1 Introduction
The hammer throw event is one of the most attractive and complicated of the track and field events. The sources of modern hammer throwing are hidden in the distant past as combination of work, leisure and warfare. During the 18th and 19th centuries in Ireland and Scotland, where the ancient traditions live, throwing hammer was the sport of farmers and workers. Outstanding rulers and politicians of the middle ages were given partly derived from their throwing abilities. Eadweard Muybridge did probably the first movement study by sequence photographs of hammer throw. Athletes with an Irish background advanced the world record 33 times from 1877 until 1937 and won gold medals at five Olympic Games. The rules of the implements in modern competitive hammer throwing were laid down in 1887 in the USA (Bartonietz, 2000).
Throwing hammer event is historic event for men, while the men have been throwing the hammer for centuries and last world record was before 26 year, unlike women who have a relatively short history in the event. Wagner (2006) noticed that women‘s hammer throwing was not ratified until 1995, however being recognized in several countries prior to its ratification. Several women began to throw the hammer in the 1980s, like Cheryn Ison, who threw over 42 m in NS. Women‘s hammer throw was added to the World Championships in 1999. The record has grown rapidly behind the 70 meter mark, in spite of the event‘s short history. Several elites such Olga Kuzenkova (RUS), Mihaela Melinte (ROM), were the early pioneers of the sport, they set the first 14 world records (Kuzenkova 6, Melinte 8).
Recently since 2009, Betty Heidler (GER) and Anita Wlodarczyk (POL) lead the women record. In the last 12 years the world record is broken 7 times (see table 1) even in 2006 it had been broken 3 times. It refers that the women still have more to show in the future.
For the previous reason the studies are still focusing on men‘s hammer throwers, except some publications which focused mainly on women‘s technique and studying the difference between men and women in hammer throw, which due the differences to morphological differences and implement‘s weight and length. They may be try to find a way for further progress and a new world record after 26 years. Riley et al. (2005) referred, from their point of view, to the lack of research which hinders evolution of hammer, they illustrated the efforts of researcher specially Jesus Dapena, who began a set of biomechanical publications that served understanding technique and going further with the kinetics of throwing hammer and his publications are considered educational at the same time. Most of researches are considered as diagnostic studies and added something valuable to the literature. In my opinion the lack was in the kinetically studies except few of them. Henceforth the researches started to go towards the kinetically diagnostic studies for the source of the forces trying to reexamine some parameters or trying to develop the technique or the physical requirements to serve the performance. Since the common and popular attitude to find the reason of lack performance is to quantify the hammer head,
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thrower center of mass and the common center of mass parameters. Tthe current study is then a piece of the hammer throw knowledge puzzle biomechanical picture by studying the kinetic energy of hammer head and the first piece of quantifying the body segments movement of hammer thrower.
Table 1. Women Hammer Throw world record progress Year World Record
(m) Record Holder Placement at Oympic Games and distance(m)
1st 2nd 3rd
1997 73.1 Olga Kuzenkova (RUS) 1998 73.8 Olga Kuzenkova (RUS) 1999 76.07 Mihaela Melinte (ROM)
2000 75.68 Olga Kuzenkova (RUS) 71.16
Kamila Skolimowska 69.77
Olga Kuzenkuva 69.28 Kirsten Münchow 2001 73.62 Olga Kuzenkova (RUS)
2002 73.07 Olga Kuzenkova (RUS) 2003 75.14 Yipsi Moreno (CUB) 2005 77.06 Tatyana Lysenko (RUS)
2006 77.26 Gulfiya Khanafeyeva (RUS)
2006 77.41
77.8 Tatyana Lysenko (RUS) 2007 77.3 Tatyana Lysenko (RUS)
2008 77.32 Aksana Miankova (BLR) 76.34
Aksana Miankova 75.20
Yipsi Moreno 74.32
Wenxiu Zhang 2009 77.96 Anita Wlodarczyk (POL)
2010 78.30 Anita Wlodarczyk (POL) 2011 79.42 Betty Heidler (GER) The data taken from: Bartonietz 2000,
http//www.iaaf.org/statistics/toplists/inout=o/age=n/season=0/sex=W/all=y/legal=A/disc=HT/detail.html, http://www.iaaf.org/statistics/records/inout=o/discType=5/disc=HT/detail.html
http//berlin.iaaf.org/results/racedate=082009/sex=W/discCode=HT/combCode=hash/roundCode=f/results.html#detW_HT_ha sh_f
Kinetic energy is the combination of the effect of the velocity and the mass, since the velocity and acceleration of hammer head was killed in search, but the effect of body mass on performance is still in search process. The combination between the velocity of each body segment and their masses may be another addition to the anthropometrical characteristics of throwers, as well as the contribution of each segment in the output energy that is presented in hammer head.
Every result needs approach method, it is useful to reexamine the biomechanical parameters, in order to see the progress of technique and try to track the change in the performance, using new
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measurement methods and technology or employ new physical theories. But it depends also on the researcher target. Most of studies targeted to describe the best performance, which could be possible not found but in competitions, especially international competitions and Olympic Games, where the motivation and thrower high form are found. On the other hand, some difficulties are found which may be affecting the result accuracy. They illustrated as following
No chance of mounting body land markers.
Few cameras may be 2 or 3
The cameras are put from the circle center between 15 to 70m away.
Recording the movies is from behind the nets. Therefore, the used cameras have to be very special and powerful lenses focal length and resolution.
The studies, which targeted to more accuracy and experimenting or testing measurement systems like the force plate form for example, have to come over the previous factors. Therefore the solution was to record the material during training session or even in a separate session, even they lose the chance to gain top performance and may be a new world record. But it can also be not bad if the participant is top elite hammer throwers, which means a stable performance, in addition choosing the good training season like pre competition season for example.
The next level is to think how to feed the coach/thrower back as fast as possible with the performance. To have the opportunity to correct the faults and improve the performance based on a quantified data not just experts eye, although it is very important.
Agostini et al. (2003), Murofushi et al. (2005), Ohta et al. (2008), and Brice et al. (2008) worked on this idea , which is how to develop a measurement system of hammer throw to give the immediate feed-back as possible while the throw is still fresh in the thrower head during training session. They used the technology starting from recording wind acoustic to reach using wireless and Microelectromechanical systems (MEMS) technology. Who know about the hammer, realize how it is difficult to use measuring systems else but wireless or portable systems for direct result output.
Unfortunately, none of those systems were offered commercially, thus, it was necessary to manufacture the developed system first and test its validity. Therefore, the second part of the current is a developed system for measuring the 3D acceleration and 3D angular velocity as well as the strain force in the wire.
During meeting coaches and some researcher in Germany, I found that no one knows about the previous versions of hammer measurement systems.
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1.1 Objectives of the study
The purpose of the current study is to answer the following questions
1. What is the character of body kinetic energy, hammer head kinetic energy and body segments kinetic energy of throwing hammer during turns and release phase?
2. What is the sequence of transferring kinetic energy of body segments during turns?
3. What is the relationship between the body segments kinetic energies and both of total body kinetic energy and hammer head kinetic energy during turns and release?
4. Could we find out a specific set of body segments that interact to achieve a better distance?
5. Could we determine the transfered kinetic energy during release phase?
6. Is the measurement system valid to be used as a feed-back system for hammer thrower?
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