Endurance Race Research Articles

Post-race reactions: The emotional paradox of high performance and anxiety – a conventional content analysis

BackgroundStudies examining post-race emotional experiences in the context of endurance races among recreational athletes are scarce. The purpose of this study was to describe how recreational athletes experience the time after completing an endurance race.MethodsIn this study, a qualitative study design was used, and data collection was carried out with semi-structured interviews. The selection of subjects was completed systematically through criterion selection. The selection criteria were men and women, aged 18 years or older, who had completed an endurance race, and finished, lasting at least 180 min within the past 12 months. The interviews were analyzed using conventional qualitative content analysis.ResultsSixteen recreational endurance athletes who, within six months, had completed an endurance race of running, cycling, cross-country skiing or Ironman, participated and were interviewed. Four overarching themes emerged from the analysis: “High on life”, “Loss of energy, Ambivalence and Melancholy”, “Activity-charged emotions”, and “Dimensions of emotions over time and new goals”, describing the content of the interviews.ConclusionsEndurance athletes experienced varied post-race emotions that were both physically and mentally challenging, suggesting a holistic approach to managing post-race emotions would be beneficial. From the athletes’ perspectives, post-race feelings were dependent on many factors, including time spent training for a specific race, and perceived inability to set new goals for an upcoming training period. Setting future goals prior to an event may be a tool for reducing the risk of negative post-race emotions, including post-race blues.

Sleep deprivation and recovery: Endurance racing as a novel model.

The aim of this study was to investigate sleep-wake behavior and gain insights into perceived impairment (sleep, fatigue, and cognitive function) of athletes competing in two international multi-day adventure races. Twenty-four athletes took part across two independent adventure races: Queensland, Australia and Alaska, USA. Individual sleep periods were determined via actigraphy, and racers self-reported their perceived sleep disturbances, sleep impairment, fatigue and cognitive function. Each of these indices was calculated for pre-, during- and post-race periods. Sleep was severely restricted during the race period compared to pre-race (Queensland, 7:46 [0:29] vs. 2:50 [1:01]; Alaska, 7:39 [0:58] vs. 2:45 [2:05]; mean [SD], hh:mm). As a result, there was a large cumulative sleep debt at race completion, which was not 'reversed' in the post-race period (up to 1week). The deterioration in all four self-reported scales of perceived impairment during the race period was largely restored in the post-race period. This is the first study to document objective sleep-wake behaviors and subjective impairment of adventure racers, in the context of two geographically diverse, multi-day, international adventure races. Measures of sleep deprivation indicate that sleep debt was extreme and did not recover to pre-race levels within 1week following each race. Despite this objective debt continuing, perceived impairment returned to pre-race levels quickly post-race. Therefore, further examination of actual and perceived sleep recovery is warranted. Adventure racing presents a unique scenario to examine sleep, performance and recovery.

Immunology of Physical Exercise: Is Equus caballus an Appropriate Animal Model for Human Athletes?

Domestic horses routinely participate in vigorous and various athletic activities. This enables the horse to serve as a model for studying athletic physiology and immunology in other species, including humans. For instance, as a model of physical efforts, such as endurance rides (long-distance running/aerobic exercise) and races (anaerobic exercise), the horse can be useful in evaluating post-exercise response. Currently, there has been significant interest in finding biomarkers, which characterize the advancement of training and adaptation to physical exercise in the horse. The parallels in cellular responses to physical exercises, such as changes in receptor expression and blood cell activity, improve our understanding of the mechanisms involved in the body's response to intense physical activity. This study focuses on the changes in levels of the pro- and anti-inflammatory cytokines and cellular response in the context of post-exercise immune response. Both the direction of changes in cytokine levels and cellular responses of the body, such as proliferation and expression of surface markers on lymphocytes, monocytes and neutrophils, show cross-functional similarities. This review reveals that horses are robust research models for studying the immune response to physical exercise in human athletes.

Avaliação de componentes do metabolismo lipídico basal e adiposidade de cavalos Árabes treinados para corrida e para Enduro

ABSTRACT: Endurance and flat race are entirely different efforts and thus require completely different organism adaptations to achieve the performance. This study aimed to examine the difference in basal lipid metabolism in Arabian horses undergoing different training regimens for endurance and race and possible gender differences. The study enrolled sixty male and female’ Arabian horses; thirty were trained for race, and thirty were trained for 80 km endurance races. The analyses included body condition score, body weight, body mass index, % body fat, and blood collected to determine triglycerides, total cholesterol, low-density proteins, high-density proteins, and non-esterified fatty acids. Ultrasonography was used to measure the thickness of the subcutaneous fat layer in the longissimus dorsi muscle, as well as the thickness of the rump fat and the cross-section of the gluteus medius muscle. This study showed that lipid profile is more influenced by type of exercise than by gender, being more efficient on endurance horses.

Model Predictive Control Strategies for Electric Endurance Race Cars Accounting for Competitors’ Interactions

Model Predictive Control Strategies for Electric Endurance Race Cars Accounting for Competitors’ Interactions

Biomechanical changes identified during a marathon race among high-school aged runners

BackgroundDespite the increasing popularity of endurance running competitions among adolescent runners, there is currently limited information regarding expected biomechanical changes across the duration of a long-distance running event, and the relationship between young runners’ biomechanics and running performance. Wearable technology offers an ecological means to continuously assess runners’ biomechanical data during outdoor running competitions. Research questionDo adolescent athletes adopt changes in sensor-derived biomechanics throughout a marathon race, and are there relationships between race performance and biomechanical features among young marathoners? MethodsFourteen high-school aged runners (9 M, 5 F; age: 16 ± 1 years, height: 170.8 ± 7.5 cm; mass: 63.6 ± 9.4 kg) wore lace-mounted sensors to record step-by-step biomechanics during a marathon race. Official race segment completion times were extracted across 5 race segments (5-K, 15-K, Half Marathon [21.1-K], 35-K, Marathon [42.2-K]). Within-participant repeated measures of covariance (pace) were conducted to assess changes in biomechanics across the race, with Bonferroni post-hoc comparisons. Pearson’s r correlations were performed to assess the relationship between race finish times and biomechanics. ResultsPace was significantly slower (p-range: 0.002–0.005), contact times significantly longer, and stride lengths significantly shorter in the final segment compared to middle segments (p-range: 0.003–0.004). The rate of shock accumulation was significantly higher in the final race segment compared to the first three segments (p-range: 0.001–0.002). Moderate relationships existed between finish times and pace (r = −0.63), stride length (r = −0.62), and contact time (r = 0.51). SignificanceAdolescent runners altered their gait patterns in the final marathon segment compared to earlier segments. Spatiotemporal measures were moderately correlated with race finish times, suggesting a link between faster run pace, increased stride lengths, and reduced contact time for improved running performance during an endurance race.

Le registre RACE Paris

The Register of Cardiac Accidents of Endurance Races in Paris (RACE Paris), an observational prospective cohort study collected sudden deaths and life-threatening accidents from five major Parisian endurance races over 10 years.

Endurance Track: A Comprehensive Embedded System for Equestrian Endurance Race Management

Endurance Track: A Comprehensive Embedded System for Equestrian Endurance Race Management

Identification of Differentially Expressed Genes after Endurance Runs in Karbadian Horses to Determine Candidates for Stress Indicators and Performance Capability.

RNA sequencing makes it possible to uncover genetic mechanisms that underlie certain performance traits. In order to gain a deeper insight into the genetic background and biological processes involved in endurance performance in horses, the changes in the gene expression profiles induced by endurance runs over long (70 km) and short (15 km) distances in the blood of Kabardian horses (Equus caballus) were analyzed. For the long-distance runs, we identified 1484 up- and 691 downregulated genes, while after short-distance runs, only 13 up- and 8 downregulated genes (FC > |1.5|; p < 0.05) were found. These differentially expressed genes (DEGs) are involved in processes and pathways that are primarily related to stress response (interleukin production, activation of inflammatory system) but also to metabolism (carbohydrate catabolic process, lipid biosynthesis, NADP metabolic process). The most important genes involved in these processes therefore represent good candidates for the monitoring and evaluation of the performance of horses in order to avoid excessive demands when endurance performance is required, like ACOD1, CCL5, CD40LG, FOS, IL1R2, IL20RA, and IL22RA2, on the one hand, and, on the other hand, for assessing the suitability of a horse for endurance races, like GATA2, GYG1, HIF1A, MOGAT1, PFKFB3, PLIN5, SIK1, and STBD1.

Molecular insights into the lipid-carbohydrates metabolism switch under the endurance effort in Arabian horses.

Recent studies have shown that in Arabian horse muscle, long-term exercise-induced expression of genes related to fatty acid degradation and the downregulation of genes belonging to the glycolysis/gluconeogenesis and insulin signalling pathways. Long-lasting physical exertion may trigger the metabolism to switch the main energy source from carbohydrates to lipids due to higher caloric content. To describe the metabolism adaptation at the whole transcriptome of blood to endurance effort in Arabian horses. In vivo experiment. Venous blood samples from 10 Arabian horses were taken before and after a 120 km long endurance ride to isolate the RNA and perform the high-throughput NGS transcriptome sequencing. The results, including KEGG (Kyoto Encyclopaedia of Genes and Genomes) and GO (Gene Ontology) analyses, allowed us to describe the most significantly upregulated-ARV1, DGAT2, LIPE, APOA2, MOGAT1, MOGAT2, GYS1, GYS2 and downregulated-ACACA, ACACB, FADS1, FADS2 genes involved in carbohydrate and lipid metabolism. Also, the increased expression of RAF1, KRAS and NRAS genes involved in the Insulin pathway and PI3K-Akt was shown. Limited sample size, Arabians used for endurance racing were not compared to Arabians from other equestrian disciplines. This general insight into the processes described supports the thesis of the lipid-carbohydrates metabolism switch in endurance Arabian horses and provides the basis for further research.

Assessment of gastrointestinal health in racing Alaskan sled dogs using capsule endoscopy and inflammatory cytokines.

Exercise-induced gastrointestinal syndrome occurs in dogs and people and might compromise athlete performance by increasing intestinal permeability and causing gastrointestinal erosions. Racing sled dogs often receive acid suppressant prophylaxis which decreases the incidence of gastric erosions induced by exercise. The objectives were to quantify intestinal injury by measuring serum pro-inflammatory cytokine concentrations before and after exercise and to evaluate gastrointestinal mucosa using video capsule endoscopy after exercise. Prospective study of 12 racing Alaskan sled dogs receiving approximately 1 mg/kg omeprazole once daily from the day before the race until race completion. Blood was drawn before and 8 to 10 hours after an endurance race for the quantification of cytokines. Gastrointestinal tract mucosa was assessed with video capsule endoscopy immediately post-race. Eight of nine dogs (89%; 95% confidence interval 52 to 100%) had gastric erosions; all dogs (100%, 95% confidence interval 63 to 100%) had small intestinal erosions. Most of the dogs (seven of nine) had straw or foreign material present. Cytokine levels were not different from before to after the race. Video capsule endoscopy identified gastrointestinal tract mucosal erosions after exercise in all dogs receiving once-daily omeprazole treatment, though other causes for the lesions besides exercise are possible.

Risk Assessment of Heat Stroke during the Marathon of the Tokyo 2020 Olympics in Sapporo, Hokkaido

A marathon is a grueling endurance race, and runners are at risk of heatstroke. Therefore, the thermal environment of the marathon course should be accurately assessed. Solar radiation, a factor in the thermal environment, is particularly affected by the surrounding environment. In this study, we proposed a method to calculate wet-bulb globe temperature (WBGT) in a short period of time using geographic information system (GIS) data, considering changes in solar radiation. WBGT is used as an indicator of heat stroke. This method was used to assess the risk of heat stroke due to weather conditions, span of time, and location on the marathon course of the Tokyo 2020 Olympics. According to the analysis results, in Sapporo, trees and buildings can suppress WBGT by about 2 °C, but on days when the average temperature exceeded 26 °C, WBGT exceeded 21 °C from 5:00 to 13:00. On the contrary, even in August, the hottest month of the year, there were days when WBGT was almost always below 21 °C from 5:00 to 13:00. In other words, it is concluded that the risk of heat stroke can be reduced if the marathon is held in accordance with the weather conditions of the day. In addition, by mapping and identifying locations where there is little change in attenuated WBGT, it is possible to identify locations where the thermal environment should be improved.

Hydroelectrolytic and Acid-Base Parameters after 80 to 115 km Endurance Races (Raid Uruguayo) and Their Association with the Comfort Index.

The Raid Uruguayo (RAID) is an equestrian endurance competition. This study characterized the hydroelectrolytic parameters (Na+, K+, Cl-, tCa++, and iCa++), hematocrit (Ht), total plasma protein (TPP), and blood pH from 900 equine athletes (finishers and non-finishers) competing over distances of 80 to 115 km under different climate conditions. Paired blood samples were taken prior to the start of the competition (sample 1) and at the end of the race or at the time of leaving the competition (sample 2). The association of the comfort index (CI: low, moderate, and high) with blood parameters was evaluated. Of the 900 horses included, 550 were not able to finish the trial. The comfort index was not associated with success in completing the race. In the horses that finished the race, the CI was not associated with Ht, pH, TPP, or Na+ concentrations in samples taken after finishing the RAID. In contrast, the decreases in chloride, K+, tCa++, and iCa++ concentrations found after the race were more pronounced at moderate and high CI values when compared with low CI values. In horses that did not finish the race, the CI was associated with all variables except for Ht. The data confirmed the relevance of considering the impact of the comfort index in hydroelectrolytic losses in the RAID, as it influence ssuccess or failure in the performance of endurance horses finishing the competition.

Pre- and post -exercise variation of blood parameters on performance endurance horses: a first race study from Algeria

Abstract: This paper presents the first study conducted in Algeria to determine the pre and post-race hematological and biochemical parameters of horses of a 90 km endurance race for eliminated horses’ category and those who completed the races with good performance. This study was conducted on 15 endurance horses (10 Arabian Thoroughbred, 4 Arabian-Barb and 1 Barb). Nine (9) horses successfully completed the endurance race, whereas the other 6 were eliminated. Blood samples were collected from each animal before and after the end of the race. Whole blood samples were used for measuring the blood-biochemical parameters. Our results showed a significant increase in the hematological parameters (RBC, HB, Ht and MCV), the total leucocyte count, neutrophils and platelets for the group of horses who finished the race successfully. A significant decrease was noticed for the lymphocytes and eosinophils numbers while serum biochemical parameters showed a significant increase of Ca, TG, urea, U-A, AST and CK and a decrease of Mg, CHE, GLU and ƔGT. This study showed that, for the eliminated horses, there were significant changes in values of the total leucocytic count, lymphocytes, neutrophils, HB and Ht as compared to good performance horses. Serum biochemical parameters showed a significant increase of TG, U-A, AST and CK and a significant decrease of Ca, Mg, CHE and ƔGT. Most of the hemato-biochemical parameters of both the eliminated horses and those who completed the race successfully depicted significant differences. The results of this study suggested that biochemical findings could help identify horses with an increased risk of developing metabolic alterations before their elimination during competitive endurance races of different distances. Therefore, proper management protocols, standard feeding and watering with proper preparation of animals before the race could prevent electrolytes imbalance and pathological affections during racing.

The effects of a 3-day mountain bike cycling race on the autonomic nervous system (ANS) and heart rate variability in amateur cyclists: a prospective quantitative research design

BackgroundThe acute and chronic adaptation of endurance athletes’ hearts shows that increased volume of endurance exercise might cause an acute reduction in cardiac function, causing a physiological cascade that leads to the release of cardiac biomarkers specific to cardiomyocyte stress. Heart rate variability (HRV) is a valuable tool used as a physiological measurement to evaluate the autonomic nervous system (ANS). It is frequently used to assess cardiac autonomic regulation, determining a patient’s risk for unfavorable events. This study set out to determine the changes in the ANS by participating in a 3-day mountain bike cycling race in amateur cyclists using HRV as an outcome measure.MethodsSixteen healthy participants (male and female) participating in a 3-day mountain bike cycling race underwent five-minute resting electrocardiography recordings in a supine position 2 days before the race (baseline testing). In addition, HRV measurements were recorded after each race day and 24 h post-race (recovery).ResultsTime-domain and frequency-domain measures showed significant changes from baseline HRV parameters after each race day (p ≤ 0.05). In addition, our data revealed that the mean heart rate and R–R variability intervals did not return to baseline values after 24 h of recovery. Thus, autonomic nervous system (ANS) alterations may be due to changes in cardiac sympatho-vagal balance.ConclusionsThe main strength of this study is using HRV as a measuring and screening tool to assess cardiac autonomic activity, whereby the state of the ANS before and after endurance races can be measured. Thus, physicians, athletes, and coaches can determine the stress of endurance races on the ANS and plan recovery strategies. The reasoning is that if the ANS is in a state of sub-optimal function, susceptible amateur athletes might be at risk for a cardiovascular event or maladaptation due to the endurance race.

People express more bias in their predictions than in their likelihood judgments.

The desirability bias refers to when people's expectations about an uncertain event are biased by outcome preferences. Prior work has provided limited evidence that the magnitude of this motivated bias depends on (is moderated by) how expectations are solicited-as discrete outcome predictions or as likelihood judgments expressed on more continuous scales. The present studies extended the generalizability and understanding of the moderating process. The authors proposed that solicitations of predictions and likelihood judgments have different connotations that ultimately affect how much bias is expressed; this varies from a prior account that attributed the moderation effect to response scale differences (dichotomous vs. continuous). Study 1 confirmed the connotation difference, with predictions being viewed as more affording of hunches. Studies 2-4 directly tested the moderation effect, and unlike prior work focusing on expectations for purely stochastic events, the present studies involved more naturalistic events for which likelihood information was not supplied or directly knowable. Before viewing scenes from a basketball game (Study 2) or an endurance race (Studies 3 and 4), participants were led to prefer one contestant over another. After viewing most of the closely fought contest, they made either a prediction or likelihood judgment about the outcome. Participants' tendency to forecast their preferred contestant to win was significantly stronger among those making predictions rather than likelihood judgments. In support of the proposed account, this effect persisted even when both types of solicitations offered only dichotomous response options. Broader implications for measuring and understanding people's expectations or forecasts are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Prevalence of radiographic changes in forelimb digits and metacarpophalangeal joints of South African endurance racehorses.

If the number of events alone is considered, endurance riding is the fastest growing and the second-most popular Fédération Equestre Internationale (FEI) discipline. Lameness is the most common cause of elimination from endurance races worldwide. To the authors' knowledge, no studies have been published investigating the prevalence of radiographic changes in the forelimb digits and metacarpophalangeal joints (MCP) of endurance racehorses in South Africa. Investigate the prevalence of radiographic changes in the forelimb digits and MCP joints of South African endurance racehorses. One hundred endurance racehorses registered with ERASA were volunteered by their owners to partake in the current study. Radiographs were obtained from horses competing in endurance races during the 2018-2019 endurance racing season. Radiographs included seven standard views of each distal forelimb. Radiographic images were independently evaluated by three observers, point prevalence and inter-rater reliability (IRR) was calculated. Data analysis of the forelimb digits revealed a large proportion of horses with bilateral signs of dorsopalmar hoof imbalance (95%); a diversion from a straight digital axis (91%), with an extended (broken back) proximal interphalangeal joint (67%) being the most common abnormality. Osteoarthritis of the proximal (16%) and distal (7%) interphalangeal joints was only observed in a low percentage of horses. Interestingly, the hoof-distal-phalanx-ratio of the majority (86%) of horses was more than 25% but none of these horses showed any other signs of chronic laminitis, indicating that hoof-distal-phalanx-ratio might not be a reliable indicator of chronic laminitis in this population of horses. Ossification of the ungular cartilages was observed in the majority (69%) of horses, either affecting one or both distal phalanges. Descriptive data analysis of the MCP joints showed that a large proportion of horses displayed radiological signs of MCP joint osteoarthritis (28%), with 10% being bilateral. The current study provides insight into radiographic changes and their prevalence in the distal front limbs of South African endurance racehorses. Knowledge about the prevalence of specific radiographic changes would enable equine practitioners to better evaluate and manage horses that are affected. Although no correlations were made with age, speed or number of competitive kilometres competed, the current study may serve as a basis for future research.

Changes in Acute Phase Response Biomarkers in Racing Endurance Horses.

This study aimed to evaluate if exercise-induced acute phase response (APR) occurs in endurance horses in response to the race. The study included 23 horses competing in an endurance competition with a successfully passed clinical examination before the race. Blood samples were collected before the start and within 30 min after the end of the race. Haematological and biochemical tests were performed and correlated to acute phase biomarkers changes. Values of calprotectin and haptoglobin (Hp) decreased after the races compared to values before, while concentrations of ceruloplasmin and albumin recorded a significant increase. Greater changes in calprotectin values were noted in Arabian horses compared to other breeds. Values of Hp showed a significantly greater decrease after longer races. Based on study results, endurance racing induces APR in horses characterised by significant changes in selected acute phase biomarkers. More pronounced changes were noted at races with higher average speeds, suggesting the need for thorough horse monitoring during exhausting races.

Maximum-distance race strategies for a fully electric endurance race car

This paper presents a bi-level optimization framework to compute the maximum-distance stint and charging strategies for a fully electric endurance race car. Thereby, the lower level computes the minimum-stint-time Powertrain Operation (PO) for a given battery energy budget and stint length, whilst the upper level leverages that information to jointly optimize the stint length, charge time and number of pit stops, in order to maximize the driven distance in the course of a fixed-time endurance race. Specifically, we first extend a convex lap time optimization framework to capture multiple laps and force-based electric motor models, and use it to create a map linking the charge time and stint length to the achievable stint time. Second, we leverage the map to frame the maximum-race-distance problem as a mixed-integer second order conic program that can be efficiently solved to the global optimum with off-the-shelf optimization algorithms. Finally, we showcase our framework on a 6 h race around the Zandvoort circuit. Our results show that a flat-out strategy can be extremely detrimental, and that, compared to when the stints are optimized for a fixed number of pit stops, jointly optimizing the stints and number of pit stops can increase the driven distance of several laps.

Dietary and Biochemical Profile of Congolese Athletes in Endurance Races during International Competition

Biochemical parameters are useful in the diagnosis of many health abnormalities in athletes. Some studies suggest training well and eating a balanced diet to improve performance. The modification of biochemical parameters during endurance races has not yet been studied in many African countries. Our objective was to evaluate the dietary profile and the effects of competition on the biochemical parameters of Congolese endurance athletes. The method used was the questionnaire for the food profile and blood samples were taken to measure the biochemical parameters of the athletes. A total of 64 athletes, i.e. 20 girls and 44 boys divided into two groups (group 1 or experimental group (EG), 32 endurance athletes and group 2 or control group (CG), 32 walkers who participated in a cross-sectional study in Brazzaville. The subjects were respectively 26.16 ± 2.79 years old for the EG and 27.44 ± 3.34 years old for the CG. The results indicated that quality foods were difficult to access. The main course was more consumed compared to the starter and dessert (60% of girls and 63.63 of boys). However, biochemical parameters showed a significantly lower serum creatinine concentration in EG subjects compared to CG subjects (0.86 ± 0.06 mg/dl vs 1.04 ± 0.16 mg/dl; t = ?5.95; p 0.05). Similarly, Total Cholesterol was significantly low (1.66 ± 0.34 g/l vs 2.09 ± 0.50 g/l; t = ?3.99; p < 0.000). Cholesterol concentrations of EG subjects (HDL-C) were significantly elevated (0.98 ± 0.49 g/l vs 0.48 ± 0.18 g/l; t = 5.34; p < 0.000). In conclusion, the biochemical data were normal but the food profile of the runners was unfavorable, inadequate and unbalanced. This is considered to be a performance limiting factor.