3/26/2008

A Comparative Study of Throwing Speed

A COMPARATIVE STUDY OF THROWING SPEED BETWEEN HEAVIER AND LIGHTER CATEGORIES IN JUDO.

Ramdane Almansba - r.almansba@yahoo.fr
Laboratory of Sport and Health, Faculty of Sciences Sport and Physical Education, France.



The aim of this work was to verify if there was a difference in throwing speed performance between heavier and lighter weight categories in judo. Sixteen judoists aged 18±3 years-old, eight considered in the light weight category (-73 kg) and eight considered in the heavy weight category (+73 kg) participated in the study. A force/velocity test was used to determine the anaerobic power, strength, and pedal speed for each subject. Three trials of Nage-komi exercise, each comprised of 15s sets of Osoto-gari, Uchi-mata and Ippon-seoi-nage throws were performed by each subject to ascertain throwing speed. Throws within the sets were intersected by one period of 3 minute passive rest while the trials were separated by one period of 10 minute passive rest. Heart rate and the greatest number of throws within each set were measured for three trials.
We used an ANOVA to compare the number of throws between the two weight categories and a "Student" test when the difference was significant. A correlation was used to examine the link between the different parameters.
Results show that in the force/velocity test pedal speed did not differ between the two categories. However, there was a significant difference between the two categories when throwing speed was measured by the number of throws executed during the Ippon-seoi-nage and Uchi-mata, but there was no significant difference between the two categories for Osoto-gari.

Our study showed that the throwing speed of judoists represented by number of throws appears to be significantly different between the two categories. The lighter category has more speed than the heavier category using arm technique (Ippon-seoi-nage), while the heavier category has more speed using leg technique with half turn of the attacker's body (Uchi-mata). As a result, throwing speed is related to the type of technique used and not weight category.



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3/06/2008

Effects of Judo Kata Practice on Cardiorespiratory Health

EFFECTS OF RECREATIONAL AND COMPETITIVE JUDO KATA PRACTICE ON CARDIORESPIRATORY HEALTH AS EVALUATED BY A PORTABLE GAS ANALYZER SYSTEM. A PILOT STUDY

Carl De Crée, prof.cdcree@earthlink.net , IGER

The last couple of years there is an increased interest in judo kata practice, triggered by the introduction of kata contests at an international level. Various physiological and psychological scientific studies have focused on karate kata, but virtually no addition has been paid by the medical literature to the cardiopulmonary or other effects or requirements of judo kata practice. The purpose of this study was: (1)to gain initial cardiorespiratory data in both recreational and competitive judo kata players, and (2) to test the suitability of the Jaeger Oxycon Mobile™ portable gas analyzer system in similar studies. Twentyfour male subjects participated in this tests. Judo kata are standardized formal choreographic exercises, of which commonly 7 different exercises are practiced, usually in couple. Sei-ryoku zen’yo kokumin taiiku was not included because of its various solo components. Each kata was tested, though not all subjects were able to perform all kata given the highly advanced level required to suitably perform the two ultimate kata. Cardiorespiratory data were obtained by using a Jaeger Oxycon Mobile™ portable gas analyzer system, while blood lactate was determined by use of a portable lactate analyzer. Results showed that kata practice is an excellent aerobic exercise, of which the low injury component makes it suitable for judo practitioners of all ages. Considerable differences in energy expenditure exist between performers despite the standardization. We suggest that the level of experience as well as self-determined pace,intensity and type of kata are responsible for these results. Portable gas and lactate analyzers are suitable instruments to study the cardiorespiratory needs of judo kata practice.

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