Teaching balance for judo practitioners

Judoka’s balance consists in passing from an individual balance to an interdependent balance. The aim of this work is to study the mechanisms of imbalance and the mechanisms of postural regulation in judoka in order to deduce some considerations for teaching. The first part describes in the notion of imbalance in judoka. This is fundamental for technical learning. The objective analysis of postural control requires kinetic and kinematic measures. The second part relates how different scientific works were conducted in an attempt to understand the postural control in judoka. The role of the grip (kumi-kata) is presented in the postural regulation in judoka, the postural adaptations induced by judo training and the intrinsic postural factors of judoka that influence the direction of his falls. The various quoted pieces of information are illustrated with practical examples. The role of the grip (kumi-kata) is fundamental for the judoka because – it provides somaesthetic information about his own movements and positions as well as those of his opponent, – it also enables controlling, attacking and defending forces to be applied against the opponent as well as control of the judoka’s own balance. On the basis of this, the authors make various proposals for training in order to improve the efficiency of the postural activities of judoka. © Idōkan Poland Association “IDO MOVEMENT FOR CULTURE. Journal of Martial Arts Anthropology”, Vol. 11, no. 1 (2011) pp. 42–46 The mechanisms for balance are dependent on control of the posture in such a way that the vertical axis of gravity remains within the support surface (the support polygon). The movement of a single body part alters the position of the body’s centre of gravity and the slightest body part movement is therefore a source of imbalance. In judo, the two opponents are balanced together by means of their grip (kumi-kata). A judoka’s postural control is based on numerous complex factors because, apart from his own movements and actions, there is a wide range of external forces exerted by his opponent that constantly attempt to upset his balance. According to Cadières and Trilles [1998], the judoka not only alters his posture with reference to the vertical axis but also in respect of the forces applied against him by the opponent. One study has shown that the posture of the judoka influences the likelihood of his falling in a particular direction [Paillard et al. 2005]. Furthermore, the role of the grip (kumi-kata) is fundamental for the judoka because it provides somaesthetic information about his own movements and positions as well as those of his opponent (e.g. his opponent’s movements and positions) and it also enables controlling, attacking and defending forces to be applied against the opponent as well as control of the judoka’s own balance [Paillard et al. 2005]. Furthermore, the motor activity of the judoka is very specific and results in particular postural adaptations to the movements that are practised by preference [Paillard et al. 2007]. The purpose of this study is to examine in detail the three issues referred to above: 1. The influence of posture on the direction of fall, 2. The role of kumi-kata, 3. Postural adaptations resulting from practice, and then, on the basis of the outcome of the examination of these three issues, to make various proposals for training. 1. The influence of posture on the direction of a judoka’s fall In an experiment carried out with judoka experts, Paillard et al. [2005] considered whether it was possible that the postural positions of a subject, Th is co py fo r p er so na l u se on ly – d ist rib ut io n pr oh ib ite d Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d — Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d Electronic PDF security by Committe of Scientific Research, Stowarzyszenie Idokan Polska Poland Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d — Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d 43 E. Margnes, T. Paillard — Teaching balance for judo practitioners evaluated on a force platform in relation to the anteroposterior axis, in a bipedal condition and without an opponent, could influence the direction of falls (forwards or backwards) in combat situations. In other words, a hypothesis might be made that judokas with a forward centre of pressure (CP) might be predisposed to fall forwards more often. However, the analysis of the results produced the opposite conclusion. The average position of the CP of pressure of subjects who are “forward fallers” is, in fact, situated more in a backward position. The forward faller, in a situation of precarious balance which could be broken by imbalance to the rear, will be likely to react by a reflex movement which involves pushing the arm against the opponent, which can be exploited in turn by a forwardthrowing attack. 1.1. Practical aspects Action-reaction attacks (causing the opponent to make forward-backward or backward-forward movements) using attack sequences or feigning attacks would have the advantage of upsetting the opponent’s balance and causing him to fall. That is to say that a backward-forward movement would be particularly effective against an opponent with a CP positioned towards the rear. 1.2. Proposals for judo training It is advisable therefore to make the judoka aware of his own predispositions in respect of his vulnerability either to forward-backward movements or to backward-forward movements. Different training exercises, working especially on action-reaction attacks, can be used to work on balance disturbance. For example, uchi komi or nage komi can be used to produce a feigned attack on the rear in order to then attack the front. However, using the same training exercises or in pre-arranged combat (Yaku soku geiko, kakari geiko), random forms of attack should still be used. Thus, uke must never know in advance if an attack is going to be made in the form of a direct attack or an action-reaction attack. This point is paramount to ensure that the opponent’s actions are not over-anticipated and, especially, to ensure that he is aware of the postural adjustments that have been made. Here, it is necessary to be very attentive to the slightest body part movements that need to be made when in a difficult postural position in order to maintain postural control. The judoka must therefore learn to auto-regulate himself and be conscious of the reactions in his chest, arms and legs, according to the particular attack made against him. He must also learn to take advantage of precise feedback from his partner or trainer. 2. Interdependent balance in judo – the key role of kumi-kata In judo, the two opponents are balanced together by means of their grip (kumi-kata).This grip can be such that on occasions the projected centre of gravity of one or even both combatants is situated outside their own support polygon. The kumi-kata of the judoka provides somaesthetic information about his own movements and positions as well as those of his opponent (e.g. his opponent’s movements and positions) but it also enables controlling, attacking and defending forces to be applied against the opponent as well as control of the judoka’s own postural balance. The judoka’s postural regulation results (apart from visual and vestibular information), from proprioceptive and cutaneous information, which originates from four additional sources two hand supports and two supports from the soles of the feet. The sensory receptors of the first three cervical vertebrae transmit proprioceptive information that is useful for the judoka’s process of postural regulation. 2.1. Practical aspects It is difficult for the judoka, especially the beginner, to discern the relevant information that will enable him to maintain his postural stability. In a combat situation it is advisable to avoid a kumi-kata from above (a hold behind the head which blocks the head and pushes it downwards). Apart from limiting the judoka technically and tactically, this disturbs the process of obtaining proprioceptive information and impedes the visual field. It is also important to teach the beginner how to carry out the “traditional” grip (one hand on the elbow and the other at the back and bottom of the neck), which enables him to use all the receptors that can detect any possible error. This grip with its potential follow-up actions (using traction, pushing and compressions forces) is also a source of imbalance because it frequently changes in direction and intensity simultaneously as a result of offensive or defensive tactics. In relation to this last point, it is proposed that a beginner judoka must establish new balance references and new sensorimotor skills in order to learn to balance while carrying out pushing or traction forces with the use of his upper limbs, through the use of compensatory movements of the chest or anticipatory or compensatory movements Th is co py fo r p er so na l u se on ly – d ist rib ut io n pr oh ib ite d Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d — Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d Electronic PDF security by Committe of Scientific Research, Stowarzyszenie Idokan Polska Poland Th is co py fo r p er so na l u se on ly – d ist rib ut io n pr oh ib ite d Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d — Th is co py fo r p er so na l u se o nl y – di st ri bu tio n pr oh ib ite d Electronic PDF security by Committe of Scientific Research, Stowarzyszenie Idokan Polska Poland 44 “IDO MOVEMENT FOR CULTURE. Journal of Martial Arts Anthropology”, Vol. 11, no. 1 (2011) of the lower limbs. The positioning of the hands on the judoka opponent, as well as the positioning of the forearms or trunk on the opponent’s trunk also provides potential additional supports for balancing or