情報技術とりわけAI やロボットなどの進化は人間の能力を上回るほど一部の分野では目覚ましい．このような進化がすすめば，生産性が向上し，人間が必要最低限な生活をするためのコストは小さくなり，社会が大きな影響を受け変容することが考えられる．想定される変容した社会では最低限の生活は可能となるため，外発的動機づけは低下し，内発的動機づけの重要度が向上すると考えられる．本研究では，「2021 年東京五輪」開催前の時期におけるランニングと卓球を対象とし，内発的動機づけを構成する自律性の外部環境依存に関する調査を実施した．

The purpose of this research was to clarify the “technical training” activity actually employed by table tennis players, targeting world’s top-level women choppers. A survey was conducted using a semi-structured interview based on qualitative research focusing on the process by which players strengthened their skill. The subjects were 7 women choppers who were ranked within the world top 50 by the International Table Tennis Federation in February 2017. The results indicated that all of them had gone through a process in which, after they had become choppers, they made efforts to acquire “cut and push” skill at the first stage, after which there was a period of transformation in their style of play to one of attack. Finally, they made efforts to explore original playing techniques by confronting problems with their individual style. With regard to their current approach to individual problems, the following aspects were emphasized: 1. The importance of the early stage of a rally, from the serve to the 3rd or 4th ball; 2. The importance of a long rally, i.e. being able to hold out tenaciously; 3. The importance of an attack technique without a fixed idea, which is an approach hardly adopted by choppers; and 4. A playing style that considers players’ tasks and aptitudes, to make full use of reflections from games. Clarification of the overall picture of the strengthening process of top players may make it possible to devise individual training concepts by imaging their futures, suggesting the need to propose a new training activity.

 This study conducted interviews on two world top level women choppers in table tennis, and by asking them when and why they started playing table tennis and changed their play styles to choppers, and how, afterwards, reached to the top level of the world, it aimed to reveal the factors of the growth process required to become top players.

 From the talks of two players, following points are considered to be important in the process to become the world-level choppers. Even if the start age is slightly late in the table tennis, there is a possibility of reaching the top level, being interested in chop plays, it is easier to success if choppers take measures to their opponents because measures are not easy to be taken in younger ages, physical training are effective to obtain the maintaining prerequisite physical conditions to acquire new sense of movement and interest, and practicing with stronger players than their own.

In this study, author A, a former table tennis chopper who competed at world level, made a reflective analysis of his practical experience to clarify the kinaesthetic ability of situational feeling of the chop techniques with strong backspin in table tennis.

Consequently, it was found that there are two situations in which a strong backspin chop is the best option: “a situation in which the ball is returned easily using a strong backspin chop” and “a situation in which the opponent does not expect a strong backspin chop”.

We also clarified the points for judging such situations. In addition, the effectiveness of these two situations was demonstrated by the author’s own actual play. At first glance, these findings may seem like a statement of the obvious. However, in coaching, it is not often seen that aggressive chop techniques are actively taught to choppers. Therefore, elucidation of the circumstances of the aggressive chop as described above is extremely important and will provide many suggestions for reviewing future chopper training policies.

The purpose of this study was to clarify perspectives of teaching and evaluating table tennis services: how to display a player’s movement to his/her opponent. This study was done as a part of a 5-year period of competition support using sport sciences.

The main results and findings were as follows:

1) In table tennis service, when serving a ball far from or near to the net on the receiver’s court, there was often a difference in the first bound placement on the server’s court and the height of the ball-hitting position. Furthermore, when serving a ball to the right or left of the receiver’s court, the direction of the server’s trunk often differed between the courses. These were considered important perspectives for teaching and evaluating table tennis service of top Japanese junior players.

2) The check sheet made in this study to improve the similarity of service movement between different kinds of services was effective for top Japanese junior table tennis players, even for first-time participants. Future subjects of this check sheet would expand to include other coaches and players of varying competitive levels.

3) A comparison between the check sheet of table tennis service movement and table tennis textbooks indicated that the check sheet gave new practicable insights into coaching for improving service: how to display a player’s movement to his/her opponent.

In this study, the author with remarkable achievements in table tennis as a world-leading chopper aimed to reflect on and analyze her directional quality toward kinaestic senses regarding her strong topspin long service, in order to reveal a kinaestic ability, an intuitive one in particular, for acquiring the skills for the said service. Accordingly, as the essential structure of an intuitive kinaestic ability for effectively using a topspin long service, the meaning of “outsmarting the opponent” was highlighted. In addition, the suggested conclusion was that the said service would produce effects in specific situations such as “when the opponent gets used to backspin techniques”, “when the opponent are distracted by backspin techniques” and “when the opponent has lost her judgement due to fatigue”. It is true that this conclusion was drawn from the personal experiences of the author, but it was her practical knowledge accumulated in the matches throughout her life as a competitive table tennis player where it was frequently tested and validated as well as experiencing many successes and failures. The author thinks that her having been able to make this conclusion can contribute to the future development of table tennis coaching.

    This article aims to find a clue to developmental processes of techniques by reviewing the transition of game rules in the racket type sports and the terminology items related to techniques described in the literature. The results will be summarized as follows.
1. A general rule of the modern tennis, consisting of a total of 35 articles, was adopted in 1923. For around 90 years after the establishment, it is considered as the major changes; both legs can be away from the ground in the case of service, and “tie- break” was introduced.
2. In 1922, the basic rule of modern table tennis was enacted in England. In 1931, the international competition rules, including 47 articles, were established. Then, more than ten-time revisions on the rules could be made from 1937 to 2014.
3. The fundamental rules of the modern badminton competition were established by “Laws of Badminton,” issued in 1934. The rules made a major change; “rally point system” was replaced with “a side-out system” in 2006, and 21 points in three games matches could be applied in all games.
4. In technical terms of tennis, “volley” was shown in all references. The technical term of table tennis, “drive,” was included in 82％ of references. With regard to badminton, “smash” was presented in all references. Badminton has the most technical terms about service, stroke, and shot.
5. Figure 4 shows the developmental process model (hypothesis) of the techniques of racket type sports.