Javelin Throwers Research Articles

Augmented inertial measurements for analysis of javelin throwing mechanics

This paper examines the exploitation of inertial measurements to analyze javelin throwing mechanics. The main objective was to demonstrate that consumer-grade inertial navigation systems, augmented with some position and attitude data obtained from a video sequence, yield detailed information of the mechanics of javelin throwing. Especially, such a system makes it possible to analyze the momentary force and power exerted on the javelin during the acceleration phase. Although the presented system is a pilot, leaving space for further improvements, it already reveals the potential of inertial navigation systems to sports. In practise, an inertial measurement unit was embedded inside the tip of the javelin to determine the javelin’s momentary attitude, position, and velocity. Graphs on the speed and angular velocity about the longitudinal axis of the javelin during the whole performance are presented. The maximum estimated release speed and release angular speed were 28.02 m/s and 215.9 rad/s, respectively. The acceleration phase trajectory of the javelin and its deviation from a straight line path are demonstrated. Additionally, the momentary forces and powers are shown and the effect of aerodynamic forces on the projectile is specified. The magnitude of the maximum tangential forces and accelerating powers were 364 N and 9.76 kW. The duration and length of the acceleration phase trajectory varied between 223 and 231 ms, and 2.48 and 2.75 m. To estimate the accuracy of the inertial measurements, the acceleration phase results were compared to measurements made with high-speed cameras.

Physical education through the ages

The Character of Physical Education best can be viewed through the social formation through which humanity has passed. Slave-owning system that was formed less than seven thousand years ago was divided into: the ruling class made up of slave owners and slaves who had no means of production and no authority. Physical education in a slave-owning society has its own specific characteristic and can be said it was even planned and organized and its features can be seen from the example of Sumerians, Hittites, Assyrians and Persians, China, Egypt, Sparta, Athens and Rome. The nations that came in power tended to new knowledge in all areas, and within specific forms of education and physical education. A variety of physical exercises were available only to the ruling class, who could spare time to meet the numerous and varied entertainment content. Pictures on the walls of tombs, various figures from clay, copper and gold reliefs, literary evidence show what was the attitude towards physical exercise. Dancing and music were present at numerous festivals. There were also martial arts, such as: wrestling, boxing, pugilism, and other sports: running, javelin throw, discus throw, jump into the distance and means of rods, ball games, swimming, gymnastics, archery, horseback riding, etc. The greatest popularity in Rome enjoyed the race chariots with two or four horses and gladiatorial combat. The wars, that were constantly waged, and new conquests brought new wealth that was invested in magnificent buildings. In order to maintain a variety of entertainment, circuses, imperial palaces, theaters and triumphal arches were raised. If we compare the achievements of Roman culture with the culture of the ancient Greeks, we can see that the technique, order, discipline and the law are related to Rome, in contrast to art, literature and philosophy related to Greece. It is undisputed that physical education through all these periods was paid a great attention. Physical culture has taken a special place in the arts, a beautiful and healthy body was the ideal of the ancient Greeks, and many artists show in vase painting and sculpture in the form of athletes in full force. Along with the breakdown of the slavery system and the collapse of the Roman Empire, it comes to destruction of the games that have been for centuries means in the hands of the ruling class.

やり投げにおける木製ヤリを使用したときのリリースパラメータへの影響

やり投げにおける木製ヤリを使用したときのリリースパラメータへの影響

FEATURES OF SPORTS PERFORMANCE RELATED INJURIES OF ELITE TRACK AND FIELD ATHLETES IN LITHUANIA

Background. Sports injuries have a huge impact on performance of athletes in competitions. A lot of athletes do not obtain full recovery after injuries, which leads to trauma recurrence or higher severity injuries. Being aware of dominating anatomical regions and frequencies of occurrence of these traumas could help to prevent it and to protect athletes’ health. Methods. In 2013 Lithuanian professional athletes were asked to fill in questionnaires developed by using standardized methodology validated by the IOC and implemented by the IAAF during international track and field competitions. Data were collected, processed and analysed. Results were obtained using statistical methods, significance level of p ≤ .05 was considered statistically significant. Results. We investigated 33 athletes- sprinters and throwers (javelin and discus throwers, shot putters). They had 57 cases of traumatic injuries in one year period (2012–2013). Results of the study showed that injuries of lower extremity statistically significantly dominated comparing with upper extremity and head/trunk in both fields of sport. Injuries by anatomical region were: lower extremity – 67%, upper extremity – 12%, head and trunk – 21%. Most of all were injured: hamstrings 23%, inguinal 10.5%, lumbar 13% area. Comparing traumas between throwers and sprinters groups lower extremity injuries statistically significantly dominated in sprinters group, while upper extremity had been injured only in the throwers’ group. Analysing severity of the injuries we noticed that moderate and mild injuries were dominating. Mild and moderate severity injuries appeared leading to a higher risk of re-injury than high severity traumas. Recurrence of the same injury was noticed only in the group of sprinters – 57.9% of sprinters repeatedly suffered mostly from hamstring and inguinal traumas. Conclusions. According to the results of this study, sports medicine physicians could predict potential localization and recurrence of injuries and collaborating with coaches and athletes prepare opportune training programs to avoid harm.

The Effect of Functional Resistance Drills Using Elastic Band on Some of Physical and Kinematic Variables on Release Phase in Javelin Throw Event

The Effect of Functional Resistance Drills Using Elastic Band on Some of Physical and Kinematic Variables on Release Phase in Javelin Throw Event

The fourth dimension: A motoric perspective on the anxiety–performance relationship

ABSTRACTThis article focuses on raising concern that anxiety–performance relationship theory has insufficiently catered for motoric issues during, primarily, closed and self-paced skill execution (e.g., long jump and javelin throw). Following a review of current theory, we address the under-consideration of motoric issues by extending the three-dimensional model put forward by Cheng, Hardy, and Markland (2009) (‘Toward a three-dimensional conceptualization of performance anxiety: Rationale and initial measurement development, Psychology of Sport and Exercise, 10, 271–278). This fourth dimension, termed skill establishment, comprises the level and consistency of movement automaticity together with a performer's confidence in this specific process, as providing a degree of robustness against negative anxiety effects. To exemplify this motoric influence, we then offer insight regarding current theories’ misrepresentation that a self-focus of attention toward an already well-learned skill always leads to a negative performance effect. In doing so, we draw upon applied literature to distinguish between positive and negative self-foci and suggest that on what and how a performer directs their attention is crucial to the interaction with skill establishment and, therefore, performance. Finally, implications for skill acquisition research are provided. Accordingly, we suggest a positive potential flow from applied/translational to fundamental/theory-generating research in sport which can serve to freshen and usefully redirect investigation into this long-considered but still insufficiently understood concept.

Evaluation Model for the Performance of Javelin Throw in Accordance with the Mechanical Profile for the High Level in Track and Field

Evaluation Model for the Performance of Javelin Throw in Accordance with the Mechanical Profile for the High Level in Track and Field

Modelling analysis and prediction of women javelin throw results in the years 1946 - 2013.

The main goals of our study of the women’s javelin throw were twofold:. first, to analyse the dynamics of female javelin throw results variability as a function of time (time period 1946-2014), second, to create a predictive model of the results during the upcoming 4 years. The study material consisted of databases covering the female track and field events obtained from the International Association of Athletics Federations. Prior to predicting the magnitude of results change dynamics in the time to follow, the adjustment of trend function to empirical data was tested using the coefficients of convergence. Phase II of the investigation consisted of the construction of predictive models. The greatest decreases in result indexes were noted in 2000 (9.4%), 2005-2006 (8.7%) and 2009 (7.4%). The trend increase was only noted in the years 2006-2008. In general, until 1998 the mean result improved by 54.6% (100% - results of 1946) whereas from 1999 through 2011 the result only increased by 1.3%. Based on data and results variability analysis it might be presumed that, in the nearest future (2015-2018), results variability will increase by approximately 9.7%. Percent improvement of javelin throw distance calculated on the basis of the 1999 raw input data is 1.4% (end of 2014).

The Efficiency of Using Multi-Forms Motor Tasks Style in Learning Javelin Throwing Skills for the Students of the Faculty of Physical Education at Zagazig University

This research aims at identifying the efficiency of using multi-forms motor tasks style (feedback form – video recorder – computer) in learning javelin throwing skills for the second-year undergraduate students at the Faculty of Physical Education for Girls, Zagazig University. The researcher has conducted an empirical study on a sample of (56) second-year undergraduate students at the Faculty of Physical Education for Girls, Zagazig University. They were divided into four groups of (14) students each. The research tools included: physical tests – intelligence test – evaluation of the technical and quantitative performance in javelin throwing - the proposed educational program based on multi-forms motor tasks style.

Biomechanical characteristics of an anterior cruciate ligament injury in javelin throwing

PurposeThe purpose of this study was to understand the mechanism of an anterior cruciate ligament (ACL) injury in javelin throwing and javelin throwing techniques relevant to this ACL injury. MethodsThe patient in this study was an elite female javelin thrower who completed the first three trials and sustained a non-contact ACL injury on her left knee in the fourth trial of javelin throwing during a recent track and field meet. Three-dimensional kinematic data were collected in the injury and non-injury trials. The kinematic data of 52 male and 54 female elite javelin throwers were obtained from a javelin throwing biomechanical database. ResultsThe patient had greater forward center of mass velocity and less vertical center of mass velocity after the first 25% of the delivery phase in the injury trial compared to non-injury trials. The patient had less left knee flexion angle and angular velocity but similar left knee valgus and internal rotation angles during the first 21% of the delivery phase in the injury trial compared to non-injury trials. The video images showed an obvious tibia anterior translation at the 30% of the delivery phase in the injury trial. The left knee flexion angle and angular velocity at the time of the left foot landing and the maximal left knee flexion angle during the delivery phase were not significantly correlated to the official distance for 52 male and 54 female elite javelin throwers. ConclusionThe ACL injury in this study occurred during the first 30% of the delivery phase, most likely during the first 25% of the delivery phase. A stiff landing of the left leg with a small knee flexion angle was the primary contributor to this injury. Javelin throwers may have a soft left leg landing with a flexed knee, which may help them prevent ACL injuries without compromising performance.

Posterior ankle impingement in athletes: Pathogenesis, imaging features and differential diagnoses

Posterior ankle impingement is a clinical diagnosis which can be seen following a traumatic hyper-plantar flexion event and may lead to painful symptoms in athletes such as female dancers (‘en pointe’), football players, javelin throwers and gymnasts. Symptoms of posterior ankle impingement are due to failure to accommodate the reduced interval between the posterosuperior aspect of the talus and tibial plafond during plantar flexion, and can be due to osseous or soft tissue lesions. There are multiple causes of posterior ankle impingement. Most commonly, the structural correlates of impingement relate to post-traumatic synovitis and intra-articular fibrous bands-scar tissue, capsular scarring, or bony prominences. The aims of this pictorial review article is to describe different types of posterior ankle impingement due to traumatic and non-traumatic osseous and soft tissue pathology in athletes, to describe diagnostic imaging strategies of these pathologies, and illustrate their imaging features, including relevant differential diagnoses.

Sports anthropological and somatotypical comparison between young male shotputters and javelin throwers of different performance classes and recreational athletes

This study examines anthropometric and somatotypical differences between German male junior shot putters (n = 19) and javelin throwers (n = 19). Recreational athletes (n = 11) served as the control group (age range 16 – 23 years). Overall, the shot-putters were larger and had longer legs and arms as compared to the junior javelin throwers. For the smaller javelin throwers of the higher performance category shorter legs compared to the height of the hull were observed on average. There was a notably shorter leg of the spear throwers. The powerful javelin throwers had longer arms than the less powerful. For all anthropometric widths and depths, and the circumferences and the body weight, the junior shout putters achieved higher values than the spear throwers and recreational athletes. The skinfold thicknesses, the body fat mass and the BMI were highest among the shot putters. The shot putters had the highest values for endomorphy and pyknomorphia (Knussmann), on the other hand, the lowest values for ectomorphy. For the shot putters body height, shoulder width, hand width, foot width, chest circumference, minimal forearm circumference, calf circumference, arm span, plastic index and macrosomia were positively related to performance. Some skinfolds (calf, thigh) correlated negatively with the shot put distances. For the javelin throwers radiale, stylion, dactylion and ectomorphy correlated negatively with the throw widths, but the AKS index, the BMI, the Quetelet index, the Rohrer index, the Livi index, the Pelidisi index, the Broca index, mesomorphy, the metric index and plastic index correlated positively with the performance. The higher class shot putters of the present study achieved a mean somatotype of 2.9 – 5.6 – 1.1 and the higher class javelin throwers of 2.1 – 4.9 – 1.8. As the shot putters and the javelin throwers of the present investigation were rather young, there is still a significant development potential for the mesomorphic component in comparison to Olympians.

A movable technological simulation system for kinematic analysis to provide immediate accurate feedback and predict javelin throw distance

The use of information technology (IT) and highly sophisticated devices in learning and evaluating training process is very common in today's sport sciences. The research aimed is a Trying to identify using of the biomechanical simulation system to evaluate physical variables in javelin throw. A new movable biomechanical simulation system to expect the javelin throwing distance and evaluate physical variables was developed, which consisted of a 800g sledge to be accelerated along a rope. The release angle can be adjusted within the range of 26 - 40 degrees. The takeoff height can be likewise adapted to the individual conditions of the athlete. By a laser-steered measure (LAVEG) the velocity of the throw carriage can be determined. 20 sport students were selected. The research proves that only 10 seconds are needed to show the expected distance. This research also recommends using this new movable technological biomechanical simulation system in learning and evaluating training processes.

A movable technological simulation system for kinematic analysis to provide immediate accurate feedback and predict javelin throw distance

A movable technological simulation system for kinematic analysis to provide immediate accurate feedback and predict javelin throw distance

Outcomes for ulnar collateral ligament reconstruction: a retrospective review using the KJOC assessment score with two-year follow-up in an overhead throwing population

Injury to the ulnar collateral ligament (UCL) often results in valgus elbow instability requiring reconstruction. No standardized and validated outcome measure has compared outcomes between surgical techniques and institutions in the overhead throwing athlete. The aim of this study was to use the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow score (KJOC score) to report functional outcomes in overhead throwing athletes undergoing UCL reconstruction. We predict that the KJOC score in our general throwing population will provide an accurate assessment of postoperative outcomes consistent with previously published reports. A retrospective review of 33 patients undergoing UCL reconstruction was carried out during a 5-year period between 2004 and 2009. Minimum follow-up was 2.2 years with an average of 3.7 years. All surgeries were performed by fellowship-trained surgeons using either the docking (n = 12) or modified Jobe technique (n = 21). Age, sport, position, and return to play status were obtained. The KJOC score was administered to assess final functional outcome. A total of 33 athletes underwent UCL reconstruction-30 baseball players and 3 javelin throwers. Of these, 27 (82%) returned to their sport at their previous level in an average of 12.25 months. The overall average KJOC score was 76. Athletes who returned to their previous level of play had a mean KJOC score of 77. Those who were unable to return to play had a mean score of 69. Our study demonstrates consistent outcomes for UCL reconstruction using the KJOC shoulder and elbow score compared with previously reported data.

Age-Associated Power Decline from Running, Jumping, and Throwing Male Masters World Records

Background/Study Context: The capacity to perform everyday tasks is directly related to the muscular power the body can develop (see Appendix). The age-related loss of power is a fact, but the characterization or the rate of muscle power loss remains an open issue. Data useful to study the decline of the skeletal muscles power are largely available from sources other than medical tests, e.g., from track and field competitions of Masters athletes. The aim of our study is to identify the age-related decline trend of the power developed by the athletes in carrying out the track and field events.Methods: Absolute male world records of 16 events were collected along with world records of male Masters categories. Performance was normalized with respect to the absolute record; the performance of various age groups is consequently represented by a number ranging from 1 (world absolute records) to 0 (null performance). The performance of a jumping event is transformed into a parameter proportional to the power developed by the athletes: the displacement of the center of gravity of the athlete. Throwing events are further normalized for the decreasing weight of the implements with the increasing age of the Masters athletes.Results: Most track and field events show a linear decline to 70 years. The annual rate of power decline for all the events (running, throwing, and jumping), using a simplified synthesis, is 1.25% per year. The events that involve mostly upper limbs (shot put, javelin throw) show a higher rate of decline (1.4% per year) compared to those where the lower limbs are mostly involved (long jump 1.1%, track events 0.6–0.7% per year). This analysis of muscle power decline is only partially in line with the results of works based on clinical tests. A clarification of the reasons for such discrepancy may provide clinically significant information.Conclusion: Human power decline in Masters athletes was analyzed, adopting a coherent approach based on an extended database. Skeletal muscle power starts declining after the age of 30, with slight variations depending on the events. This conclusion is in line with only some of the previous studies. The various trend lines point to 0 at the age of 110 years, which is in line with the present human survival age. The study can be further developed with a suitable database for male and female Masters performances to facilitate longitudinal studies, which are currently lacking.

Biomechanical characteristics of an anterior cruciate ligament injury in javelin throwing

Biomechanical characteristics of an anterior cruciate ligament injury in javelin throwing

Analysis of world records in the decathlon from 1984 to 2015

The decathlon is a combined event in athletics consisting of ten track and field events, where the most versatile athletes compete. The decathlon competition is held over two days, and the winners are determined by the combined performance in all. On the first day the competitors do 100 m, long jump, shot put, high jump and 400 m. On the second day they do 110 m hurdles, discus throw, pole vault, javelin throw and 1500 m. Performance is judged on a points system in each discipline using scoring tables, which were accepted in 1984 by the International Association of Athletics Federation. Considering that the decathlon stands for running, jumping, and throwing disciplines, the goal of the project is to determine the structure, or domination of definite single disciplines or the group of disciplines, during achieving the world record. According to this, the analysis of world records of five best decathletes Ashton Eaton, Roman Šeble, Tomáš Dvozák, Dan O'Brien and Daley Thompson was done in this project. The research results show that the combination of both achieving average results in disciplines where the decathlete is weaker, and achieving above average results in disciplines which are his strengths is required to achieve top sports results in the decathlon. At the same time, the analysis of world records from 1984 to 2015 show that the world recorders achieved the top results in their own way, but they also show that was not their maximum. According to the analysis of the achieved results, it is expected for Ashton Eaton to achieve the new world record at the Rio 2016 Olympic Games.

The isometric strength comparison of the upper limbs of women from the Czech Republic with a group of sportswomen from various branches

Jurankova, M, Vilim, M., & Janickova, P. (2015). The isometric strength comparison of the upper limbs of women from the Czech Republic with a group of sportswomen from various branches. J. Hum. Sport Exerc., 9(Proc1), pp.S354-S359. The aim of this work was to find out the strength difference of the static flexors of the hand between the dominant and non-dominant upper limbs of sportsmen from chosen branches and general population. A group of 20 sportswomen (10 tennis players and 10 javelin throwers) and a group of general population (252 probands from the whole Czech Republic area) took part in the measuring. All tested people were aged 18 ‐ 29. The measured values (in kg) were obtained by means of a test of handheld dynamometry (digital handheld dynamometer). The measuring showed that sportswomen have higher values of dominant upper limb isometric strength than general population (58.2 kg and 53.8 kg). With the non-dominant upper limb, the situation is reverse: higher values were discovered with general population (51.2 kg) whereas with sportsmen it was only 50.1 kg. A substantially higher difference of isometric strength between the dominant and non-dominant hand was discovered with sportsmen (8.1 kg); this difference is much smaller (2.1 kg) with general population. Key words: HANDHELD DYNAMOMETRY, DOMINANT HAND, NON-DOMINANT HAND, WOMEN.

Comparison of isometric strength men´s upper limbs from the Czech Republic with a group of athletes from different sectors

Vilim, M., Jurankova, M., & Janickova, P. (2015). Comparison of isometric strength mens upper limbs from the Czech Republic with a group of athletes from different sectors. J. Hum. Sport Exerc., 9(Proc1), pp.S308-S313. The aim of this work was to find out the strength difference of the static flexors of the hand between the dominant and non-dominant upper limbs of sportsmen from chosen branches and general population. A group of 20 sportsmen (10 tennis players and 10 javelin throwers) and a group of general population (252 probands from the whole Czech Republic area) took part in the measuring. All tested people were aged 18 - 29. The measured values (in kg) were obtained by means of a test of handheld dynamometry (digital handheld dynamometer). The measuring showed that sportsmen have higher values of dominant upper limb isometric strength than general population (58.2 kg and 53.8 kg). With the non- dominant upper limb, the situation is reverse: higher values were discovered with general population (51.2 kg) whereas with sportsmen it was only 50.1 kg. A substantially higher difference of isometric strength between the dominant and non-dominant hand was discovered with sportsmen (8.1 kg); this difference is much smaller (2.1 kg) with general population. Key words: HANDHELD DYNAMOMETRY, DOMINANT HAND, NON-DOMINANT HAND, MEN.