Ultra-endurance Athletes Research Articles

Effects of Sodium Intake on Health and Performance in Endurance and Ultra-Endurance Sports.

The majority of reviews on sports nutrition issues focus on macronutrients, often omitting or paying less attention to substances such as sodium. Through the literature, it is clear that there are no reviews that focus entirely on the effects of sodium and in particular on endurance sports. Sodium intake, both at high and low doses, has been found to be associated with health and performance issues in athletes. Besides, there have been theories that an electrolyte imbalance, specifically sodium, contributes to the development of muscle cramps (EAMC) and hyponatremia (EAH). For this reason, it is necessary to create this systematic review, in order to report extensively on the role of sodium consumption in the population and more specifically in endurance and ultra-endurance athletes, the relationship between the amount consumed and the occurrence of pathological disorders, the usefulness of simultaneous hydration and whether a disturbance of this substance leads to EAH and EAMC. As a method of data collection, this study focused on exploring literature from 1900–2021. The search was conducted through the research engines PubMed and Scopus. In order to reduce the health and performance effects in endurance athletes, simultaneous emphasis should be placed on both sodium and fluid intake.

Sleep Deprivation Training to Reduce the Negative Effects of Sleep Loss on Endurance Performance: A Single Case Study.

Sleep deprivation (SD) is very common during ultraendurance competitions. At present, stimulants such as caffeine and naps are the main strategies used to reduce the negative effects of SD on ultraendurance performance. In this case study, the authors describe the application of a novel strategy consisting of the intermittent repetition of SD (SD training [SDT]) during the weeks preceding an ultraendurance competition. A male ultraendurance runner underwent a 6-week SDT program (consisting of 1 night SD every Sunday) in addition to his regular physical training program before taking part in a 6-day race. Before and after SDT, the participant performed 5 consecutive days of daily 2-hour constant-pace running with SD on the first and third night. Psychological and physiological responses were measured during this multiday test. SDT was well tolerated by the athlete. A visual analysis of the data suggests that including SDT in the weeks preceding an ultraendurance competition may have beneficial effects on sleepiness and perceived mental effort in the context of 5 consecutive days of prolonged running and 2 nights of SD. This multiday test seems a feasible way for assessing ultraendurance athletes in the laboratory. The results provided some encouraging initial information about SDT that needs to be confirmed in a randomized controlled trial in a group of ultraendurance athletes. If confirmed to be effective and well tolerated, SDT might be used in the future to help ultraendurance athletes and other populations that have to perform in conditions of SD.

The evaluation of oral and dental health and behavioural risk among ultra-endurance athletes: a cross-sectional epidemiological study

ABSTRACT This study assessed for the first time the oral and dental health of ultra-trail athletes. We also confirmed and quantified the scale of their exposure to oral health risk factors. This was a cross-sectional study using data from a survey among runners who enlisted in the 2020 edition of the UT4M races (Ultra-Trail des 4 Massifs). The dental health of 84% of the participants was “good” or “very good”. The nutritional intake during effort comprised foods liable to induce tooth decay (energy bars (55%), sugar-rich gels and fruit confectionary (40%)) and snacking was frequent (39%). More than 3/5 of runners saw a dentist for preventive check-ups. The more runners participate in races the more likely they are to have oral hygiene strategies during competitions (aOR = 1.85, p ≤ 0.05). The oral health of ultra-trail runners is better than that of the average French adult population. Regular dental hygiene and preventive dental consultations appear to counterbalance the risks that we evidenced.

Influence of Female Sex Hormones on Ultra-Running Performance and Post-Race Recovery: Role of Testosterone.

In recent years, increasing numbers of women have participated in extremely long races. In adult males, there is a clear association between physiological levels of endogenous sex hormones and physical performance. However, the influence of plasmatic sex hormones and the effects of different types of hormonal contraception (HC) on the modulation of physical performance in adult females remain to be fully clarified. Eighteen female ultra-endurance athletes were recruited to participate in the study. Different variables were studied, including hematological parameters, body mass index, and body composition. Strength measurements were obtained using the squat-jump and hand-grip test. A repeated-measures analysis demonstrated significant differences in hematological values of CK and LDH pre-race as compared to immediately post-race and after 24/48 h. Furthermore, statistical differences were found in squat-jump and hand-grip test results after the ultramarathon. Testosterone, estradiol, and the testosterone/estrogen ratio were significantly correlated with muscle fatigue and were found to be indirect markers of muscle damage. A multivariate analysis demonstrated the protective role of testosterone against muscle damage and severe fatigue. Fluctuations in endogenous testosterone levels were correlated with greater fatigability and muscle damage after the competition. Adjusting the menstrual cycle with HC would not provide any further benefit to the athlete’s competitive capacity.

Predictors of Athlete's Performance in Ultra-Endurance Mountain Races.

Background: In previous studies, ultra-endurance performance has been associated with training and psychological variables. However, performance under extreme conditions is understudied, mainly due to difficulties in making field measures. Aim: The aim of this study was to analyze the role of training, hydration, nutrition, oral health status, and stress-related psychological factors in athletes’ performance in ultra-endurance mountain events. Methods: We analyzed the variables of race time and training, hydration state, nutrition, oral health status, and stress-related psychological factors in 448 ultra-endurance mountain race finishers divided into three groups according to race length (less than 45 km, 45–90 km, and greater than 90 km), using a questionnaire. Results: Higher performance in ultra-endurance mountain races was associated with better oral health status and higher accumulative altitude covered per week as well as higher positive accumulative change of altitude per week during training. In longer distance races, experience, a larger volume of training, and better hydration/nutrition prior to the competition were associated with better performance. Conclusions: Ultra-endurance mountain athletes competing in longer races (>90 km) have more experience and follow harder training schedules compared with athletes competing in shorter distances. In longer races, a larger fluid intake before the competition was the single best predictor of performance. For races between 45 and 90 km, training intensity and volume were key predictors of performance, and for races below 45 km, oral health status was a key predictor of performance. Psychological factors previously reported as ultra-endurance mountain race performance predictors were inconsistent or failed to predict the performance of athletes in the present research.

Pain sensitivity increases more in younger runners during an ultra-marathon.

Ultra-endurance research interest has increased in parallel with an increased worldwide participation in these extreme activities. Pain-related data for the growing population of ultra-endurance athletes, however, is insufficient. More data is especially needed regarding the variation in the aging populations of these athletes. We have previously shown that peripheral and central pain sensitivity increases during an ultra-marathon. To further clarify these changes inpain sensitivity during ultra-endurance competition we investigated these variations in two age populations: Younger runners≤39-year-old (younger) and an older group of runners being≥40years of age (older). Subjects were recruited from ultra-marathon competitions held over a three-year period in Florida, USA. All courses were flat with either hard macadam surface or soft sandy trails; run in hot, humid weather conditions. Pressure pain threshold (PPT) was measured with a pressure algometer on the distal, dominant arm before and immediately after an ultra-marathon. Conditioned pain modulation (CPM) was also measured pre and post, immediately after the PPT by placing the non-dominant hand in a cold-water bath maintained at 13.5±1.5°C. The difference between the pre and post measurements for both PPT and CPM were calculated and referred to as ΔPPT and ΔCPM, respectively for analysis. Data were analyzed with a Mixed 2×2 (Within X Between) MANOVA. Both PPT and CPM decreased during the ultra-marathons (p<0.05) in the younger group of runners. In the older runners there was not a statistically significant decrease in PPT during the ultramarathons whereas CPM did significantly decrease statistically (p=0.031). The ΔPPT was less in the older group compared to the younger group (p=0.018). The difference between the younger and older groups ΔCPM approached statistical significance at p=0.093. This statistical evidence suggests that the overall increase in peripheral and possibly central pain sensitivity was different between our age groups. Pain sensitivity during the ultra-marathon increased more in our younger group of runners than in our older group. This study suggests that there is an unidentified factor in an older population of ultra-marathon runners that results in an attenuated increase in pain sensitivity during an ultra-endurance activity. These factors may include a decreased innate immune response, lower fitness level, lower exertion during the ultra-marathon, variation in endorphin, enkephalin, endocannabinoid and psychological factors in the older age runners.

Energetics as a driver of human morphological thermal adaptation; evidence from female ultra-endurance athletes.

Functional benefits of the morphologies described by Bergmann's and Allen's rules in human males have recently been reported. However, the functional implications of ecogeographical patterning in females remain poorly understood. Here, we report the findings of preliminary work analysing the association between body shape and performance in female ultramarathon runners (n = 36) competing in hot and cold environments. The body shapes differed between finishers of hot and cold races, and also between hot race finishers and non-finishers. Variability in race performance across different settings supports the notion that human phenotype is adapted to different thermal environments as ecogeographical patterns have reported previously. This report provides support for the recent hypothesis that the heightened thermal strain associated with prolonged physical activity in hot/cold environments may have driven the emergence of thermally adaptive phenotypes in our evolutionary past. These results also tentatively suggest that the relationship between morphology and performance may be stronger in female vs. male athletes. This potential sex difference is discussed with reference to the evolved unique energetic context of human female reproduction. Further work, with a larger sample size, is required to investigate the observed potential sex differences in the strength of the relationship between phenotype and performance.

Sources of Nutrition Information in Recreational Ultra-marathon Runners: A Mixed Methods Analysis

Ultra-marathon events (i.e., .42.2-km) continue to grow in popularity; however, little is known regarding the sources of nutrition information which inform their beliefs and habits. The objective of this study was to characterize the acquisition of sport-specific nutrition information among ultra-endurance athletes using a mixed methods design. Qualitative data were collected through focus groups and analyzed using thematic analysis. Three primary higher order themes were identified: Optimal Diet for Ultra-Endurance Athletes, Common Sources of Information, and Barriers to Scientific Information. Then, a self-report inventory (Sources of Nutrition Information-SONI questionnaire) was developed to assess common sources of nutrition information and characterize their beliefs about those sources. Likert-type questions were used, and primary sources were scored out of 3, sub-questions out of 5. Differences between sources were assessed using RM-ANOVA. Participants (N = 224) accessed, responded to, and submitted the survey via a secure, study-specific web-based link. Peer reviewed literature was reported as the most frequently used (mean score = 1.64, p < 0.001), credible (3.02, p < 0.001), and interesting (2.62, p < 0.002). Social media was the most accessible (2.81, p < 0.001), but the least credible (1.87, p < 0.001). While social media was perceived less credible than other sources, its accessibility could make it a promising tool to provide evidence-based nutrition information to this population.

Comprehensive assessment of cardiovascular structure and function and disease risk in middle-aged ultra-endurance athletes

Background and aimsRecent studies suggest that long-term endurance training may be damaging to the heart, thus increasing cardiovascular disease (CVD) risk. However, studies utilizing cardiac imaging are conflicting and lack measures of central and peripheral vascular structure and function, which are also independently predictive of CVD events. MethodsWe performed a comprehensive assessment of cardiovascular structure and function in long-term (≥ 10 years) ultra-endurance athletes (ATH, 14 M/11 F, 50 ± 1 y) and physically active controls (CON, 9 M/9 F, 49 ± 2 y). ResultsAs expected, left ventricular mass and end-diastolic volume (echocardiography) were greater in ATH vs CON, whereas there was no difference in cardiac function at rest. Coronary artery calcium scores (computed tomography) were not statistically different between groups. There was no evidence of myocardial fibrosis (contrast magnetic resonance imaging) in any subject. Aortic stiffness (carotid-femoral pulse wave velocity) was lower in ATH vs CON (6.2 ± 0.2 vs 6.9 ± 0.2 m/s, p < 0.05), whereas carotid intima-media thickness (ultrasound) was not different between groups. Peripheral vascular endothelial function (flow-mediated vasodilation of the brachial artery) and microvascular function (peak blood velocity) in response to 5 min of forearm ischemia were not different between groups. Furthermore, there was no difference in 10-year coronary heart disease risk (ATH; 2.3 ± 0.5 vs CON; 1.6 ± 0.2%, p > 0.05). ConclusionsOur data indicate that middle-aged ultra-endurance ATH do not have marked signs of widespread cardiovascular dysfunction or elevated CHD risk compared to CON meeting physical activity guidelines.

Effects of 120 vs. 60 and 90 g/h Carbohydrate Intake during a Trail Marathon on Neuromuscular Function and High Intensity Run Capacity Recovery.

Background: Current carbohydrate (CHO) intake recommendations for ultra-trail activities lasting more than 2.5 h is 90 g/h. However, the benefits of ingesting 120 g/h during a mountain marathon in terms of post-exercise muscle damage have been recently demonstrated. Therefore, the aim of this study was to analyze and compare the effects of 120 g/h CHO intake with the recommendations (90 g/h) and the usual intake for ultra-endurance athletes (60 g/h) during a mountain marathon on internal exercise load, and post-exercise neuromuscular function and recovery of high intensity run capacity. Methods: Twenty-six elite trail-runners were randomly distributed into three groups: LOW (60 g/h), MED (90 g/h) and HIGH (120 g/h), according to CHO intake during a 4000-m cumulative slope mountain marathon. Runners were measured using the Abalakov Jump test, a maximum a half-squat test and an aerobic power-capacity test at baseline (T1) and 24 h after completing the race (T2). Results: Changes in Abalakov jump time (ABKJT), Abalakov jump height (ABKH), half-squat test 1 repetition maximum (HST1RM) between T1 and T2 showed significant differences by Wilcoxon signed rank test only in LOW and MED (p < 0.05), but not in the HIGH group (p > 0.05). Internal load was significantly lower in the HIGH group (p = 0.017) regarding LOW and MED by Mann Whitney u test. A significantly lower change during the study in ABKJT (p = 0.038), ABKH (p = 0.038) HST1RM (p = 0.041) and in terms of fatigue (p = 0.018) and lactate (p = 0.012) within the aerobic power-capacity test was presented in HIGH relative to LOW and MED. Conclusions: 120 g/h CHO intake during a mountain marathon might limit neuromuscular fatigue and improve recovery of high intensity run capacity 24 h after a physiologically challenging event when compared to 90 g/h and 60 g/h.

Total Dietary Antioxidant Intake Including Polyphenol Content: Is it Capable to Fight against Increased Oxidants within the Body of Ultra-Endurance Athletes?

The role of dietary antioxidants on exhaustive exercise-induced oxidative stress has been well investigated. However, the contribution of total dietary antioxidant capacity on exogenous antioxidant defense and exercise performance has commonly been disregarded. The aims of the present investigation were to examine (i) the effects of dietary total antioxidant intake on body antioxidant mechanisms, and (ii) an exhaustive exercise-induced oxidative damage in ultra-endurance athletes. The study included 24 ultra-marathon runners and long-distance triathletes (12 male and 12 female) who underwent an acute exhaustive exercise test (a cycle ergometer (45 min at 65% VO2max) immediately followed by a treadmill test (75% VO2max to exhaustion). Oxidative stress-related biomarkers (8-isoprostaglandin F2alpha (8-iso PGF2a), total oxidant status (TOS, total antioxidant status (TAS)) in plasma were collected before and after exercise. Oxidative stress index was calculated to assess the aspect of redox balance. Blood lactate concentrations and heart rate were measured at the 3rd and 6th min after exercise. Dietary antioxidant intake was calculated using the ferric reducing ability of plasma (FRAP) assay. Dietary total antioxidant intake of the subjects was negatively correlated with pre-exercise TOS concentrations (rs = −0.641 in male, and rs = −0.741 in females) and post- vs. pre- (∆) 8-iso PGF2a levels (rs = −0.702 in male; p = 0.016, and rs = −0.682 in females; p = 0.024), and positively correlated with ∆ TAS concentrations (rs = 0.893 in males; p = 0.001, and rs = 0.769 in females; p = 0.002) and post- exercise lactate concentrations (rs = 0.795 for males; p = 0.006, and rs = 0.642 for females; p = 0.024). A positive meaningful (p = 0.013) interaction was observed between time at exhaustion and dietary antioxidant intake (rs = 0.692) in males, but not in females. In conclusion, the determination of total dietary antioxidant intake in ultra-endurance athletes may be crucial for gaining a better perspective on body antioxidant defense against exhaustive exercise-induced oxidative stress. However, the effects of dietary antioxidant on exercise performance and recovery rate needs further investigation.

Structural brain differences between ultra-endurance athletes and sedentary persons

Participation in ultra-endurance events has increased in recent years and requires extreme levels of moderate to vigorous physical activity (MVPA). Moderate levels of MVPA have been associated with increased brain volume but the effects of extreme levels of MVPA on brain volume is unknown. As a result, we sought to compare the brains of those who engage in extremely high levels of MVPA with those who are sedentary using magnetic resonance imaging. We performed whole brain volumetric analyses and voxel-based morphometry on 12 ultra-endurance athletes (1078.75 ± 407.86 min of MVPA/week) and 9 sedentary persons (18.0 ± 56.9 min of MVPA/week). Whole-brain analyses revealed that those who participate in ultra-endurance training have increased grey (p< 0.0001), white (p = 0.031), and total matter volume (p < 0.0001), while regional analyses revealed that ultra-endurance athletes have smaller regional grey matter volume in the right primary sensory and motor cortex, inferior and middle frontal gyrus, and left thalamus. Future research is warranted to determine why ultra-endurance athletes have lower regional volumes in these areas despite having overall increased grey and white matter volumes.

Multidisciplinary Analysis of Differences Between Finisher and Non-finisher Ultra-Endurance Mountain Athletes.

Ultra-endurance races are one of the most physically and psychologically demanding sports, depending performance on several elements. The aims of the present study were (i) to analyze differences in selected psychophysiological parameters between finisher and non-finisher ultra-endurance mountain athletes, and (ii) to analyze modifications in psychophysiological parameters before and after an ultra-endurance mountain event. Selected psychophysiological variables were assessed in 46 finishers and 24 non-finishers in two over 100 km ultra-endurance races were examined. We found how an ultra-endurance mountain race produced dehydration, a decrease in systolic blood pressure, weight and leg strength muscle values, as well as an increase in heart rate and rate of perceived exertion values. Finishers presented lower systolic blood pressure, weight, body mass index, half marathon time and fluid intake before competition day compared to non-finishers. In addition, body mass index, pre-race hydration, and performance in lower distance races were predictors of performance in these ultra-endurance mountain races.

Sources Of Nutrition Information And Knowledge For Ultra-runners

PURPOSE: Ultra-marathon events (i.e., >42.2-km) continue to grow in popularity; however, little research exists on the typical dietary intake of ultramarathon participants, or the sources of information which influence their habits and beliefs. The objectives of this study were to characterize the acquisition of nutrition information among ultra-endurance athletes, and to determine the relationship between the use of different sources of information and nutritional knowledge (relative to current evidence-based recommendations). METHODS: Participants (n=196) were adults who had completed an ultramarathon at least once in the past 2 years. Measures included: a demographic questionnaire; the Sources of Nutrition Information (SONI) questionnaire, which included 7 major sources of nutrition information, as well as their credibility, accessibility, frequency, interest; and the General Nutrition Knowledge Questionnaire -Revised (GNKQ-R). Repeated measures ANOVA was used to analyze differences between items on the SONI scale. Spearman rank correlation was used to test for a relationship between sources of information and GNKQ-R score. RESULTS: 18% self-identified as vegan/vegetarian, 6% paleo/ketogenic, 20% traditional American diet, 54% “healthy” and 12% “other”. Peer reviewed literature was reported as the most frequently used (mean score=1.64, p<0.001), credible (3.02, p<0.001), and interesting (2.62, p=0.002). Social media was the most accessible (2.81, p<0.001), but the least credible (1.87, p<0.001). A modest, significant correlation (r=0.185, p = 0.015) exists between use of peer-reviewed literature and nutrition knowledge. CONLCUSIONS: Ultrarunners report high usage of peer-reviewed literature for nutrition information, which is related with improved nutritional knowledge. Because of its accessibility, social media may be a promising tool to provide nutrition information to this population.

Cardiovascular Disease Risk In Middle-Aged Ultra-Endurance Athletes

It is widely accepted that aerobic exercise reduces cardiovascular disease (CVD) risk. However, recent studies suggest that volumes of exercise that greatly exceed physical activity guidelines may be damaging to the heart. Currently, it is unclear if individuals who train for ultra-endurance races have an elevated risk of developing CVD compared to those that perform lower amounts of physical activity. Additionally, little work has been done to examine vascular function in these athletes. PURPOSE: To evaluate cardiovascular function and calculate CVD risk to determine if individuals that train for ultra-endurance races have a greater risk compared to individuals that engage in moderate physical activity. METHODS: We examined cardiovascular function in athletes (ATH, 14M/11F, 50±1 y) that had been training for ultra-endurance events for 10+ years and controls (CON, 9M/9F, 49±2 y) that were meeting current ACSM physical activity guidelines. We used cardiac computed tomography (CT) to calculate coronary artery calcium scores (CACS) and contrast-enhanced magnetic resonance imaging (MRI) to identify myocardial fibrosis (MF). Carotid-femoral pulse wave velocity (cfPWV) was used to evaluate aortic stiffness and ultrasound assessment of carotid intima-media thickness (CIMT) was used to determine vascular structure of the carotid artery. Additionally, we used Doppler ultrasound to assess vascular endothelial function by measuring flow-mediated dilation (FMD) of the brachial artery. Finally, we used a risk score calculator to determine 10-year CVD risk. RESULTS: CACS > 0 was observed in 8 ATH and 2 CON; however, the presence of CAC was not significantly different between groups (P>0.05). Additionally, no participant in ATH or CON had MF. ATH had lower cfPWV compared to CON (6.2±0.2 vs 6.9±0.2 m/s, P<0.05), while no difference in CIMT (ATH; 0.64±0.02 vs CON; 0.62±0.03 mm, P>0.05) or FMD (ATH; 3.6±0.8 vs CON; 5.6±1.2 %, P>0.05) was observed. Furthermore, there was no group difference in calculated CVD risk (ATH; 2.4 ± 0.6 vs CON; 1.6 ± 0.3 %, P>0.05). CONCLUSION: Middle-aged ATH with 10+ years of training for ultra-endurance races are not at a greater risk of developing CVD than individuals that are meeting current physical activity guidelines.

Common and Uncommon Injuries in Ultra-endurance Sports

Ultra-endurance sports are associated with prolonged physical exercise both during training and competition. Musculoskeletal injuries are common as a result of the repetitive physical stresses. Stress fractures in the weight-bearing bones should always be suspected when ultra-endurance athletes present with pain over bony structures. Most stress fractures can be treated with activity modifications but some such as femoral neck and tibial shaft stress fractures may require operative fixation. The knee seems to be the most frequent source of injuries in ultra-endurance athletes. Patellofemoral symptoms from tendon injuries or chondral problems are common injuries and can be challenging to treat. Lower leg, ankle, and foot injuries also make up a significant portion of the ultra-endurance injuries. Peritendinitis of the extensor tendons at the extensor retinaculum of the anterior ankle or "ultramarathoner's ankle" seems to be a unique injury associated with ultramarathons. Other lower leg injuries include medial tibial stress syndrome (MTSS) and chronic exercise-induced compartment syndrome (CECS).

Depression in Ultra-endurance Athletes, A Review and Recommendations.

Depression affects 6.7% of the adult population each year and studies indicate the annual prevalence is similar or even higher in athletes. It is often insidious and not recognized. There continues to be stigma and misunderstanding about the disorder that is a barrier to getting an accurate diagnosis and effective treatment. It is important for people living with depression to get professional help because the condition itself can be disabling, increases risk of suicide, and reduces quality of life. There is some evidence that depression and suicide risk is higher in endurance athletes such as track and field, marathoner, and ultramarathoners. There have been studies of athletes looking at rates reporting depressive symptoms and on factors in suicide attempts in the athletes. Studies have reviewed risk factors unique to athletes for depression. This article will review depression in the endurance athlete and approaches in treatment in that population.

Proper Hydration During Ultra-endurance Activities.

The health and performance of ultra-endurance athletes is dependent on avoidance of performance limiting hypohydration while also avoiding the potentially fatal consequences of exercise-associated hyponatremia due to overhydration. In this work, key factors related to maintaining proper hydration during ultra-endurance activities are discussed. In general, proper hydration need not be complicated and has been well demonstrated to be achieved by simply drinking to thirst and consuming a typical race diet during ultra-endurance events without need for supplemental sodium. As body mass is lost from oxidation of stored fuel, and water supporting the intravascular volume is generated from endogenous fuel oxidation and released with glycogen oxidation, the commonly promoted hydration guidelines of avoiding body mass losses of >2% can result in overhydration during ultra-endurance activities. Thus, some body mass loss should occur during prolonged exercise, and appropriate hydration can be maintained by drinking to the dictates of thirst.

Evidence of the Exercise-Hypogonadal Male Condition at the 2011 Kona Ironman World Championships.

Prior research has illustrated that high volumes of aerobic exercise result in a reduction in basal concentrations of testosterone in men. Those studies were mostly conducted on recreational runners and identified reduced testosterone, but not concentrations low enough to be considered pathological. Therefore, the purpose of this study was to assess the basal concentrations of testosterone and cortisol in elite triathletes, as well as the impact of a World Championship race, on the acute responses of these hormones. A total of 22 men (age 40.6 [11.5]y, height 179 [6]cm, weight 77.0 [7.0]kg) who participated in the 2011 Ironman World Championships served as subjects. Resting blood samples were taken 2-4 d prior to provide a baseline (BL), as well as immediately, 1 d, and 2 d after the event and were later analyzed for total testosterone and cortisol concentrations. At BL, 9 men had a normal testosterone concentration, whereas 9 men fell within a "gray zone" and 4 other men demonstrated concentrations suggestive of deficiency. Testosterone was significantly lower than BL at 1 d (95% confidence interval [CI] 0.10-0.34, P < .001, ES = 0.53) and 2 d (95% CI 0.01-0.21, P = .034, ES = 0.35) after the event. Cortisol was significantly different from BL at immediate post (95% CI 1.07-0.83, P < .001, ES = 8.0). There were significant correlations between time and age (R = .68, P = .001), as well as BL testosterone and cortisol (R = .51, P = .015). Elite ultraendurance athletes may demonstrate not only reduced testosterone but also sometimes clinically low concentrations that could be indicative of androgen deficiency.

Effects of hour of training and exercise intensity on nocturnal autonomic modulation and sleep quality of amateur ultra-endurance runners

Sleeping problems can affect physiological adaptations and the recovery process. The aim of this study was to analyse the effect of the intensity and the hour of the training session on sleep quality and cardiac autonomic activity in amateur ultra-endurance athletes. We used a comparative, randomized crossover design to test the effect of moderate (M) or vigorous (V) intensity and morning (m) or evening (e) training journey, separated by 72 h of recovery, on actigraphic and subjective sleep quality and nocturnal cardiac autonomic activity in fourteen ultra-endurance male runners. No significant differences among training sessions were found in nocturnal heart rate variability or in subjective sleep quality, but participants experienced significantly higher calm sleep after Mm than Me (p = 0.028; ES = 0.7) and more refreshed after awakening when they performed a Me than Vm (p = 0.04; ES = 0.6). Higher sleep efficiency was found when the training is performed in the morning compared to the evening sessions in both intensities, and it was also observed in Me vs Ve (p = 0.012; ES = 0.8). Significantly lower numbers of awakenings were observed when the training was performed in the morning, and actual sleep time was significantly lower when participants performed a vigorous training session compared to a moderate one (Vm vs Mm: p = 0.035; ES = 0.6; Ve vs Mm: p = 0.036; ES = 0.6). Moderate exercise performed in the morning had a higher sleep efficiency compared to other types of training and intensity training is more important than the time of the day of training on sleep quality.