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This study compared the weekly training load (TL) variation across different measures. Fifty-two runners reported their heart rate and distance ran for each training session during four weeks of training. Heart rate measures were used to calculate the weekly TRaining IMPulse (W-TRIMP), whereas the distance ran was used to calculate the weekly distance covered (W-DIST). At the end of each week, participants reported their weekly perceived TL (W-RPE). W-DIST was analyzed alone and combined with W-RPE and W-TRIMP. The weekly overall TL variation was compared using paired-t tests. Compared to W-DIST, the W-RPE (ES: −0.29), W-DIST combined with W-RPE (ES: −0.40) and W-DIST combined with W-TRIMP (ES: −0.31) presented a significant difference in week-to-week overall TL variation. Our results suggest that running coach and athletes include, at minimum, an RPE-based TL measure combined with W-DIST in their training routines. [ABSTRACT FROM AUTHOR]

This case study aims to examine changes in the lower limb joint kinematic profile and performance stability induced by repeated ski runs in two world‐class alpine skiers. Two Olympic medallist alpine skiers were tested during their slalom training, with continuous recording of right knee and hip angles, along with turn time and run time. The eight runs of the training session were analysed with linear mixed models. Results showed no effect of runs repetition on performance (i.e., run and turn time; P ≥ 0.279). There was no global effect of runs repetition on minimal and maximal angles for either the knee or the hip (P > 0.151). There was an interaction between run and leg for the maximal angle of both the knee and hip (P ≤ 0.047), which increased across runs for the outside leg and decreased for the inside leg. The maximal angular velocity for both the knee and hip increased with runs repetition in extension (P ≤ 0.028). There were no overall changes in maximal angular velocity in flexion with runs repetition (P ≥ 0.264), but there was an interaction between run and leg for the knee (P < 0.001) due to faster eccentric velocities across runs for the outside leg and slower velocities for the inside leg. In conclusion, the observed joint kinematic alterations without concomitant performance impairment support the concept of multiple movement strategies in athletes to achieve similar performance, especially under fatigue conditions. [ABSTRACT FROM AUTHOR]

Blood lactate concentration during exercise is a reliable indicator of energy metabolism and endurance performance. Lactate is also present in sweat, and sweating plays an important role in thermoregulation, especially in hot conditions. Recently, wearable sensors have enabled the real-time and noninvasive measurement of sweat lactate concentration, potentially serving as an alternative indicator of blood lactate response. However, the evidence regarding the relationship between sweat and blood lactate responses during incremental exercise in hot conditions is lacking. In a randomized cross-over design, six highly trained male runners completed two incremental treadmill tests under normal (20°C/50%RH) or hot (30°C/50%RH) conditions. The tests include 3-min running stages and 1-min recovery, starting at 12 km/h and increasing by 1 km/h at each stage. Blood and sweat lactate concentrations were measured at each stage to determine blood and sweat lactate thresholds (LT). Blood lactate concentrations were higher under hot conditions (p < 0.01), but there was no difference in the response pattern or velocity at blood LT between conditions. Significant early increase (p < 0.01) in sweat lactate and low velocity at sweat LT (p < 0.05) were observed under hot conditions. A significant correlation between blood and sweat lactate concentrations was found under normal conditions (p < 0.001) but not under hot conditions, and no significant correlations were observed between the velocity at blood and sweat LT. In conclusion, sweat lactate concentration does not consistently reflect blood lactate concentration during incremental exercise. [ABSTRACT FROM AUTHOR]

This paper presents our efforts and subsequent reflections in attempting to make Foucauldian theory accessible and relevant to a group of high-performance endurance-running coaches within the context of a coach development intravention and Foucauldian inspired workshop series. Specifically, we reflect upon our efforts to introduce coaches to Foucauldian ideas and concepts such as the knowledge–power–practice triad and upon the tensions we experienced in doing so. These tensions were related to the power of the theory–practice divide to set expectations around what it means to be an effective coach developer and a high-performance coach but also in the main related to our intentions regarding a broader shift in the coaches' thinking concerning the influence of a number of social forces in the formation of their practices. We contend that coaching scholars invested in mobilizing ways of knowing underpinned by a different logic (e.g., relationally informed ways of knowing) within coaching and coach development settings would benefit from a deeper understanding of the politics of sports coaching knowledge and practice and how relations of power–knowledge impact learning within pedagogical contexts. Such an awareness, we believe, would in turn support more targeted pedagogical frameworks, practices, and strategies specifically aimed at disrupting established relations of power–knowledge and related problematic binary understandings such as the theory–practice divide which stand in the way of more diverse and ethical knowledge production processes in sports coaching and coach development work. [ABSTRACT FROM AUTHOR]

(1) Background: Physical activity may cause an imbalance in the major functions of the human body. This study aimed to investigate the effects of endurance running training on the parameters of the antioxidant defense system (SOD, CAT, GPx, GR, GSH), LPO (malondialdehyde, MDA), and stress hormones (A, NA) in young healthy, previously untrained men. (2) Methods: The training program was as follows: 8 weeks of running, three times per week; the duration of a single session was 30–70 min, the intensity was twice a week in the so-called extensive endurance zone, and once a week in the anaerobic threshold zone. Blood samples were collected from the subjects, before and after the running program. (3) Results: The training program resulted in a significant increase in maximal oxygen consumption (p < 0.001). The activities of SOD, GPx, and GR also increased significantly (p < 0.05, p < 0.01, and p < 0.05, respectively), while CAT activity and GSH and MDA concentrations remained unchanged. The concentration of A decreased (p < 0.05), while the NA concentration increased significantly (p < 0.05). SOD, GPx, GR, and NA positively correlated with VO2max (p < 0.05, p < 0.001, p < 0.01, p < 0.05, respectively), while a negative correlation was detected between A and VO2max (p < 0.05). (4) Conclusions: These results indicate that there is no persistent oxidative stress in response to the applied 8-week running program, probably due to exercise-induced protective alterations in the antioxidant defense system. Furthermore, adaptations occurred at the hormonal level, making the organism more ready for a new challenge. [ABSTRACT FROM AUTHOR]

The development tendency of lightweight and higher-speed regarding trains goes against the safety and comfort requirement of high-speed trains, especially in the scenario of the train running on bridges within crosswind environments. Wind barriers have been proven to be an effective measure to guarantee the train's operation security. In this paper, a new type of wind barrier consisting of the fence-type wind barrier form and open hole-type wind barrier form has been proposed. Then, a series of wind tunnel tests about the large-scale section model of a large-span suspension bridge installed with different wind barriers have been conducted. The effects of three different forms of wind barrier including fence-type, open hole-type, and combined-type on the aerodynamic characteristics of the train-bridge system have been analyzed. The windproofing effectiveness and the protection mechanism of the combined-type wind barrier on the train-bridge system have been revealed through the measured aerodynamic characteristics. The results show that the installation of open hole-type, fence-type, and combined-type wind barriers at a height of 4 m and a ventilation rate of 19% yields a maximum reduction in the train drag coefficient of 67.70%, 72.92%, and 97.21%, respectively. Moreover, the combined-type wind barrier can improve the train-bridge system's aerodynamic performance and trains' running safety on bridges when comparing with the open hole-type and fence-type wind barriers. The proposed combined-type wind barrier can provide a more efficiency and practical way for the high-speed train's running safety on the bridge. [ABSTRACT FROM AUTHOR]

The derailment of a high‐speed train is a complex and uncertain dynamic process, especially under running conditions where the derailment index lacks comprehensive experimental validation. This research focuses on elucidating the mechanism of an earthquake‐induced train derailment and validating the structural response‐based spectrum intensity derailment index. To achieve this, a multi‐array shaking table system was utilized to test the safety of a running train and to physically replicate train derailment process under severe earthquake impact. We investigated the vibration characteristics and derailment progression of trains operating at different speeds, exposed to earthquakes of varying frequencies and intensities. In stationary derailments, significant wheelset lift was observed due to lateral rolling vibrations. However, in running test cases, there was no separation between the wheels and rails. Instead, the wheels underwent a long period of climbing and descending on the rails, similar to damped single‐degree‐of‐freedom oscillations. As the wheel climbed the rail and reached a critical potential energy point, the wheel flange of the wheel could potentially fall due to gravity or come off the rail due to external disturbances. The critical potential energy could be represented by the spectrum intensity threshold, and the prediction results aligned well with the derailment test results for both stationary and running trains. Furthermore, the method of determining train derailment based on structural responses was consistent with the test results. The spectrum intensity index shows strong positive correlations with other wheel‐force‐related indicators, albeit adopting a conservative perspective, reinforcing its efficacy in assessing train safety. [ABSTRACT FROM AUTHOR]

The uneven subgrade settlement affects the running of high-speed trains on slab tracks. However, the dynamics for the coupling system under subgrade settlement lack in-depth research. A nonlinear train-CRTS III slab track coupling dynamic model under uneven subgrade settlement, which considers the interface contact nonlinearity, is developed in ANSYS and validated by a MATLAB program. The initial track statuses and system dynamics under different settlement amplitudes and positions are extensively researched and analyzed using the model. Some conclusions are drawn: (1) Voids occur in slab track with large subgrade settlements, and nonlinear contact elements are needed to model them. (2) The ratios of initial statuses of slab track induced by uneven subgrade settlement are high for most items. (3) The maximum response distributions differ for different items. Some occur around the settlement boundaries. (4) The effect laws of settlement amplitude and position on the system dynamics differ for different items. (5) The tension force of fastener, tension stress of concrete base, and pressure stress on subgrade will exceed the allowable value when the uneven settlement amplitudes exceed 17, 11, and 18mm, respectively. [ABSTRACT FROM AUTHOR]

The purpose of this study was to (a) correlate the weekly external training load with the game running performance in season microcycles and (b) specify the optimal training/game ratio of the weekly external load in elite youth soccer players. The total distance (TD), the high-speed running distance (HSRD) (19.8–25.2 km/h), the ZONE6 distance (>25.2 km/h), the acceleration (ACC) (≥+2 m/s2), and the deceleration (DEC) (≥−2 m/s2) were monitored with global positioning system (GPS) technology throughout 18 microcycles and official games. TD had a very high positive correlation average (r = 0.820, p = 0.001), the HSRD had a high positive correlation average (r = 0.658, p = 0.001), the ZONE6 distance and DEC had a moderate positive correlation average ((r = 0.473, p = 0.001) and (r = 0.478, p = 0.001), respectively), and the ACC had a low positive correlation average (r = 0.364, p = 0.001) between microcycles and games. Regarding the training/game ratio, the HSRD showed statistically significant differences between ratios 1.43 and 2.60 (p = 0.012, p ≤ 0.05), the ACC between ratios 2.42 and 4.45 (p = 0.050, p ≤ 0.05) and ratios 3.29 and 4.45 (p = 0.046, p ≤ 0.05), and the DEC between ratios 2.28 and 3.94 (p = 0.034, p ≤ 0.05). Considering the correlation between weekly training and game external load, high weekly training TD values correspond to higher game values, whereas HSRD, ZONE6 distance, ACC, and DEC, which determine training intensity, should be trained in a specific volume. Training/game ratios of 1.43, 2.42 to 3.29, and 2.28 to 3.11 seem to be optimal for HSRD, ACC, and DEC weekly training, respectively. [ABSTRACT FROM AUTHOR]

Training to run is not straightforward since without proper personalised supervision and planning, people will not improve their performance and will increase the risk of injuries. This study aims to identify the different factors that influence running training programmes, examining the benefits, challenges or limitations of personalised plans. Moreover, this study explores how multimodal, immersive and artificial intelligence technologies can support personalised training. We conducted an exploratory sequential mixed research consisting of interviews with 11 running coaches from different countries and a survey of 12 running coaches. Based on the interviews and survey analysis, we identified and extracted relevant factors of the training process. We identified four relevant aspects for running training: physical, technical, mental and body awareness. Using these aspects as a reference, we derived a framework using a bottom‐up approach. This framework proposes multimodal, immersive and artificial intelligence technologies to facilitate personalised running training. It also allows coaches to personally guide their athletes on each aspect. Practitioner notesWhat is already known about this topic Running is a popular sport that provides health benefits and is practised by many people around the world.Training is a process that enables athletes to improve their development in various aspects of their sport; in the case of running, it helps them to increase their speed and endurance.Personalised training supports the needs and abilities of athletes, by helping them to achieve their potential through individualised activities or programmes.Sports science research indicates that personalised training can be improved by applying technology to tackle its challenges and limitations.What this paper adds We show that personalising the training requires not only focusing on the runners' physical condition but also on their mental, technical and body awareness aspects, where each of them has a different adaptation to training.We show that multimodal and immersive technologies offer suitable and portable ways to measure and target the mental and body awareness aspects during running training.Implications for practice and/or policy This paper presents a list of factors, measures and devices that coaches can use to plan and design their training sessions in a more personalised manner.This study can serve as a foundation for future research that aims to identify and target the various factors that influence the learning and training of sports. [ABSTRACT FROM AUTHOR]

Background: Applying whole-body electromyostimulation (wbEMS) to voluntary activation of the muscle is known to impact motor unit recruitment. Thus, wbEMS as an additional training stimulus enhances force-related capacities. This study aimed to evaluate the mono- and multiarticular strength adaptations to a running intervention with wbEMS compared to running without wbEMS. Methods: In a randomized controlled trial (RCT), 59 healthy participants (32 female/ 27 male, 41 ± 7 years) with minor running experience conducted an eight-week running intervention (2x/ week à 20 min) with a wbEMS suit (EG) or without wbEMS (control group, CG). Maximal isokinetic knee extensor and flexor strength and jump height during countermovement jumps were recorded prior and after the intervention to assess maximal strength and power. Results: Following eight weeks of running, maximal isokinetic knee extension torque decreased significantly over time for both interventions (EG Δ -4%, CG Δ -4%; F(1, 44.14) = 5.96, p = 0.02, η = 0.12). No changes were observed for flexion torque (F(1, 43.20) = 3.93, p = 0.05, η = 0.08) or jump height (F(1, 43.04) = 0.32, p = 0.57, η = 0.01). Conclusions: The outcomes indicate that there is no additional effect over neuromuscular function adaptations with the inclusion of wbEMS during running training. Knee extensor strength is even slightly reduced which supports the principle of training specificity in regards to strength adaptation. We conclude that strength improvements cannot be achieved by running with wbEMS. Trial registration: German Clinical Trials Register, ID DRKS00026827, date 10/26/21. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: The objective of the argument in this paper is to present a summary of the implementation of the Free the Energy! project, the main goal of which was to promote physical activity as one of the important components of a healthy lifestyle and one of the elements of building a sustainable organization. Design/methodology/approach: In the theoretical part of the paper, the definitions of the concept of sustainable development and sustainable organizations, as well as physical activity as one of the main components of a healthy lifestyle, are presented synthetically. The research part presents a summary of the implementation of the Free the Energy! project, the main goal of which was to promote physical activity as one of the important components of a healthy lifestyle and one of the elements of building a sustainable organization. The empirical research conducted independently by members of the research team in the form of a case study was devoted to achieving the research objectives. The following selection methods were used: document analysis (regulations, University of Lodz strategy, project reports) and semistructured, in-depth interviews conducted with participants of running training carried out as part of the “Free the Energy!” Findings: The analysis of the research results confirms the achievement of the goals of Free the Energy! project. The project activities achieved the main goals, i.e. promoting physical activity as one of the main components of a healthy lifestyle and one of the elements of building a sustainable organization. Additionally, the activities undertaken as part of the project had a positive impact on improving the image of the University of Lodz. Social implications: Building awareness among the academic community of what sustainable development is and how to implement sustainable development goals. Practical implications: The results of the research discussed in the paper have many practical implications, which may be an indication for other universities of what selected initiatives to undertake in the area of sustainable development. Originality/value: The paper reveals new aspects that play a crucial role in shaping sustainable universities. [ABSTRACT FROM AUTHOR]

This document presents a study on the relationship between physical characteristics, respiratory muscle capacity, and performance in amateur halfmarathon runners. The aim of this study was to establish a preliminary predictive model to provide insights into training and health management for runners. Participants were recruited from the 2023 Beijing Olympic Forest Park Half-Marathon, comprising 233 individuals. Personal information including age, gender, height, weight, and other relevant factors were collected, and standardized testing methods were used to measure various parameters. Correlation analysis revealed significant associations between gender, height, weight, maximum expiratory pressure, maximal inspiratory pressure, and halfmarathon performance. Several regression equations were developed to estimate the performance of amateur marathon runners, with a focus on gender, weight, maximum expiratory pressure, and height as predictive factors. The study found that respiratory muscle training can delay muscle fatigue and improve athletic performance. Evaluating the level of respiratory muscle capacity in marathon athletes is crucial for defining the potential speed limitations and achieving optimal performance. The information from this study can assist amateur runners in optimizing their training methods and maintaining their physical wellbeing. [ABSTRACT FROM AUTHOR]

This paper explores the potential of Physics-Informed Neural Networks (PINNs) to serve as Reduced Order Models (ROMs) for simulating the flow field within stirred tank reactors (STRs). We solve the two-dimensional stationary Navier-Stokes equations within a geometrically intricate domain and explore methodologies that allow us to integrate additional physical insights into the model. These approaches include imposing the Dirichlet boundary conditions (BCs) strongly and employing domain decomposition (DD), with both overlapping and non-overlapping subdomains. We adapt the Extended Physics-Informed Neural Network (XPINN) approach to solve different sets of equations in distinct subdomains based on the diverse flow characteristics present in each region. Our exploration results in a hierarchy of models spanning various levels of complexity, where the best models exhibit $ \ell_1 $ prediction errors of less than 1% for both pressure and velocity. To illustrate the reproducibility of our approach, we track the errors over repeated independent training runs of the best identified model and show its reliability. Subsequently, by incorporating the stirring rate as a parametric input, we develop a fast-to-evaluate model of the flow capable of interpolating across a wide range of Reynolds numbers. Although we exclusively restrict ourselves to STRs in this work, we conclude that the steps taken to obtain the presented model hierarchy can be transferred to other applications. [ABSTRACT FROM AUTHOR]

We present Svetlana (SuperVised sEgmenTation cLAssifier for NapAri), an open-source Napari plugin dedicated to the manual or automatic classification of segmentation results. A few recent software tools have made it possible to automatically segment complex 2D and 3D objects such as cells in biology with unrivaled performance. However, the subsequent analysis of the results is oftentimes inaccessible to non-specialists. The Svetlana plugin aims at going one step further, by allowing end-users to label the segmented objects and to pick, train and run arbitrary neural network classifiers. The resulting network can then be used for the quantitative analysis of biophysical phenoma. We showcase its performance through challenging problems in 2D and 3D and provide a comprehensive discussion on its strengths and limits. [ABSTRACT FROM AUTHOR]

The void of cement asphalt (CA) mortar layer will aggravate the abnormal vibration of high-speed trains at the void position and threaten the running safety. Few studies have been conducted on the effect of mortar layer void on the dynamic performance of slab track on bridges and the damage limits. Aiming at the practical problem of CA mortar layer void in track-bridge systems, a dynamic response calculation program for the train-track-bridge system is prepared based on the train-track-bridge interaction theory. A sample library of high-speed trains running performance indicators considering random initial track irregularity under CA mortar layer void conditions is constructed. The influence of void length on the dynamic performance of high-speed trains under two different CA mortar layer void conditions is investigated by means of sample upper bounds based on probability guarantee rate. The results show that the wheel load reduction rate and vertical acceleration of high-speed trains are more sensitive to changes in void length than the derailment coefficient. The effect of CA mortar layer void on the running performance index of high-speed trains is significantly enhanced after a certain critical void length value, railway maintenance should pay more attention to critical thresholds. The mid-span void and beam-end void length thresholds of CA mortar layer based on the probability guarantee rate decrease significantly with the increase in running speed while utilizing the wheel load reduction rate as the control index. However, the void position has little influence on the void length threshold. The void length threshold results can provide a basis for the CA mortar void limits. [ABSTRACT FROM AUTHOR]

Background The problem of developing the speed of movement and speed-strength qualities of sprinters can be solved by applying special exercises in artificially difficult training conditions. The purpose of the study is to explore the possibilities of using special training tools, in particular running in artificially difficult conditions at the stage of special physical training of sprinters of mass categories. Materials and Methods The study involved young men aged 17-19 years old in the number of 28 people who were engaged in sprint running in the athletics section at the sports school of the Olympic reserve of the city of Kirov (Russia). The pedagogical experiment began on November 5, 2022 and ended on May 24, 2023. By the method of random sampling, all athletes were differentiated into a control group that practiced according to the standard methodology for training sprinters in natural conditions of difficulty and an experimental group in which sprinters practiced in artificially created conditions of difficulty. When processing the results of the study, the Student's T-test was used. Results After the end of the pedagogical experiment, the indicators in both groups improved. The sprinters from the control group had higher scores from 1% to 3% in all tests (p>0.05). In the athletes from the experimental group, from the beginning to the end of the study, the indicators improved from 4.5% to 5.9% on all tests (p<0.05). This proves the effectiveness of using a set of exercises and load components in working with athletes in artificially created difficult exercise conditions. Conclusion If you use a special set of exercises in artificially created difficult conditions when working with sprinters aged 17-19, then the indicators of speed and strength abilities and speed of movement will significantly improve in comparison with athletes who train in natural conditions of difficulty. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As cities have grown, conductor rail power supplies have been widely used in the field of urban rail transit. In order to improve the running performance of trains and reduce the occurrence of accidents, it is necessary to understand the vibration of shoegear-rail system under different initial contact forces and explore the dynamic performance of shoegear-rail system. Therefore, according to the structure of shoegear-rail system, a coupling model of shoegear-rail system is established in this paper. On the basis of the model, the numerical simulation of the shoegear-rail system under different initial contact forces is carried out, and finally the vibration data of the shoegear-rail system under different initial contact forces are obtained. The results show that with the increase of initial contact force in the range of 70–160 N, the vibration amplitude of the electric shoegear and the fluctuation amplitude of the contact force increase, but the maximum absolute shear force value of the conductor rail decreases. It indicates that the lower initial contact force, the better the performance of shoegear-rail system. [ABSTRACT FROM AUTHOR]

Introduction The aim is to investigate the impact of large-group, motor learning–based running gait training on injury risk in United States Air Force (USAF) Basic Military Training (BMT). Design A prospective quasi-experimental program evaluation is used. Materials and Methods Medical providers taught running gait form to groups of trainees in the first week of training of BMT from August 2020 to March 2021. The main outcome measures included risk ratio of reported injuries, removal from training because of injury, and separation from service because of injury. Results Of BMT trainees, 2,205 underwent group, motor learning–based running gait training; this was compared with two intake groups (n A = 3,941 and n B = 2,041) who were only given introductions to sports medicine staff in a classroom setting. Reported pain complaints increased (χ2 = 27.4A and 20.83B, P  < .001). Risk ratios for more severe injuries necessitating time out of training or separation from USAF were reduced, although these were statistically not significant (13%, P  = .48 and 22%, P  = .29, respectively). Leadership implemented gait training across BMT, and data from the following 8 weeks of intake (n  = 6,223) demonstrated similar trends in increases in patient reports of pain (χ2 = 67.25, P  < .001) but significantly reduced risk ratios of removal from training (32%, χ2 = 16.35, P  < .001) or separation (32%, χ2 = 12.54, P  < .001). Conclusions While not previously shown to mitigate injury, large-group, running gait training was associated with a significant reduction in injury severity defined by training delays and separation from service in USAF BMT. [ABSTRACT FROM AUTHOR]

Copyright of English Teaching & Learning is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Professional rugby union players can improve their performance by engaging in small-sided games (SSGs), which simulate the movement patterns of the game. This study collected metrics related to running performance and mechanical workload and their relative values from both forward and back positions, aiming to explore the impact of different SSGs factors on athlete workload, as well as the workload difference between official games (OGs) and SSGs. Methods: The monitored GPS data were collected from SSGs with different player numbers and pitch sizes (five sessions), SSG rules (5 weeks, four sessions per week), and OGs conducted throughout the year. Additionally, the study compared changes in players' sprinting performance before and after two SSG sessions. Results: Backs had greater workload than forwards. Less space and number of players SSG (4 vs. 4, 660m²) was conducive to facilitating training for players in acceleration and deceleration. Conversely, larger spaces were associated with improved running performance. However, the introduction of a floater had no significant impact on performance improvement. Additionally, the 7 vs. 4 model (seven players engaged with four opponents) resulted in the greatest workload during medium-hard accelerations (F = 52.76-88.23, p < 0.001, ηp² = 0.19-0.28). Japan touch model allowed for more high-speed running training (F = 47.93-243.55, p < 0.001, ηp² = 1.52). The workload performed by SSGs can almost cover that of OGs (F = 23.36-454.21, p < 0.05, ηp² = 0.03-0.57). In the context of ηp², values around 0.01, 0.06 and 0.14 indicate small, medium and large effects respectively. Discussion: However, given the significantly higher workload of SSGs and the slight decrease in sprinting performance, further research is required to examine the training patterns of SSGs. This study provided insight into the impact of player numbers, pitch size, and rules on rugby-specific SSGs. Coaches should optimize SSG setups for enhanced training outcomes, ensuring the long-term development of physical capacity, technical and tactical skills. [ABSTRACT FROM AUTHOR]

The effects of long-term omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation during endurance training on tryptophan (Trp) metabolism and mental state of healthy individuals have not been evaluated so far. Concentrations of plasma Trp, its metabolites and IL-6 were assessed in 26 male runners before and after a 12-week training program combined with supplementation of n-3 PUFAs (O-3 + TRAIN group) or medium chain triglycerides (MCTs; TRAIN group). After the 12-week program participants' mood before and after stress induction was also assessed. The effects of the same supplementation protocol were evaluated also in 14 inactive subjects (O-3 + SEDEN group). Concentrations of 3-hydroxykynurenine (3-HK) and picolinic acid (PA) significantly increased only in the O-3 + TRAIN group (p = 0.01; η p 2 = 0.22 and p = 0.01; η p 2 = 0.26). Favorable, but not statistically significant changes in the concentrations of kynurenic acid (KYNA) (p = 0.06; η p 2 = 0.14), xanthurenic acid (XA) (p = 0.07; η p 2 = 0.13) and 3-hydroxyanthranilic acid (3-HAA) (p = 0.06; η p 2 = 0.15) and in the ratio of neurotoxic to neuroprotective metabolites were seen also only in the O-3 + TRAIN group. No changes in mood and IL-6 concentrations were observed in either group. Supplementation with n-3 PUFAs during endurance training has beneficial effects on Trp's neuroprotective metabolites. Trial registry: This study was registered at ClinicalTrials.gov with identifier NCT05520437 (14/07/2021 first trial registration and 2018/31/N/NZ7/02962 second trial registration). [ABSTRACT FROM AUTHOR]

This paper establishes a simplified model of train approach at level crossings under the British standards system. On this basis, it analyzes the running state of trains approaching level crossings, to obtain the level crossing alarm time for automatic level crossings under different initial speeds. It analyzes the key influencing factors of the level crossing alarm time for train approach in the multi-level-crossing section. It also analyzes the train departure interval in the double-track multi-level-crossing section, to obtain the calculation method of the train departure interval for train operation in opposite directions. Moreover, it performs simulation calculation using MATLAB under the simulated scenario of train operation in the multi-level crossing section, to obtain the optimal train departure interval under this simulated scenario. [ABSTRACT FROM AUTHOR]

Background: Although runner’s profiles were previously investigated, information on the training frequency and training distance for short (5 km, 10 km) and long-distance (>21 km) running is absent. The present study aimed to investigate the associations between training routines and exercise habits of recreational endurance runners considering self-reported preferred race distance [10 km, half-marathon (HM), and marathon/ultra-marathon (M/UM)] subgroups. Methods: This is a cross-sectional study, sampling 154 recreational runners of both sexes. A web survey was used for data collection regarding age, sex, preferred distance (10-km, HM, M/UM), training routines, exercise habits, and periodized training routines. The Chi-square test (Cramer’s V) and Kruskal-Wallis test (Eta-Squared η²) with effect sizes were used for comparisons between race distances. Results: Significant differences were shown for anthropometric, training, and periodization characteristics. Highly significant differences were found between subgroups for the number of sessions, running kilometers, and training hours at all periods and within all four preparation conditions. M/ UM runners were training more frequently, for longer durations, and ran greater distances each week. Conclusion: This finding supports the notion that training habits and periodization characteristics are different for different race distances (10- km, half marathon, marathon, and ultramarathon). [ABSTRACT FROM AUTHOR]

With global warming intensifying, weather patterns become more volatile and extremes more common. Tornadoes are the most destructive natural disasters causing significant damage to infrastructure. Meanwhile, high-speed railways now face greater risks from tornado events as the national railway network and mass transit trains expand. Thus, studying the tornado flow characteristics and associated effects on high-speed trains is necessary. A study is presented regarding the wind-loading characteristics of a high-speed train running over a railway bridge induced by a tornado belonging to the future railway network. The wind-loading characteristics analyses are performed using the improved delayed detached eddy simulation method. After verifying the numerical approach and mesh strategy, computational studies are conducted to produce a tornado-like vortex and investigate the tornado-induced wind-loading characteristics of a high-speed train running on the bridge by combining a tornado simulation with a moving mesh technique. For the wind-loading parameters studied herein, the selected train's velocity range is between 50 and 350 km/h, the typical operation speed of either regular or high-speed trains. The numerical results show that the time histories of aerodynamic forces on the train revealed a pattern in tornadic flow variability, the time evolutions of the wind loads on the train were affected by train speeds, and the fluctuation was the greatest when the train ran at 50 km/h. Moreover, the train is subjected to larger aerodynamic forces and moments when it operates along with the rotating vortex flow, especially in the core region, and the train is more dangerous when it runs at a lower speed. The results in this study provide references for assessing operation safety, while a train running on the bridge encounters tornadoes. [ABSTRACT FROM AUTHOR]

In this paper, a vehicle track coupling dynamic model including bearing outer ring defects is built, the time history of the axle‐box vibration acceleration and the time history of the bearing roller‐outer raceway contact load under the condition of random track irregularity on the Beijing‐Tianjin line are obtained by simulation calculation. The results show that when the outer ring defect of the bearing occurs, the axle box will generate high‐frequency vibration at the resonance peak in the vertical and lateral directions. When the defect on the bearing outer ring is in the small width of 1 mm, the roller only imposes one impact when passing through the defect area. However, when the width exceeds 3 mm, the large defect causes the roller to impose a double impact on the lateral direction of the axle box, due to changes in bearing clearance in the passing‐through process. When the running speed of the train is about 250 km h−1, the width of bearing outer ring defects needs to be limited to within 1 mm, to minimize a series of problems such as structural fatigue caused by the increased bearing roller‐outer raceway contact load caused by bearing outer ring defects. [ABSTRACT FROM AUTHOR]

Background: Running-related injuries (RRI) are common in novice runners. Reducing early training running volume with strengthening activities may improve RRI without impeding running performance. Objectives: 1. Gather feasibility data for a randomized, controlled trial comparing a strengthening-based program to a conventional running program; 2. Assess RRI; and 3. Assess running performance. Methods: Seventy-four university students (38 females, 21 ± 2.3 years, 68.2 ± 10.8 kg, BMI: 22.6 ± 2.97), all novice runners, were randomized in two groups, i.e., a strengthening and running group (INT) and a running group (CON). The completed sessions, RRI, dropout, and maximal aerobic speed were recorded through an online application. Results: The INT group had 52.6% attrition, while the CON group had 41.7%. The INT group had 56.6% adherence, while the CON group had 45.7%. The Chi-square test showed no significant difference in RRI incidence across groups (CHI2 = 2.958, p value = 0.08). A two-way ANOVA showed no significant difference in maximal aerobic speed across groups (p = 0.822) or before and after training (p = 0.304). Conclusions: This pilot study confirmed the feasibility of this randomized, controlled trial with a needed sample size of 194. However, novice runners had greater attrition rates when starting. Based on those limited data, strengthening activities that replaced running volume did not improve RRI or maximal aerobic speed. [ABSTRACT FROM AUTHOR]

Significant disturbances of stray currents caused by subway leakage and unbalanced high-voltage direct current (HVDC) have a significant impact on grounded motors. To obtain the subway leakage current and HVDC ground current, two types of multi-pole distance devices with 6/8 electrodes for orthogonal combination are used. The template matching method is applied to identify the spontaneous potential (SP) pulses generated by subway train start/stop, and daily variation correction is utilized to determine geoelectric field (GEF) step changes caused by HVDC. The results show that (1) the number of SP pulses picked up after template matching corresponds to the number of running trains and the combination of pulses from multiple component orientations reflects the orientation of leakage point; (2) the method for locating current leakage sources can identify the positions of two HVDC converter stations after daily variation correction by analyzing the GEF observation from numerous stations; (3) there are slight dissimilarities between the HVDC simulation and GEF observation due to local electromagnetic environment and electrical structure factors. Therefore, accurate signals of orthogonal observation and positioning methods are crucial for confirming the interference source; after correction in the normal signals, results of good electromagnetic observation can be obtained. [ABSTRACT FROM AUTHOR]

The Virtual Wood Supply Arena is an on-line training environment for managing roundwood purchase, production and transport in cut-to-length supply systems. The purpose of its development was accelerated training for coordination of these functions under realistic operating conditions. It offers 8- and 12-week scenarios for supplying five mills. Weekly planning is done for 10 harvesting teams and 10 trucks in a Swedish case geography while tracking mill delivery fulfillment under weekly trafficability restrictions. The purpose of this paper is to introduce the training environment and report the progression of student performance after 2 years of use in university-level training. Student teams reached full delivery fulfillment within three training runs. After familiarization during an introductory run, a complete 12-week scenario took four effective hours to complete. Delivery fulfillment increased from 82 to 95 and 100% between the first, second and third training runs. The progression of team performance included a 36% reduction of relocation distances for harvesting teams and 11% reduction of transport distances for hauling from forest to mill. By the third training run these performance levels were attained with less than 2 weeks of inventory for both the purchase bank and roadside stocks. [ABSTRACT FROM AUTHOR]

As a novel form of railway transportation, maglev transportation has the advantages of a better curve negotiation ability and grade ability and lower noise and vibration than traditional urban wheel–rail transportation. Thus, it is suitable for use in urban public transportation. However, the levitation of the widely utilized electromagnet suspension (EMS) system relies on continuously active suspension force adjustment, which gives it vehicle–track-coupled vibration characteristics different to those of the traditional wheel–track transportation system. Despite many research studies focusing on maglev vehicle–track coupling vibration, the environmental vibration influences associated with the running of maglev trains are still unclear. When the vibration propagates to the surroundings beyond certain thresholds, it may lead to various vibration serviceability problems. Practical test results on the environmental vibration induced by maglev transportation are still not enough to generate convincing vibration propagation and attenuation laws. In this research, a series of in situ tests were carried out around the Shanghai maglev line; the results show that the viaduct bridge is helpful in reducing environmental vibration, and an empirical formula was proposed to predict the effect of viaduct column height. Due to the ground wave superposition, a vibration-amplifying zone was also found about 10 m away from the maglev line, in which the vibration magnitude was strong enough to be perceived by the surrounding occupants. [ABSTRACT FROM AUTHOR]

Objective: The most important objective was to determine the effect of an aquatic pre-participation training program for improving the running performance of middle-aged marathon runners. Method: The study was conducted among 100 recreational male and female runners (aged 25 to 35 years) fulfilling the inclusion and exclusion criteria. The subjects were randomly divided into two equal groups, the control group (n=50) and the experimental group (n=50) by using SPSS software. 6 weeks of aquatic training was conducted for the experimental group for 5 days per week while the control group underwent swimming. The scores were statistically examined by paired 't-test. Results: Results showed that there was a significant reduction in pain in both groups with a p-value <0.0001. Both groups showed significant improvement in cardiac endurance VO2 max. The mean post-VO2 max of the experimental group and control group showed significant improvement in VO2 max with p-value <0.0001. Experimental group showed more improvement in 1RM leg press test as compared to the control group. Mean pre and post-1RM leg press test was (pre:66.10±14.0) (post:73.40±15.20) with p value <0.0001. While of the control group was (pre:68.02±15.09) (post:69.40±13.94) with p value 0.0275. There was significant improvement in 50m sprint run test in the experimental group with pre mean 6.23±0.44 and post mean 6.00±0.46 with (p value <0.0001). Much improvement was not seen in 50m SRT of the control group, the pre mean was 6.11±0.44 and post mean was 6.06±0.48 with (p value 0.0832). Conclusion: It concluded that the pre-participation aquatic training program had shown a significant positive response in improving speed strength and reducing pain. [ABSTRACT FROM AUTHOR]

The cross-line operation can promote urban rail transit network operation and realize resource sharing. In this regard, the operation mode of running cross-line trains with different compositions on two rail transit lines is proposed. And based on the analysis of passenger travel behavior, the passenger flow allocation model of cross-line operation is proposed. Considering constraints such as the passing capacity of transfer stations and the full load rate of trains, a multi-objective planning model is established with the operating frequencies of different types of trains and the location of the turnaround station as decision variables. The optimization objective is to minimize passenger travel cost and operating costs. Based on the proposed model, an improved quantum genetic algorithm(IQGA) is designed to solve the model, and the Pareto solution of the train plan is solved. Finally, the rationality of the model and algorithm is verified through a case study. The analysis shows that the operation of cross-line trains can make 44.5% of the cross-line passenger flows reach the destination station directly without transferring. And the cross-line routing shares the passenger flows in a balanced way so that the full load rates of each routing are balanced and the passengers travel more comfortably. The average passenger travel cost gradually increases with the increase of the transfer time perception factor. In addition， the setting of the vehicle capacity has a significant influence on the train plan. When making the train plan, the vehicle capacity should be set scientifically and reasonably. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of natural turbulent crosswinds on the aerodynamic loads of a high-speed train (HST) running through a tunnel entrance of high-speed railways, the new contribution is that the changing law of the HST's aerodynamic loads under the incoming turbulence with actual turbulence integral scale is revealed when the HST running in tunnel-flat ground-tunnel scenes, based on two types of turbulence generators with size scaled up by 8 times. The train surface pressure coefficients of the numerical model are compared with the corresponding results of wind tunnel experiments to verify the computational fluid dynamics method. The primary results show that the incoming turbulent flow generated by the spire is consistent with the characteristics of the measured wind. The peak aerodynamic load coefficients of the head carriage increase 1.12–1.5 and 1.06–2.0 times, respectively, under the incoming turbulent flow by the spire and fence, compared to the incoming flow of 11.50 m/s. [ABSTRACT FROM AUTHOR]

The high-speed railway bridge, accounting for over 50% of railway lines, plays an important role in high-speed railways. When the train runs at high speed on these bridges, the strong winds will directly pose a risk to the safety of train operation, even causing train overturning accidents. Therefore, it is significantly urgent to accurately simulate the relative motion of the train-bridge system in crosswind environment. An improved delayed detached-eddy simulation study based on the shear stress transfer k-omega (I-ω) turbulence model was used to analyze the aerodynamic characteristics of trains running on bridges under two relative motion modes, i.e., the static synthesis method (SSM) and the dynamic decomposition method (DDM), and the variation rule of train aerodynamic loads. The differences of aerodynamic forces, surface pressure distributions, and flow characteristics around the train body under two motions were discussed. The results show that the applied velocity-inlet boundaries in two relative train-bridge motion modes under crosswinds lead to a large difference in the flow characteristics around bridges. Compared with the SSM, the DDM generates more small-scale vortices in the leeward side of the train, causes more disturbances, and enhances the flow instability. Under the DDM, the side force coefficient and lift force coefficient of the train are decreased by 1.99%, 66.67% (Train on the windward side) and 24.47%, 48.24% (Train on the leeward side), respectively, as compared to the SSM. The achievements obtained in the current study can provide data support for the operation standard of high-speed trains traveling on bridges. [ABSTRACT FROM AUTHOR]

The cowcatcher is one of the unique devices at the front end of the train, which can remove obstacles on the track by crashing before the vehicle body to ensure the safety of the train. When a collision accident happens, the cowcatcher serves as the first energy-absorbing structure to dissipate and guide the collision energy. The design of the existing cowcatcher of multiple units generally focuses on the good ability to remove obstacles, while the secondary function, the crashworthiness of orderly deformation under collision, still needs further research. In this study, a finite element model of structural static load and collision analysis was established under standard EN 15227, with the cowcatcher for 160 km/h train as the prototype. Then the solution and simulation process was accomplished under the environment of ANSYS and LS-DYNA. The analysis results showed that the structural static strength of the current cowcatcher met the requirements of the standard EN 15227, and the longitudinal stiffness was evenly distributed. When removing the obstacles with low mass, the impact force was small and the structure would not produce obvious deformation; when removing the obstacles with large mass, the impact force was large and the shear fracture might occur at the connection of the cowcatcher. [ABSTRACT FROM AUTHOR]

This study aims to examine: the effect of the hudle drill and zig zag running training models on agility; whether there is an influence of the hurdle drill training model on agility; and whether there is an effect of the zig zag running training model on agility. This research method uses quasi-experiments and the research population is all PFK Angels club players with research samples taken using the total sampling method, so that the research sample is 16 players. The instrument for measuring agility uses the Illimois Agility Test. The data analysis technique used is the T-Test at a significance level of α = 0.05. The results of the study are as follows: (1) There is a significant effect of the hurdle drill and zig zag running training model on agility because the p significance is 0.270 > 0.05 for the pretest and the p significance value is 0.202 > 0.05. (2) there is an effect of the hurdle drill training model on agility because the significance value of p is 6.000 > 0.05 for the pretest and for the posttest the significance of p is 0.001 < 0.05 these results show a significant difference. (3) there is an effect of the zig zag running training model on agility because the p significance value is 3.586 > 0.05 for the pretest and for the posttest the p significance is 0.009 <0.05 these results show a significant difference. [ABSTRACT FROM AUTHOR]

High-speed trains operating in windy areas may accelerate and decelerate frequently to maintain safe travel, especially when passing curves. During acceleration and deceleration, the role of inter-vehicle suspension (IVS) cannot be ignored. The present study aims to evaluate the effect of IVS on the variable speed curve running of trains under crosswinds. To achieve this purpose, a multibody model of a China Railways High-speed 2 (CRH2) high-speed train considering the IVS is established. By inputting the crosswind loads and traction or braking forces to the model and setting curved tracks with different radii and the unloading factor set as safety criterion, the safe running speeds of the train under different crosswind speeds and different track radii were obtained. The difference in the vehicle dynamics considering the IVS and the fixed connection under traction and braking conditions is analyzed. The radius of the curve track significantly affects the safety characteristics of a train under crosswinds, but its impact diminishes for radii greater than 7000 m. The lateral acceleration, movement angle, unloading factor, and derailment coefficient in both acceleration and deceleration cases of car bodies are affected by the IVS. As a consequence, the IVS will lead to lower safe speeds than fixed connections, but it will also convey more realistic and credible train dynamics. [ABSTRACT FROM AUTHOR]

Gastrointestinal (GI) disturbances are a prevalent cause of marathon related complaints, and in extreme cases can promote life-threatening conditions such as exertional heat stroke. Our aim was to study intestinal cell injury [via intestinal fatty acid binding protein (I-FABP)] and perceived GI distress symptoms among marathon runners. We also examined potential risk factors (e.g., inadequate sleep) that could exacerbate GI disturbances in healthy, trained endurance runners. This was a parallel mixed-methods study design. 2019 Boston Marathon participants were recruited via email and subjects completed surveys before the race describing demographics and training history. Participants completed a GI questionnaire to assess presence and severity of symptoms, a survey regarding risk factors (e.g., recent illness, medications) that could promote GI disturbances, and provided a urine sample at three time points (immediately pre-race, post-race, and 24-h post-race). Due to weather, blood samples were only collected immediately and 24-h post-race. A total of 40 runners (males: n = 19, age = 44.9 ± 10.8 years; females: n = 21, age = 44.8 ± 10.6 years) completed this study. I-FABP significantly decreased from postrace (3367.5 ± 2633.5 pg/mL) to 24-h post-race (1657.3 ± 950.7 pg/mL, t (39) = -4.228, p < .001, d = -.669). There was a significant difference in overall GI symptom scores across the three time points (F (2, 39) = 41.37, p < .001). The highest average score occurred post-race (.84 ± .68), compared to pre-race (.09 ± .12) and 24-h post-race (.44 ± .28). Post-race I-FABP (r = .31, p = .048) and post-race urine specific gravity (r = .33, p = .041) were significantly correlated with post-race GI symptom scores. Our study provides further support to the individualized nature of GI disturbances, with participants experiencing a wide range of risk factors that can influence the extent of GI damage and perceived symptoms during and after exercise. [ABSTRACT FROM AUTHOR]