The use of electromyography (EMG) is widely recognised as a valuable tool for enhancing the understanding of performance drivers and potential injury risk in sprinting. The timings of muscle ...activations relative to running gait cycle phases and the technology used to obtain muscle activation data during sprinting are of particular interest to scientists and coaches. This review examined the main muscles being analysed by surface EMG (sEMG), their activations and timing, and the technologies used to gather sEMG during sprinting. Electronic databases were searched using 'Electromyography' OR 'EMG' AND 'running' OR 'sprinting'. Based on inclusion criteria, 18 articles were selected for review. While sEMG is widely used in biomechanics, relatively few studies have used sEMG in sprinting due to system constraints. The results demonstrated a focus on the leg muscles, with over 70% of the muscles analysed in the upper leg. This is consistent with the use of tethered and data logging EMG systems and many sprints being performed on treadmills. Through the recent advances in wireless EMG technology, an increase in the studies on high velocity movements such as sprinting is expected and this should allow practitioners to perform the analysis in an ecologically valid environment.
In view of the clinical importance of hypofractionated radiotherapy, track models which are based on multi-hit events are currently reinvestigated. These models are often criticized, because it is ...believed that the probability of multi-track hits is negligible. In this work, the probabilities for one- and multi-track events are determined for different biological targets. The obtained probabilities can be used with nano-dosimetric cluster size distributions to obtain the parameters of track models. We quantitatively determined the probabilities for one- and multi-track events for 100, 500 and 1000 keV electrons, respectively. It is assumed that the single tracks are statistically independent and follow a Poisson distribution. Three different biological targets were investigated: (1) a DNA strand (2 nm scale); (2) two adjacent chromatin fibers (60 nm); and (3) fiber loops (300 nm). It was shown that the probabilities for one- and multi-track events are increasing with energy, size of the sensitive target structure, and dose. For a 2 × 2 × 2 nm
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target, one-track events are around 10,000 times more frequent than multi-track events. If the size of the sensitive structure is increased to 100–300 nm, the probabilities for one- and multi-track events are of the same order of magnitude. It was shown that target theories can play a role for describing radiation-induced cell death if the targets are of the size of two adjacent chromatin fibers or fiber loops. The obtained probabilities can be used together with the nano-dosimetric cluster size distributions to determine model parameters for target theories.
Introduction: Issues related to the classification in sport of people with disabilities is one of the major area of research in this field. Looking to objective criteria for assessing functional ...capabilities of the players, in order to allow them a fair competition, where impact on the achieved result is performance, and not the type and degree of disability. Material and methods: Analysis of the sports results obtained at the Paralympic Games (PG) in the years 2000-2012 was aimed to assess the classification system in Track & Field (TF). Material were sports results, based on official reports, obtained by athletes with locomotor disability (LD) in the track events during PG in the years 2000-2012. To determine the difference in results between starting classes the U Mann - Whitney test was used. Statistical significance was set at p <0.05. Results: The largest difference in the results obtained by the athletes (men) with similar functional capabilities was observed among competing on the wheelchair. No statistically significant differences between the results of the runners competing in the standing position was observed in T38 and T44 classes in 400m, throughout the entire period. A similar level of the results observed in women from T53 and T54 class practicing athletics sprint events. Conclusions: The specificity of the discipline that is the TF (a large number of events with various type of effort) can cause problems in the evaluation of the classification system, which doesn't take into account the event in which athletes compete.
The collection of retrospective lap times from video footage is a potentially useful research tool to analyze the pacing strategies in any number of competitive events. The aim of this study was to ...validate a novel method of obtaining running split-time data from publically available video footage. Videos of the 1500-m men's final from the 2004 and 2008 Olympics, 2005 and 2009 World Championships, and 2010 European Championships were obtained from the YouTube Web site, and split times were collected from all competitors using frame-by-frame playback. The typical error of video split times ranged between 0.02 s and 0.11 s for the 4 laps when compared with official split times. Video finishing times were also similar to official finishing times (typical error of 0.04 s). The method was shown to be highly reliable with a typical error of 0.02 s when the same video was analyzed on 2 occasions separated by 8 mo. Video data of track races are widely available; however, camera angles are not always perpendicular to the start/finish line, and some slower athletes may cross the line after the camera has panned away. Nevertheless, the typical errors reported here show that when appropriate camera angles are available this method is both valid and reliable.
Sports track events are the major events in sports competition and have been the major ways of peoples participation in sports. As technology advances and managerial concept changes, the ...digitalization, intelligentization and automation of management has become an unavoidable trend for track events. As a major component of track events managerial automation, automatic circle-counting system has been attached great importance by the sports circle. Based on these developmental changes in track events management, this paper analyses the core part of automatic circle-counting system in track events, that is the research and design of information processing, with special focus on the analysis of its influence on electronic circuit, processing module and data base. This research aims to ;perfect the design of information processing with improved function, rationalized interface design, solid framework and simple operation so as to provide scientific and efficient service to track events and promote actively the IT level of track events management.
Provider: - Institution: - Data provided by Europeana Collections- sisällön kuvaus: Suomalainen juoksija Kaarlo Maaninka (vas.) kolmantena 5000 metrin juoksun maaliviivalla Moskovan olympialaisissa ...1.8.1980. Etiopian Miruts Yifter (kesk.) voitti olympiakultaa ja tansanialainen Suleiman Nyambui (oik.) tuli toiseksi.- content description: Finnish runner Kaarlo Maaninka (left) was third on the 5 000 meter finish line at the Moscow Olympics on August 1, 1980. Ethiopian Miruts Yifter (center) won Olympic gold and Tanzanian Suleiman Nyambui (right) came in second.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
This work aims at elaborating the basic assumptions behind the “track-event theory” (TET) and its derivate “radiation action model based on nanodosimetry” (RAMN) by clearly distinguishing between ...effects of tracks at the cellular level and the induction of lesions in subcellular targets. It is demonstrated that the model assumptions of Poisson distribution and statistical independence of the frequency of single and clustered DNA lesions are dispensable for multi-event distributions because they follow from the Poisson distribution of the number of tracks affecting the considered target volume. It is also shown that making these assumptions for the single-event distributions of the number of lethal and sublethal lesions within a cell would lead to an essentially exponential dose dependence of survival for practically relevant values of the absorbed dose. Furthermore, it is elucidated that the model equation used for consideration of repair within the TET is based on the assumption that DNA lesions induced by different tracks are repaired independently. Consequently, the model equation is presumably inconsistent with the model assumptions and requires an additional model parameter. Furthermore, the methodology for deriving model parameters from nanodosimetric properties of particle track structure is critically assessed. Based on data from proton track simulations it is shown that the assumption of statistically independent targets leads to the prediction of negligible frequency of clustered DNA damage. An approach is outlined how track structure could be considered in determining the model parameters, and the implications for TET and RAMN are discussed.
A radiation action model based on nanodosimetry is presented. It is motivated by the finding that the biological effects of various types of ionizing radiation lack a consistent relation with ...absorbed dose. It is postulated that the common fundamental cause of these effects is the production of elementary sublesions (DSB), which are created at a rate that is proportional to the probability to produce more than two ionisations within a volume of 10 base pairs of the DNA. The concepts of nanodosimetry allow for a quantitative characterization of this process in terms of the cumulative probability
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. The induced sublesions can interact in two ways to produce lethal damage. First, if two or more sublesions accumulate in a locally limited spherical volume of 3–10 nm in diameter, clustered DNA damage is produced. Second, consequent interactions or rearrangements of some of the initial damage over larger distances (~ µm) can produce additional lethal damage. From the comparison of theoretical predictions deduced from this concept with experimental data on relative biological effectiveness, a cluster volume with a diameter of 7.5 nm could be determined. It is shown that, for electrons, the predictions agree well with experimental data over a wide energy range. The only free parameter needed to model cell survival is the intersection cross-section which includes all relevant cell-specific factors. Using ultra-soft X-rays it could be shown that the energy dependence of cell survival is directly governed by the nanodosimetric characteristics of the radiation track structure. The cell survival model derived in this work exhibits exponential cell survival at a high dose and a finite gradient of cell survival at vanishing dose, as well as the dependence on dose-rate.
For the traditional data cleaning algorithms mainly fill up the data based on the space-time relevance in the data level, they are not suitable for RFID application scenarios with track information ...based on multi-logical areas. This paper proposed a track data filling algorithm based on movement recency by studying the characteristics of RFID track data. This algorithm maintains a track event tree according to the historical data, to predict the future data and guide the data cleaning. Also it considers the effect on the movement rules from time factor and brings in the ageing factor for maintaining the track event tree, which improved the predict accuracy of the tree and raise the veracity of the filling algorithm.
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