2: 347.5±54.6min, pre-stage 3: 299.7±107.0min, post-race: 308.8±86.3min) significantly decreased over time (P<0.05). Sleep time predicted performance in multiple stages. Specifically, pre-stage 3 sleep time explained 30% and 43% of the variation in stage 3 performance (R2=0.30, p=0.035), and total finishing time (R2=0.43, p=0.008). Performance time also predicted sleep time. Specifically, stage 1 performance explained 37% and 47% of the variation in pre-stage 2 sleep time (R2=0.37, p=0.010), and pre-stage 3 sleep time (R2=0.47, p=0.005). Stage 2 performance explained 39% the variation in pre-stage 3 sleep time (R2=0.39, p=0.014). Total race sleep time (Pre-stage 1, 2, and 3) was averaged; 33% of the variation in total finishing time can be predicted by average total racing sleep time (R2=0.33, p=0.015). No additional relationships were seen. A cutoff value was found at 401.6 min of average total race-night sleep time, indicating the top 25% of race finishers slept for ≥401.6 min. CONCLUSIONS: During a multistage ultra-endurance triathlon, performance time can be predicted by sleep time the night before. In addition, faster performance times during each stage predicts more sleep time. Based on our results, average total race-night sleep time of roughly 402 min (6.7h/night) leads to faster finishing time in the Ultraman Florida. This study was supported by FSU and FatigueScience.

Assessing the Impact of Probiotic Supplementation and Caloric Periodization on Ultra-endurance Performance and Gastrointestinal Symptoms

Beneficial use of probiotic (PRO) interventions on gastrointestinal endotoxemia (GE) prior to an ultra-endurance triathlon has been previously demonstrated. The prevalence of GE (and whether PRO strategies minimise gastrointestinal (GI) symptoms) relating to multi-day ultra-events is less known. Understanding if nutritional periodization strategies confer similar GI benefits also warrants investigation. PURPOSE: To assess the impact of probiotic supplementation and caloric periodization prior to an extreme ultra-marathon on GI symptoms and race performance. METHODS: Thirty-eight healthy participants were recruited from entrants of the 2015 Marathon Des Sables (age: 42±9yrs; weight: 77.71±10.31kg; VO2max: 52.58±8.66mL·kg·min-1), and randomly assigned to either: PRO (100mg.d-1 capsulated Lactobacillus acidophilus); CP (caloric periodization of 500kcal above habitual intake on alternate days) or control (CON) for 12 weeks pre-race. Plasma lipopolysaccharides (LPS) via Limulus Amebocyte Lysate chromogenic endotoxin quantification were determined at baseline, pre and post-race. Participants graded duration and severity of GI symptoms through daily questionnaires. Performance times were obtained from accumulated race tracking. Data presented as mean±SE. RESULTS: Race times (hrs:mins) were 41:28±2:31, 45:12±2:05 and 50:43 ±4:38 for PRO, CP and CON respectively (p>0.05). Overall LPS significantly increased from baseline (10.08±0.53pg.ml-1) to pre-race (13.12±0.74pg.ml-1; p=0.001). Delta LPS pre-race was not different between groups (PRO: 2.94±1.11pg.ml-1; CP: 3.71±1.28pg.ml-1; CON: 2.32±1.26pg.ml-1; p>0.05). Similarly, delta LPS post-race was not different, despite greater reductions in both intervention groups (PRO: -4.57±1.93pg.ml-1; CP: -6.95±1.84pg.ml-1; CON: -2.16±2.21pg.ml-1; p>0.05). GI symptom count favoured PRO (21.8%) compared with CP (41.6%) and CON (36.6%) respectively (p=0.001), although no differences for GI symptom index were reported between groups (p>0.05). CONCLUSIONS: Moderate GE was evident in a UK cohort undertaking a multi-day ultra-marathon. PRO use did not significantly impact on GE prevalence, despite evidence of reduced GI symptoms. Caloric periodization appeared to favour GE recovery post-race, but was not deemed significant.

Fluid retention, muscle damage, and altered body composition at the Ultraman triathlon.

The primary purpose of this investigation was to determine the effects of participation in a 3-day multistage ultraendurance triathlon (stage 1 = 10 km swim, 144.8 km bike; stage 2 = 275.4 km bike; stage 3 = 84.4 km run) on body mass and composition, hydration status, hormones, muscle damage, and blood glucose. Eighteen triathletes (mean ± SD; age 41 ± 7.5 years; height 175 ± 9 cm; weight 73.5 ± 9.8 kg; male n = 14, female n = 4) were assessed before and after each stage of the race. Body mass and composition were measured via bioelectrical impedance, hydration status via urine specific gravity, hormones and muscle damage via venous blood draw, and blood glucose via fingerstick. Following the race, significant changes included reductions in body mass (qualified effect size: trivial), fat mass (moderate), and percent body fat (small); increases in percent total body water (moderate) and urine specific gravity (large); and unchanged absolute total body water and fat-free mass. There were also extremely large increases in creatine kinase, C-reactive protein, aldosterone and cortisol combined with reductions in testosterone (small) and the testosterone:cortisol ratio (moderate). There were associations between post-race aldosterone and total body water (r = -0.504) and changes in cortisol and fat-free mass (r = -0.536). Finally, blood glucose increased in a stepwise manner prior to each stage. Participation in Ultraman Florida leads to fluid retention and dramatic alterations in body composition, muscle health, hormones, and metabolism.

Saccharide Composition of Carbohydrates Consumed during an Ultra-endurance Triathlon

Objective: Ingesting a mix of glucose and fructose during exercise increases exogenous carbohydrate oxidation while minimizing gastrointestinal (GI) distress. Several studies have suggested that a glucose-to-fructose ratio of 1.2:1 to 1:1 is optimal. No studies have quantified saccharides consumed during a nonsimulated endurance event. The aim of this investigation was to quantify saccharide sources used during an ultra-endurance triathlon and provide a resource for athletes desiring to manipulate the saccharide content of carbohydrate consumed during training and competition.Methods: Participant self-report and direct measurement were used to assess foods and beverages consumed during an ultra-endurance (70.3-mile) triathlon. Manufacturer-supplied information, high-performance liquid chromatography, and the US Department of Agriculture Food Database were used to quantify saccharide profiles of foods and beverages. Participants reported GI distress during the run on a 0–10 scale. A subanalysis examined associations between saccharides and GI distress among participants consuming ≥ 50 g·h−1 of carbohydrate during the swim and cycle.Results: Fifty-four participants (43 men) used 80 foods and beverages with a unique saccharide profile. Of total carbohydrate, median proportions as glucose, fructose, and sucrose were 64%, 5%, and 10%, and only 7 foods (8.8%) had a glucose-to-fructose ratio of 1.2:1 to 1:1. The median glucose-to-fructose ratio of carbohydrate ingested was 2.9:1 (2.2:1–5.3:1). Twenty participants consumed ≥ 50 g·h−1 of carbohydrate during the swim and cycle, and significant correlations with incident GI distress at mile 1 of the run were found for glucose (r = 0.480, p = 0.032) and fructose (r = −0.454, p = 0.044).Conclusions: The majority of foods and beverages consumed during an ultra-endurance triathlon did not contain an optimal saccharide profile. Furthermore, glucose intake was associated with greater GI distress among participants consuming a high rate of carbohydrate.

Energy balance of triathletes during an ultra-endurance event.

The nutritional strategy during an ultra-endurance triathlon (UET) is one of the main concerns of athletes competing in such events. The purpose of this study is to provide a proper characterization of the energy and fluid intake during real competition in male triathletes during a complete UET and to estimate the energy expenditure (EE) and the fluid balance through the race. Methods: Eleven triathletes performed a UET. All food and drinks ingested during the race were weighed and recorded in order to assess the energy intake (EI) during the race. The EE was estimated from heart rate (HR) recordings during the race, using the individual HR-oxygen uptake (Vo2) regressions developed from three incremental tests on the 50-m swimming pool, cycle ergometer, and running treadmill. Additionally, body mass (BM), total body water (TBW) and intracellular (ICW) and extracellular water (ECW) were assessed before and after the race using a multifrequency bioimpedance device (BIA). Results: Mean competition time and HR was 755 ± 69 min and 137 ± 6 beats/min, respectively. Mean EI was 3643 ± 1219 kcal and the estimated EE was 11,009 ± 664 kcal. Consequently, athletes showed an energy deficit of 7365 ± 1286 kcal (66.9% ± 11.7%). BM decreased significantly after the race and significant losses of TBW were found. Such losses were more related to a reduction of extracellular fluids than intracellular fluids. Conclusions: Our results confirm the high energy demands of UET races, which are not compensated by nutrient and fluid intake, resulting in a large energy deficit.

Intensity profile during an ultra-endurance triathlon in relation to testing and performance.

We examined the heart rate (HR)-based intensity profile during an ultra-endurance triathlon (UET) estimated from the individual HR-oxygen uptake (˙VO2) relationship during specific graded tests, relating it to race performance. 9 male ultra-endurance triathletes completed the study. Before racing, subjects performed graded exercise tests involving cycle (C) ergometry, treadmill running (R) and free swimming (S) for peak ˙VO2 and HR at ventilatory thresholds (VT). Exercise-specific HR-˙VO2 regression equations were developed. Mean race HR was higher during S (149.2 (10.1) bpm) than during C (137.1 (5.7) bpm) and R (136.2 (10.5) bpm). During C and R, HR was below both VT (11% and 27-28%). HR differences between S and C correlated with C, R and final times. The greatest differences between S and C were related to the worst times in the next stages. These ultra-endurance triathletes performed S at a higher relative intensity, which was inversely correlated with performance in the following stages. The best predictors of final racing time (81%) were weight-adjusted ˙VO2max and HR difference between C and S. A more adequate characterization of the time pattern during the whole race, especially during S, adds new information concerning the intensity profile and cardiovascular demands of an UET race.

Spurious Hb Mass Increases Following Exercise

Sensitivity of the Athlete Blood Passport for blood doping could be improved by including total haemoglobin mass (Hb(mass)), but this measure may be unreliable immediately following strenuous exercise. We examined the stability of Hb(mass) following ultra-endurance triathlon (3.8 km swim, 180 km bike, 42.2 km run). 26 male sub-elite triathletes, 18 Racers and 8 Controls, were tested for Hb(mass) using CO re-breathing, twice 1-5 days apart. Racers were measured before and 1-3 h after the triathlon. Controls did no vigorous exercise on either test day. Serum haptoglobin concentration and urine haemoglobin concentration were measured to assess intravascular haemolysis. There was a 3.2% (p<0.01) increase in Racers' Hb(mass) from pre-race (976 g ± 14.6%, mean ±% coefficient of variation) to post-race (1 007 g ± 13.8%), as opposed to a - 0.5% decrease in Controls (pre-race 900 g ± 13.9%, post-race 896 g ± 12.4%). Haptoglobin was - 67% (p<0.01) reduced in Racers (pre-race 0.48 g / L ± 150%, post-race 0.16 g / L ± 432%), compared to - 6% reduced in Controls (pre-race 1.08 g / L ± 37%, post-race 1.02 g / L ± 37%). Decreased serum haptoglobin concentration in Racers, which is suggestive of mild intravascular blood loss, was contrary to the apparent Hb(mass) increase post-race. Ultra-endurance triathlon racing may confound the accuracy of post-exercise Hb(mass) measures, possibly due to splenic contraction or an increased rate of CO diffusion to intramuscular myoglobin.

Detraining Decreases Hbmass of Triathletes

Haemoglobin mass (Hbmass) determination using CO rebreathing may assist to detect illegal blood doping practices, however variations in Hbmass with periods of intensive training and detraining must be quantified. This study aimed to determine the effect of a 30-day period of detraining on Hbmass in ultra-endurance triathletes. 9 male recreational triathletes (29-44 years) participated in the study. Hbmass was assessed using CO rebreathing 30 days and 10 days before an ultra-endurance triathlon and after ~10, 20 and 30 days of detraining following the race. V˙O2max was assessed 10 days before the race and also after the 30-day detraining period, which consisted of an 87% reduction in training hours. After 30-days of detraining there was a 3.1% decrease in mean Hbmass from 868±99 to 840±94 g, (p=0.03), and a 4.7% decrease in mean V˙O2max from 4.83±0.29 to 4.61±0.41 L/min as well as a 2.8% increase of body mass from 75.1±6.4 to 77.1±6.1 kg and a 28% increase in skinfold total from 43.9±14.2 to 55.1±14.0 mm. Individual decreases in Hbmass following detraining would need to be considered if using Hbmass for anti-doping purposes.

Effect of a Multistage Ultraendurance Triathlon on Aldosterone, Vasopressin, Extracellular Water and Urine Electrolytes

Prolonged endurance exercise over several days induces increase in extracellular water (ECW). We aimed to investigate an association between the increase in ECW and the change in aldosterone and vasopressin in a multistage ultraendurance triathlon, the 'World Challenge Deca Iron Triathlon' with 10 Ironman triathlons within 10 days. Before and after each Ironman, body mass, ECW, urinary [Na(+)], urinary [K(+)], urinary specific gravity, urinary osmolality and aldosterone and vasopressin in plasma were measured. The 11 finishers completed the total distance of 38 km swimming, 1800 km cycling and 422 km running within 145.5 (18.8) hours and 25 (22) minutes. ECW increased by 0.9 (1.1) L from 14.6 (1.5) L prerace to 15.5 (1.9) L postrace (P < 0.0001). Aldosterone increased from 70.8 (104.5) pg/mL to 102.6 (104.6) pg/mL (P = 0.033); vasopressin remained unchanged. The increase in ECW was related neither to postrace aldosterone nor to postrace vasopressin. In conclusion, ECW and aldosterone increased after this multistage ultraendurance triathlon, but vasopressin did not. The increase in ECW and the increase in aldosterone were not associated.

Assessment of muscle fatigue after an ultra-endurance triathlon using tensiomyography (TMG)

In this study, we used tensiomyography (TMG) to assess muscle status immediately after an ultra-endurance triathlon. Maximal radial displacement or deformation of the muscle belly, contraction time, delay time, sustain time, and relaxation time were measured for both legs, and dependent t-tests were used to compare means between the beginning and end of the race. The 19 men assessed (age 37.9 ± 7.1 years; height 177.5 ± 4.6 cm; weight: 73.6 ± 6.5 kg) participated in the 2009 edition of the Lanzarote Ironman. Deterioration in the neural response was observed for contraction time (P = 0.008) and relaxation time (P = 0.011), with a moderate decrease in the response time (sustain time) and a loss in muscle stiffness (deformation of the muscle belly). The effect of muscle fatigue on the rectus femoris and biceps femoris was different. Barely any changes in contraction time, relaxation time, sustain time, and deformation of the muscle belly were observed, while only the contraction response time decreased to a significant extent (reduction in delay time; P = 0.003). The considerable loss in contractile capacity induced by a long-distance race was reflected in changes in the neuromuscular response and fluctuations in the contractile capacity of the muscle. These modifications, derived from a prolonged, exhausting effort, can be assessed in a simple, non-aggressive, non-invasive way using tensiomyography.

Serum Sodium Concentration Changes Are Related to Fluid Balance and Sweat Sodium Loss

This study determined if changes in serum sodium concentration are related to fluid balance as well as sweat sodium losses in triathletes competing in the Hawaii Ironman triathlon. Endurance trained athletes (N = 46, age = 24-67 yr) were studied during 30 min of stationary cycling at 70%-75% of HRmax in a warm outdoor laboratory (26.4 degrees C +/- 1.7 degrees C wet bulb globe temperature [WBGT], 28.3 degrees C +/- 1.2 degrees C dry bulb [DB]) 3-7 d before race day. Sweat sodium concentration was measured from absorbent patches on the forearm and scapula, and sweating rate was derived from changes in body mass. Before and after the race, serum sodium concentration, body mass, and nutritional intake during the race were also measured (N = 46). Sweating and race day comparisons and changes in serum sodium concentration were analyzed via Student's t-test, correlation, and multiple regression. In men, the change in serum sodium concentration during the race was correlated with relative sweating rate (mL.kg.h; r = -0.49, P = 0.012), rate of sweat sodium loss (mEq.kg.h; r = -0.44, P = 0.023), and body mass change (kg; r = -0.54, P = 0.005). Together, the rate of sweat sodium loss and body mass change accounted for 46% of the change in serum sodium concentration in men (R = 0.46). In women, body mass change alone was significantly correlated with the change in serum sodium concentration (r = 0.31). The rate of sodium intake (mEq.kg.h) was related to the rate of sweat sodium loss in women (mEq.kg.h; r = 0.64, P = 0.035) but not in men (r = 0.27, P = 0.486). Changes in serum sodium concentration during an ultraendurance triathlon are significantly related to interactions of fluid balance, sweat sodium loss, and sodium ingestion.

Body Composition, Energy, and Fluid Turnover in a Five-Day Multistage Ultratriathlon: A Case Study

A multistage ultraendurance triathlon over five times the Ironman distance within five consecutive days leads in one ultraendurance triathlete to minimal changes in body mass (BM; –0.3 kg), fat mass (FM; –1.9 kg), skeletal muscle mass (SM; no change), and total body water (TBW; +1.5 l). This might be explained by the continuously slower race times throughout the race every day and the positive energy balance (8,095 kcal), although he suffered an average energy deficit of –1,848 kcal per Ironman distance. The increase of TBW might be explained by the increase of plasma volume (PV) in the first 3 days. The increase of PV and TBW could be a result of an increase of sodium, which was increased after every stage. We presume that this could be the result of an increased activity of aldosterone.

Der Einfluss von zehn aufeinander folgenden Langdistanz-Triathlons auf Körperfett und Muskelmasse – World Challenge Deca Iron 2006

The present study investigated the change of body composition in 8 ultra-endurance triathletes during a multi-stage ultra-endurance triathlon, where athletes had to perform one Ironman distance over 3.8 km swimming, 180 km cycling and 42.2 km running per day for 10 consecutive days. In the only 8 male successful finishers, body mass, skin fold thicknesses and circumferences of extremities were measured pre and post race in order to calculate skeletal muscle mass, percent body fat and fat mass. Bioelectrical impedance analysis was performed at the same time to determine lean body mass, percent body fat and total body water. Body mass did not change (p > 0.05), whereas skeletal muscle mass statistically significantly decreased by 1.1 kg (p < 0.05) and fat mass significantly decreased by 0.9 kg (p < 0.05).

No Effect of Pre Race Supplementation with Vitamins and Minerals on Performance in an Ultra-Endurance Race

Intake of supplements such as vitamins and minerals is widespread in athletes. The aim of the study was the investigation of the influence of intake of vitamins and minerals before an ultra-endurance triathlon and its effect on race performance in a descriptive field study. Participants of the “Triple Iron Triathlon Germany 2006“ in Lensahn, Schleswig-Holstein, Germany, were contacted by a newsletter six weeks before the race by the organizer and received a questionnaire to fill in their intake of vitamins and minerals. Questionnaires were self-administered and not administered by trained personnel. During this race the athletes had to cover 11.4 km swimming, 540 km cycling and 126.6 km running within 58 hours. The athletes were divided into two categories: successful finishers with intake of vitamins and minerals and successful finishers without intake prior to the race. Race performance (total running time in h) of athletes with intake and athletes without intake of these substances was compared. In the four-week period prior to the race, nine athletes (53 %) ingested vitamins and eight athletes (47 %) minerals. Athletes with intake of vitamins (44.7 ± 7.0 h versus 50.4 ± 4.4h; p>0.05) and minerals (45.3 ± 7.2 versus 49.3 ± 5.4 h, p>0.05) finished the race not faster than athletes without intake of vitamins and minerals. In the “Triple Iron Triathlon Germany 2006“ in Lensahn, Germany, no influence on race performance was observed concerning the regular intake of vitamins and minerals in the last four weeks before the race.