Javelin Throwers Research Articles

Sequences of upper and lower extremity motions in javelin throwing

Javelin throwing is technically demanding. Sequences of upper and lower extremity motions are important for javelin throwing performance. The purpose of this study was to determine the general sequences of upper and lower extremity motions of elite male and female javelin throwers. Three-dimensional kinematic data were collected for 32 female and 30 male elite javelin throwers during competitions. Shoulder, elbow, wrist, hip, knee, ankle, lower trunk, and upper trunk joint and segment angles were reduced for the best trial of each participant. Beginning times of 6 upper extremity and 10 lower extremity joint and segment angular motions were identified. Sequences of the upper and lower extremity motions were determined through statistical analyses. Upper and lower extremity motions of the male and female elite javelin throwers followed specific sequences (P ≤ 0.050). Upper extremity motions of the male and female elite javelin throwers did not follow a proximal-to-distal sequence as suggested in the literature. Male and female elite javelin throwers apparently employed different sequences for upper and lower extremity motions (P < 0.001). Further studies are needed to determine the effects of sequences of upper and lower extremity motions on javelin throwing performance.

A neural network model approach to athlete selection

In order to determine the usefulness of neural models in optimisation of recruitment processes, statistical analyses were carried out on measured results of javelin throwers using a full take off. A group of 140 Polish junior javelin throwers took part in the research. In order to choose the optimum combination of model parameters the Hellwig method was used. Linear and multilayer perceptron neural models were constructed and used to calculate combinations of variables. Statistical analysis of the results showed that the linear model was not able to describe precisely the relationship between the dependent variable and independent variables for the investigated group of young javelin throwers. For the investigated group, the perceptron network with a 4-3-2-1 structure gave the best predictive relationship for sports results of the javelin throwers.

Is the ‘Crunch Factor’ an Important Consideration in the Aetiology of Lumbar Spine Pathology in Cricket Fast Bowlers?

The 'crunch factor' is defined as the instantaneous product of lateral flexion and axial rotational velocity of the lumbar spine. It was originally implicated in the development of lumbar spine pathology and lower back pain in golfers and, although empirical evidence supporting or refuting the crunch factor is inconclusive, it remains an intuitively appealing concept that requires further investigation, not only in golf, but also in other sports involving hitting and throwing motions. This article considers whether the crunch factor might be instrumental in the aetiology of contralateral lumbar spine injuries sustained by cricket fast bowlers. Based on recent empirical research, it is argued that the crunch factor could be important in cricket fast bowling especially considering that peak crunch factor appears to occur just after front foot impact when ground reaction forces are known to be at their highest. The crunch factor may also occupy an integral role in lower back injuries sustained in other sports involving unilateral overhead throwing (e.g. javelin throwing) and hitting (e.g. tennis serving) actions where the spatial orientation of the arm at release or impact is largely determined by lateral flexion of the trunk and where the transfer of energy and momentum along the kinetic chain is initiated by a rapid rotation of the pelvis. Further research is required to empirically verify the role of the crunch factor in the development of lower back injuries in cricket fast bowling and sports that involve similar lower trunk mechanics. This research programme should ideally be supported by modelling work examining the stresses imposed on bony, disc and joint structures by lateral flexion and axial rotation motions so that their respective contribution to injury can be identified.

Centre of mass kinematics of fast bowling in cricket

Kinematic studies have shown that fast bowlers have run-up velocities, based on centre of mass velocity calculations, which are comparable to elite javelin throwers. In this study, 34 fast bowlers (22.3 ± 3.7 years) of premier grade level and above were tested using a three-dimensional (3-D) motion analysis system (240 Hz). Bowlers were divided into four speed groups: slow-medium, medium, medium-fast, and fast. The mean centre of mass velocity at back foot contact (run-up speed) was 5.3 ± 0.6 m/s. Centre of mass velocity at back foot contact was significantly faster in the fastest two bowling groups compared to the slow-medium bowling group. In addition, stepwise multiple regression analysis showed that the centre of mass deceleration over the delivery stride phase was the strongest predictor of ball speed in the faster bowling groups. In conclusion, centre of mass kinematics are an important determinant of ball speed generation in fast bowlers. In particular, bowlers able to coordinate their bowling action with periods of centre of mass deceleration may be more likely to generate high ball speed.

Oxidative stress and arterial stiffness in strength- and endurance-trained athletes

Background Endurance exercise training decreases arterial stiffness, whereas high-intensity strength exercise training increases arterial stiffness. However, the mechanisms underlying the adaptations to the 2 types of exercise training remain unclear. Increased oxidative stress induces vasoconstriction and endothelial dysfunction. Plasma advanced oxidation protein products (AOPP)—a novel marker of oxidative stress—have recently been reported to be positively associated with arterial stiffness in healthy subjects. We hypothesized that AOPP are involved in the adaptation of arterial stiffness in different types of exercise training. Methods We investigated plasma AOPP concentration and arterial stiffness in strength- and endurance-trained athletes. The subjects included young strength-trained athletes (SA group) (shot put, hammer, or javelin throwers; n = 12), endurance-trained athletes (EA group) (long- or middle-distance runners; n = 10), and sedentary individuals (Control group) ( n = 12). We measured aortic pulse-wave velocity (PWV), systemic arterial compliance (SAC), and plasma AOPP concentrations. Results PWV was higher in the SA than in the EA or control groups (SA: 6.48 ± 0.47, EA: 6.00 ± 0.67, Control: 5.65 ± 0.52 m/s, mean ± SD), and SAC was lower in the SA than in the EA or control groups (SA: 1.04 ± 0.24, EA: 1.56 ± 0.44, Control: 1.38 ± 0.35 ml/mmHg); thus, arterial stiffness was higher in the SA group. Plasma AOPP concentrations were higher in the SA group than in the EA group (SA: 31.7 ± 8.5, EA: 23.9 ± 6.9, Control: 27.2 ± 3.9 μmol/l). We found that plasma AOPP levels tended to be related to SAC ( P = 0.073, r = −0.31). Conclusions The present study provides a possibility that exercise training-induced oxidative stress may be partly involved in the mechanism underlying the adaptation of arterial stiffness in strength- and endurance-trained athletes.

Effects of Tennis Expertise and Type of Training Session on Dorsal and Lumbar Spine

Scoliosis has been found in up to 80% of athletes with an asymmetric load on the trunk and shoulders, such as javelin throwers and tennis players. Further research found asymmetry in volume between dominant and nondominant upper limbs larger in young tennis players than in control group. Anyway it is not clear the relationship between scoliosis and the practice of tennis. PURPOSE: To evaluate the dorsal and lumbar spine of expert and recreational tennis players before (Pre) and after (Post) two different types of training session. METHODS: The sample consisted of 17 tennis players (8 expert and 9 recreational male (age 21.2 ± 1.6 years). We assessed back surface by rasterstereography before and after two different training sessions both lasting 1 hour and half. The first one was a standard training session and the second was a specific over-shoulder shots training session., The following parameters were measured and recorded in Average 4D modality (longer interval of time, on 10 images): lordotic and kiphotic angle, length, imbalance and inclination for trunk, pelvic torsion, left and right lateral deviation, surface rotation. RESULTS: Tennis expertise had a significant main effect on surface rotation and right lateral deviation (P<0.05). Trunk length was affected both by type of training (P<0.05) and time (Pre vs Post) (P<0.05) while the interaction between tennis expertise (expert vs recreational) and time had an effect on trunk inclination (P<0.01). Left lateral deviation differed for type of training session (P<0.05). CONCLUSION: Expert tennis players had higher values on surface rotation and right lateral deviation, around or just above physiological values. Type of training significantly affected trunk length and left lateral deviation, indicating that over-shoulder shots lead to a higher stress for the spine.

Developmental Tendencies of Results in Female Heptathlon in the Olympic Games during the Years 1984-2008

The aim of this study is to assess a change tendency of the results in heptathlon and in particular events of this discipline. In the research the authors used results achieved in heptathlon in the Olym pic Games during the years 1984–2008. Top 20 female athletes of general standing were taken into consideration. MS Excel 2007 spreadsheet program and a method of document analysis were used to analyse and assess a change tendency. Mean values achieved in particular events showed that the highest results, which were above the average in each Olympic Games, occurred in 1992 and 2008. The levels of all mean values and final results in heptathlon were higher than average values described in the above mentioned years. Mean values did not show developing tendencies in the Olympic Games. A correlation analysis showed that 100 m hurdles, 200 m run and long jump had the biggest influence on the final result in heptathlon. The best results achieved in different events show a high sport level of these results which are close to results in individual competitions.Throwing events demonstrated the highest increasing tendency of results: javelin throw (10.84%) and shot put (8.02%); the smallest changes in the sport level were noticed in sprint events: 200m run (2.94%) and 100m hurdles (3.14%) and in high jump (3.89%). Big events such as the Olympic Games on the whole create favourable conditions for setting the world records, as is confirmed by the example of Jackie Joyner-Kersee with her result 7 291 points in Seoul Olympic Games.

우수 선수와 준우수 여자 창던지기 선수들의 운동학적 특성

본 연구의 목적은 여자 창던지기 선수를 대상으로 지지발 착지와 릴리즈 국면 시 우수 집단과 준우수 집단 간의 운동학적 차이를 규명하는데 있다. 이를 위해 국내 여자선수 8명을 대상으로 측정 최고기록이 45m이상인 선수를 우수 집단으로, 45m이하를 준우수 집단으로 구분하였다. 창의 투사속도에 있어서 릴리즈 단계의 수직속도는 집단 간에 통계적인 차이를 보이지 않았지만, 수평속도는 집단 간에 유의한 차이(p<05)가 있는 것으로 나타났고, 릴리즈 순간의 투사각에 있어서 우수 집단은 평균 36.3도를 보였고, 준우수 집단은 평균 42.3도를 보이면서 집단 간에 유의한 차이(p<.05)가 있는 것으로 나타났다. 지지다리 무릎각에 있어서는 힘 발 착지(우수>준우수)와 지지발 착지(우수<준우수) 그리고 완전착지(우수<준우수)에서 집단 간에 유의한 차이(p<.05)가 있는 것으로 나타났지만, 릴리즈 순간에 있어서는 유의한 차이를 보이지 않았다. 어깨각에 있어서도 힘 발 착지에서만 유의한 차이(p<.05)를 보였고, 릴리즈 단계에 있어서는 유의한 차이를 보이지 않았다. The purpose of this study was to investigate the kinematic parameters between a stalled group and a less skilled group of female javelin throwers, in order to record differences in their support landing and release phase. For this, the female athletes were divided into two groups: the sidled group, which consisted of javelin throwers with records over 45m, and the less skilled group, which consisted of javelin throwers with records below 45m. During the release phase, the horizontal velocity differed significantly(p<.05) between the two groups. The projection angle at the release moment also differed significantly(p<05) between the groups. The knee angle of the support leg differed significantly(p<.05) between the two groups at E1, E2, and E3, but there was no difference at E4. The shoulder angle differed significantly(p<.05) between the two groups only during the landing of the power leg.

Effects of off-season strength and plyometric training programmes on isokinetic strength and javelin throwing performance

A challenge created by the school environment is to develop a training programme for athletes with continuous progression in order to achieve improved performance. This lack of continuous progression leads to overtraining, overuse injuries, limited performance capabilities and ineffective maintenance of sport-specific seasonal programmes. As such, the aim of the study was to determine whether an off-season strength and plyometric training programme could enhance isokinetic strength and javelin throwing performance in high-school athletes. Twenty athletes, aged 16 to 19 years, who had at least one year of throwing technique training, were assigned to either a control group (n = 10) or a progressive, three-times a week, six-week training strength and plyometric training programme (n = 10). The best throwing performance from the previous season’s athletic competitions was recorded in metres (m) to the nearest 0.1 centimetres and compared to the best throwing performance recorded following the training programme. The results of the present study showed a significant (p strength, but also throwing performance in high-school athletes.

Mathematical Modeling and Numerical Simulations of Javelin Throw

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Is What You Think What You Get? Optimizing Mental Focus for Technical Performance

This article considers interesting differences between the mental focus employed by an elite athlete javelin thrower (E1) when contrasted with three international standard javelin throwers (I1, I2, I3). Athletes’ mental focus was recorded in both competition and training using self-report measures. In addition, kinematic analysis through point of release was examined for both categories of athlete. In both conditions, E1 demonstrated lower patterns of movement variability. Interestingly, a contrasting mental focus was recorded among athletes I1, I2, and I3 when compared with athlete E1. Tentative conclusions are drawn concerning the optimum sources of information for athletes before task execution in self-paced athletic events.

Updates on improvement of human athletic performance: focus on world records in athletics

Progression of world records (WRs) in athletics is a reliable mean to assess the potentiality of the human body, which also reflects how society has evolved over time and will continue to evolve. We conducted a quantitative analysis of WRs in measurable Olympic events from nine representative disciplines (100, 400, 1500, 10,000 m, marathon, long jump, high jump, shot put and javelin throw) in order to identify progression and trends. Data were gathered for the years 1900-2007 from the database of the International Olympic Committee. Overall, the relative improvement of athletic performance was higher in women than in men, being nearly doubled across the different specialities. The biggest increases were observed for javelin throw and shot put, in both men and women, respectively. Conversely, the improvement in race time was directly related to the race distance. We also observed a consistent significant linear model of WRs progression in time, although the improvement has substantially stopped or reached a plateau in several specialities. The observed trend might be explained by a variety of factors, including social and environmental changes, natural selection, advances in training and sport physiology, ergogenic aids and, possibly, doping. These results are discussed in a multifaceted approach, taking into account several biological, environmental and technological issues that might explain the trends observed.

Provisions and Credits of Horse riding in Islamic Doctrine.

Islam urges people to learn and practice horses riding became this type of sports is of a great importance in society due to the fact that it is the first weapon in both fighting and moving from one place to anther. The researcher mentioned a number of constraints and principles created by the speech of the prophet Mohammad (peace be upon him) and the successive influences of his companions, which is admitted by the legislator, makes practicing this type of sports allowed even if it is practiced for only amusement. The researcher uses the term "horse riding" to refer to shooting, dueling, and throwing the spear and the javelin which an only practiced by human being with some provisions because shooting is regarded as one of the most important means used in fighting during the old and modern ages. Dueling is also regarded as important means in jihad and self Defence because it requires, bodies of the individuals to be in a direct contact and this type of sport is organized by rules to be followed where, the sport of the spear and javelin, known nowadays as "javelin throwing" and "spear throwing" within the events that form the track and field games, these types of sports have their own provisions and credits. As for the games practiced by both human being and animals, they are the horse riding and camel riding. Human being interferes in competitions held among animals. Competitions held among animals are also organized by rules to be following but these types of sports are regarded as the most honorable ones because the prophet Mohammad (peace be upon him) practiced them and urged people to learn and practice them.

B15 やり投におけるやり加速メカニズムに関する動力学的分析 : 受動的関節トルクの機能とその発生要因(陸上競技)

B15 やり投におけるやり加速メカニズムに関する動力学的分析 : 受動的関節トルクの機能とその発生要因(陸上競技)

B14 やり投げ初心者におけるターボジャブを用いた投げ練習がやり投げに及ぼす効果(陸上競技)

B14 やり投げ初心者におけるターボジャブを用いた投げ練習がやり投げに及ぼす効果(陸上競技)

여자 창던지기 운동학적 요인의 일관성 평가

The purpose of this study was to investigate variability of kinematic factors affecting the record in women's javelin throwing. For this study, 8 female-javelin thrower participated in this experiment. The three digital video cameras (Sony, 120x) were used to record motions. Kwon3D 2.1 was used to process data and they were analyzed with Excell for factors. The sampling rate of a camera was 60Hz and shutter speed of a camera was 1/1000sec. The coordinate data were filtered using a fourth-order Butterworth low pass filtering with an estimated optimum cut-off frequency of 6Hz. The results were as follows: 1. From cross step to landing of delivery, the average velocities of CoM of non-dominant athletes were greater than dominant athletes and those of CoM of non-dominant athletes less than dominant athletes, but at release dominant athletes had a lower average velocity and a variability than non-dominant athletes. 2. From cross step to landing of delivery, the average throwing velocities and variabilities of a javelin of dominant athletes were greater than dominant athletes, but at release, dominant athletes had a higher velocity than dominant athletes and had a equal variability. 3. At every events, a forward or backward angles and variabilities of non-dominant athletes were greater than dominant athletes. 4. From cross step to landing of delivery, dominant athletes' elbow average angles were greater than non-dominant athletes and the variabilities of latter less than non-dominant athletes, but at release dominant athletes' variabilities were smaller than non-dominant athletes. 5. At landing of delivery, dominant athletes' knee average angles and variabilities of a supporting foot were a greater than non-dominant athletes, and at release, dominant athletes' knee average angles was a greater but variabilities less than non-dominant athletes. In conclusion, the dominant threw javelins fast while having stable postures and the range of elbow's angle large.

Field performance of javelin throwers: Relationship with isokinetic findings

. Published data related to javelin throwers remain poorly documented. The objectives of this study were therefore to compare isokinetic strength profile of the shoulder rotator muscles between javelin throwers and sedentary persons and to correlate isokinetic data with different field performance parameters. Eleven male javelin throwers and ten sedentary subjects participated in the study. Shoulder internal (IRs) and external rotators (ERs) were isokinetically assessed at 60, 240 and 400°/s in concentric and 60°/s in eccentric exertions. Subjects also performed throwing tests successively using a javelin and a ball (both of 800 g mass). Side to side comparison in the throwers group revealed a dominance effect in the concentric mode for the IRs at all speeds, and for the ERs at 240°/s. Sedentary subjects showed a dominance effect for the IRs at 60°/s and 240°/s. Simple isokinetic concentric-concentric ratios and mixed velocity DCRs (eccentric60/concentric240) of the dominant shoulder were significantly lower in comparison to the non-dominant side values, in the throwers population. Only the simple ratio at 400°/s and the mixed ratio were significantly lower in the sedentary subjects (dominant versus non dominant side). With respect to the dominant shoulder, no significant difference was noted between the groups the peak torque was bodyweight normalized. However, throwers showed a significant reduction of the DCR when compared to the control group. In addition, throwers exhibited moderate to strong correlations (0.61 ≤ r ≤ 0.89) between IRs and ERs strength and either the javelin throw test or the personal throwing record. For the sedentary subjects the javelin throw test was correlated only with the IRs concentric strength at 240°/s. In conclusion, javelin throwers showed a significantly reduced mixed ratio in comparison with a control group, even though body weight normalized peak torques did not differ between both populations. Significant correlation was established between rotator peak-torques and javelin throw test among the thrower athletes. Although training program in thrower athletes classically focuses on IRs strengthening, our findings strongly suggest the need for ERs performance improvement.

Transfer or specificity? An applied investigation into the relationship between fundamental overarm throwing and related sport skills

Background: Optimum sequencing of skills so that learners can benefit from the transfer of previous learning is an important issue in teaching and learning of motor skills. There is a lack of empirical evidence on the specificity and transfer of learning and its application to teaching/coaching situations. Purpose: To investigate the concepts of transfer and specificity in a practical physical education setting. The study examined the effects of two teaching intervention programmes on the performance and learning of the fundamental overarm throw, badminton overhead clear and javelin throw in a practical physical education setting. Participants and setting: Forty-six participants (27 males, 19 females; mean age 15.8 ± 0.60 years) from three secondary schools were assigned to one of three practice groups, i.e. the fundamental group, which practised the fundamental overarm throw; the badminton group, which practised the badminton overhead clear; and the control group, which did not practise but took part in normal physical education (PE) lessons. Intervention: The intervention programme consisted of six PE classes, and the skills taught were based on the practice groups. The control group carried on PE classes as normal, but no skills involving the overarm throwing action were taught. Research design: This study employed a repeated measures design involving three practice groups and three repeated measures (pre, post, retention). Performance scores for fundamental overarm throw, badminton overhead clear and javelin throw were measured. Data collection: Pre, post and retention tests were carried out on the fundamental overarm throw, badminton overhead clear and the javelin throw. All testing and teaching intervention classes were carried out in the participants' schools at scheduled physical education class time. Data analysis: Video tapes of all skill trials were analysed using qualitative analysis procedures. Data were statistically analysed to determine changes in skill performance between repeated measures. Findings: Results indicated that there was transfer from the fundamental overarm throw to the badminton overhead clear and the javelin throw (p < 0.05) but that there was no transfer from the badminton overhead clear to the javelin throw. The results indicate that participants in the fundamental throw teaching programme showed significant learning effects not only in the fundamental overarm throw but also in the specific sport skills of the badminton overhead clear and the javelin throw. Conclusions: The results support the notion of transfer between fundamental motor skills and sport specific skills. This has practical implications for the teaching of physical education.

Skill Level and Gender Differences In Release Phase Durations In The Javelin Throw

The javelin throw requires the creation of a large amount of momentum during the runup to then transfer to the javelin at release. A fast momentum transfer phase is thought to be most effective. PURPOSE: To determine if there are timing differences in the final phases of the javelin throw release related to gender or skill level. METHODS: Male and female finalists in the 2004 USATF National Championships and the 2004 Olympic Games were filmed. The final release phase consists of a cross-over step onto the right foot (RTD), then left foot plant (LTD) and javelin release (REL). The instants of RTD, LTD and REL were estimated within 0.1 frame for the two best throws for each athlete. The time period between RTD and LTD the thrower is in single-support (SS) while the time between LTD and REL, the thrower is typically in double-support (DS). The phase times were compared between skill levels for each gender with the hypothesis that the more skilled the group, the shorter the duration for each time phase. Pearson correlation coefficients between throw distances and time durations were computed. RESULTS: For both genders, the more skilled athletes had shorter times. There was only a statistical difference in the DS and Total times between the two men's groups (p = 0.01 and p = 0.006, respectively). The only statistically significant relationships found were between the throw distance and the DS and between the throw distance and the Total times (p = 0.03 and p = 0.007, respectively) for the combined male data. These relationships were not particularly physically meaningful due to their small values (r = −0.31 and r =−0.38, respectively).Table 1: Mean (s.d.) distance (m) and time (s)CONCLUSION: This data suggests that while timing may be important, there are more important factors that influence the throw distance.

B7 ジャベリックスローにおけるターボジャブの投射初期条件に関する研究(運動のダイナミクス)

The "turbo-jav" is used in the javelic throw as an introduction to the javelin throw or as a technical tool with which to practice the javelin throw. The present study investigated the flight characteristics of the turbo-jav. The javelic throws of 50 junior high school and university students were measured. Each thrower was videotaped using two high-speed video cameras during while throwing the turbo-jav. Each condition of release of the turbo-jav was measured using the 3-dimensional DLT method. The results revealed a significant positive correlation between initial velocity and throwing distance in the javelic throw. A comparison of turbo-jav and javelin throws indicated that the throwing distance was not small even when the angle of attack is large. When the turbo-jav is thrown, the actual throwing distance is smaller than the theoretical throwing distance without air. In other words, the flight characteristics indicate that the flight of the turbo-jav in the javelic throw differs from that of a thrown javelin.