テニスのサービスは試合を優位に進めるために重要だが，苦手意識のあるコースでは，その精度が低下する傾向にある．本研究では，この原因がサービス時の注意の向け方 (身体運動か身体運動以外か) に起因するか，また，身体運動以外への注意を促す教示が，サービス精度低下の予防に有効かを検討した．参加者は，大学男子テニス選手9名とした．実験課題は，得意・苦手コースを狙った第1サービスとし，何も教示しない「教示無し条件」，3打先までのプレーを予測させる「予測条件」の2条件で行わせた．結果として，苦手コースのサービスで，参加者が過度に身体運動に注意を向けるという現象は見られなかった．これは，苦手コースの精度低下は，注意の観点から説明できないことを示す．一方，予測条件では，球の回転数および正確性が有意に向上した．このことは，試合展開の予測がサービス・パフォーマンス向上に有効である可能性を示唆するが，その効果は，教示無し条件で身体運動以外に注意を向けている選手に限定された．つまり，サービス時にゲーム展開を予測することは，サービス精度の向上に有益ではあるが，選手の特性に合わせて利用することが望ましいと考えられる．

Influences of predicting the development of the game on the accuracy of serves in tennis
In tennis, a good serve is important for dominating in games, but the accuracy of serves tends to decrease after a bad serve in which the ball ends up in an area other than where the server intended. The present study examined whether this decrease is caused by servers’ attention to their movements or other factors, and whether advising them to attend to something other than their own movements would be an effective way to prevent the decrease in the accuracy of serves. The participants were 9 university male tennis players. The study focused on the first serve, targeting both good and bad serves under two conditions: (a) a no-advice condition, in which no advice was given to the players, and (b) a prediction condition, in which the players predicted where the ball would land on the next 3 serves. The results indicated that when the players made a bad serve, there was no tendency for them not to attend to their movements. This suggests that the decrease in accuracy of serves after a poor serve is not caused by a lack of attention. On the other hand, in the prediction condition, ball spin and the accuracy of serves significantly increased. This suggests that having players predict the game development may be an effective way to improve their serves. However, this effect was found only in those players who had attended to something other than their movements in the no-advice condition. That implies that although predicting the game development when serving may be effective for improving the accuracy of serves, the effectiveness of this method will depend on each player’s character.

本研究は，ストレートのリリース速度と回転速度が大きくコントロールが不安定な左投げ大学生投手を対象に，コントロール改善のコツをつかんだ過程と奪三振率増加と与四死球率減少のメカニズムを明らかにすることを目的とした事例研究である．方法は，コントロールが不安定な原因を投球腕の遅れとトップポジションの不安定さと見立て，改善策を定性的・定量的に検証した．結果，投げ始めに両手と踏み込み足を高く挙上する動作が，投球腕の遅れを緩和しトップポジションの安定化を，握り方の変更がスライダーの安定化をもたらし，それがストライクゾーンの著しい逸脱を減少させ，コントロールの不安解消が強い腕の振りにつながり，奪三振率の増加と与四死球率の減少に帰結したメカニズムが示唆された．変更の契機はいずれも近距離でのキャッチボールであった．投球動作という暗黙知を理解させるために用いたメタファーを，対象とした投手が咀嚼して感性と調和させたことがコツの獲得につながったことが推察された．

The mechanism for improving baseball pitch control and performance: A case study of a college baseball pitcher who threw high-speed fastballs with high spin rate at release but had trouble with location
The subject of this case study was a left-handed college baseball pitcher who could throw high-speed fastballs with high spin rate at release, but had trouble with location. Our aim was to clarify the process by which he learned to improve pitch control, and the mechanisms for increasing strikeout rate and reducing base-on-balls and hit-by-pitch rates. Our findings show that raising both hands and holding the front foot high at the start of the pitch stabilized the top positions. The slider was stabilized by changing the grip. It was suggested that those changes resulted in a reduction of instances of significant deviation from the strike zone. Reduced anxiety about control led to stronger arm movements, which in turn increased the strikeout rate and reduced base-on-balls and hit-by-pitch rates. Playing catch at close range affected those changes. Our findings suggest that the pitcher assimilated the metaphors used for developing a tacit knowledge of pitching motions, and harmonized those with his sensitivity, resulting in his acquisition of the mechanism for improving pitching performance.

本研究は，バドミントンのスマッシュをトレーニングすることが，投球速度および動作に与える影響を実証的に検証することを目的とした．対象者は右投げの大学野球選手2名であった．トレーニングの内容は，10ｍ離れた目標に向けてトスされたシャトルをスマッシュすることとし，20回×5セットを週に4日行ってもらった．測定はトレーニングの開始前（Pre），開始1週間後（Post1），終了後（Post2）の計3回行った．その際，投球速度および動作を測定し，経時的変化を比較した．その結果トレーニング開始前と比較して，トレーニング後は両対象者とも投球速度が有意に増大した（対象者A; +9.4km/h, 対象者B; +13.6km/h)．また，両対象者とも投球腕各部位の速度が変化した．さらに投球腕各部位の獲得速度が増大し，特に手部の最大速度が増大した．これには，力学的に効率的な投球を行うための近位部から遠位部への運動の順序性，いわゆる“運動連鎖”の改善が達成されたためと考えられる．したがって，バドミントンのスマッシュをトレーニングすることは，投球腕の運動連鎖の効率化に有効である可能性が示され，その結果，投球速度の増大に効果があると考えられる．

Influences of badminton smash training on the ball velocity and throwing motions of two baseball players
The present study examined effects of having baseball players practice badminton smash training on the players’ ball velocity and throwing motions. The participants were two right-handed college baseball players. In the training, they smashed a tossed shuttle, aiming at a target 10 meters away, 20 times per set, 5 sets a day, 4 days a week. Their ball velocity and ball velocity were measured 3 times: before the start of training (Pre), after one week of training (Post 1), and after the completion of training (Post 2). The results indicated that the pitching speed of both players increased significantly after training (participant A: +9.4 km/h, participant B: +13.6 km/h). Additionally, the speed and acceleration of the players’ throwing arms increased; in particular, their maximum hand speed increased. This may have been due to an improvement in “kinetic chain”, that is, that order of movement from proximal to distal, resulting in a throwing motion that was more efficient mechanically. This suggests that badminton smash training may improve the motion of baseball players throwing arm effectively, thus increasing ball velocity.

本研究は，野球における打者の一塁ベ−スへの走塁において駆け抜ける動作とヘッドスライディング動作タイムの比較を行い，一塁への走法について検討した．大学野球部の選手13名を被験者とし，ホ−ムから一塁ベ−スまで疾走させた．一塁ベ−スを駆け抜ける動作と一塁ベ−スでヘッドスライディングを行う動作を3回ずつ行わせた．一塁ベ−ス手前7ｍの位置から一塁ベ−スまでの動作をハイスピ−ドカメラで撮影し，画像からランニングタイムを算出した．大学野球チ−ムの54名を対象にヘッドスラディングについてアンケ−トを実施した．ヘッドスライディング動作タイムが駆け抜ける動作タイムより有意に短い値を示した（p < 0.05）．ヘッドスライディング動作タイムが駆け抜け動作タイムよりも短い者ほど，一塁ベ−ス近くに手を付いていることが明らかとなった．また野球選手54名を対象としたアンケ−トで40％の選手がヘッドスラディング動作で手などに受傷したと回答した．本研究結果は，ヘッドスライディング動作を行うと駆け抜け動作よりも速くなる可能性を示したが，ヘッドスライディング動作を習得することで機動力ある野球を展開できる可能性があると考える．

Styles of running to first base in baseball: comparison of the run-through and diving styles
The present study examined the styles of running to first base that baseball players have been taught to use. The times taken by batters using a run-through style and a diving style were compared. The participants, twelve members of a university male baseball club, were instructed to run at full speed from home plate to first base using the run-through and diving styles, three times each. Their runs were filmed with a high-speed camera from a position 7 m in front of first base, and their running times were calculated from the films. In addition, a questionnaire about the diving style was completed by 54 members of the baseball team. The running times using the diving style were significantly shorter than when the run-through style was used (p<0.05). The data also revealed that the participants whose diving style running times were shorter than their run-through times were diving with their hands near first base. On the questionnaires, 40% of the players on the team responded that they had experienced injuries, such as to their hands, when they had used the diving style. The results of this study suggest that the diving style may be faster than the run-through style, but if players are trained in the diving style, their baseball playing may become more maneuverable.

本研究は，大学体育バドミントン授業受講者における競技経験と技能レベルとの関係性を明らかにすることを目的とした．対象者はC大学及びD大学でバドミントン授業を履修した148名であり，バドミントンの技能と相関が高いとされるフォアハンドによるロングサービスを試技させた．飛距離ごとに得点を付与し，その得点をもとに技能レベルを3群に分類した上で，これまでの競技経験との関係について検討した．その結果，中学校期高校期ともに，上級群ではバドミントン経験者と打具操作種目が，初級群では運動部経験なしが有意に多かった（p＜0.01）．この結果から，バドミントンを含め打具操作種目を経験していない学習者には，打具の操作が大きな課題となり得ることが明らかとなった．

Relationships between competitive sports experience and skill level of students enrolled in university physical education badminton courses
The present study aimed to clarify relationships between competitive sports experience and the skill level of students in university physical education badminton classes. The participants were 148 students who were enrolled in badminton classes at Universities C and D. Each participant’s badminton skill was rated as high, medium, or low, based on the participant’s forehand long serve score, which is a measure of badminton skill. Their previous sports experience was then compared to their badminton skill level. Those with a high level of skill at badminton were significantly more likely to have participated in badminton or another sport involving a hitting motion during their middle or high school years, whereas those with a low level of skill in badminton were significantly less likely to have had experience engaging in sports during their middle or high school years (p<0.01). These results suggest that, for university students, learning to use hitting equipment, such as rackets, may be more difficult for those who have had no prior experience with racket sports like badminton or other sports that involve hitting motions.

本研究は，自己調整学習能力の観点から，高校野球選手の主体的な練習活動と競技レベルとの関係，および指導スタイルと自己調整学習能力の関係を明らかにすることを目的とした．この目的を達成するために，チームの競技レベル，あるいは各個人のチーム内の競技レベル (チーム内立場) によって自己調整学習能力に差異が認められるかどうか検討した．さらに，選手の自己調整学習能力を高める指導方法に関して，チームの運営決定権の委譲 (チームの運営方針を決定するときに指導者が選手に意識して任せること) が，自己調整学習能力を高める指導として有効であるか検討した．その結果，相対的な競技レベルが高いチームでも低いチームでも，同じチームに所属しているメンバー内での競技レベルの良し悪しを決定付けるのは，自己調整学習能力が一つの要因であることが明らかになった．また，運営決定権に関しては，指導者も選手も選手に運営決定権があると認識している「選手主導」のチームの選手は，指導者に運営決定権があると認識している「指導者主導」のチームの選手よりも高い自己調整学習能力を示したが，その差は大きなものではなかった．従って，指導者の運営決定権の委譲スタイルだけでは選手の自己調整学習能力に影響を与えることはできないということが示唆された．

Relationship of self-regulation learning ability, game power, and coaching style in high school baseball
The present study investigated relationships between players’ voluntary training and game power, and between coaching style and self-regulation learning ability in high school baseball players by examining how teams’ game power and the game power of individuals on the team affected the players’ self-regulation learning ability. Coaching methods for improving players’ self-regulation learning ability were also investigated by examining the extent that delegation of decision making authority, in which the coach left decisions about team operation to the players, improved those players’ self-regulation ability. It was found that, regardless of the degree of relative game power, self-regulation learning ability was a key to deciding the game power of the members of a team. The examination of operational decision-making authority revealed that the players on teams where both the coach and the players felt that the players could take initiatives showed higher self-regulation learning ability than the players on teams where the players felt that their coach retained the decision-making authority. However, the differences observed were rather small, suggesting that delegation of a coach’s decision-making authority may not have much effect on players’ self-regulation learning ability.

本研究では，ラジオ体操第1をヒントとして，安全かつ快適な登山に有効な「身のこなし」の獲得が期待できる「登山体操」を開発することを目的とした．まず，登山に必要とされる動きや，改善させたい身体能力を考慮し，10種類の動きを筆者が制作・提案し，共同研究者と共に動きの修正を図った．その後，修正を加えた10種類の動きをもとにダンス振付家が音楽（曲）をつけ，動きが整理された登山体操（案）が提案された．さらに，筆者と共同研究者で修正を加え，3分間で実施可能な一連の体操を完成させ，10種類の動きについて，予想される効果と動きの注意点をまとめた．完成した登山体操について，運動強度をラジオ体操第1との比較により検討した．その結果，登山体操を軽く行った場合には，ラジオ体操を軽く行った場合よりもやや負荷が高いものの，血中乳酸濃度は変化しなかった．一方，激しく行った場合には血中乳酸濃度の増加につながる高い負荷をかけられたことから，運動強度を幅広く調節することが可能であり，年齢や性別によらず，各人の体力レベルに応じて活用できると考えられた．

Development of mountaineering gymnastic exercises designed to improve movements made during mountain climbing
The aim of the present study was to develop a “mountaineering gymnastics”that could teach movements useful for safe and comfortable mountain climbing, based on hints from “radio gymnastics #1”. In Japan,“radio gymnastics” refers to a prescribed set of exercises that can be done by anyone; the participants do exercises in a set sequence while listening to an NHK radio program that provides instructions and rhythmic music. First, the present author designed ten kinds of exercises that were related to movements required for mountain climbing, while considering the physical abilities that needed to be improved. These exercises were later improved with the assistance of a colleague. A dance choreographer then added music. The author and her colleague further adjusted the exercise program so that it could be done in 3 minutes. Expected effects and points to be noted were then summarized. The intensity of these exercises was compared with the intensity of radio gymnastics #1. When these exercises were done gently, the work load was slightly higher than from doing radio gymnastics #1, but the concentration of blood lactic acid was at the same level. On the other hand, when these exercises were done vigorously, the high work load resulted in a higher concentration of blood lactic acid. This suggests that by controlling the intensity of the exercises, these mountaineering gymnastic exercises could be done by people at any level of physical strength, regardless of gender and age.

バレーボールは，世界的に競技人口も多く老若男女様々な世代が楽しむことのできる人気の高い競技であり，戦前より体育科教育の教材として位置づけられ，数多くの授業研究が行なわれ教材研究や指導法の改善がなされている．同じバレーボール種目でも，教科体育分野では，対象者の発達段階や熟達度の視点からの研究や初心者指導においての教師の教授方法についての研究が数多く行なわれている．それに対して課外体育分野では，女子小学生チームを対象とした専門的な短期指導の研究やバレーボール教室の形成的評価の活用実施の研究はあるが，教科体育分野と比べて少ないのが現状である．そこで本研究では，2016 年に開催された小学生バレーボール教室の評価の結果と，今回小学生バレーボール教室で行った授業の形成的評価の結果との違いを明らかにし，それを小学生バレーボール教室の実施教材として提供することを目的とした．小学生バレーボール教室の実施プログラムの作成や自身の行なったコーチングを参加者の評価という形でフィードバックを受けて，自己省察するための客観的な資料を得ることに本研究の意義がある．

Formative evaluation of a volleyball class for elementary school pupils
Volleyball is a popular sport, enjoyed by men and women of all ages worldwide. Since before-WWII, it has been an established part of the physical education curriculum in Japan, and many studies have aimed at improvements in teaching and coaching. In physical education, much research has been done on coaching by teachers from the point of view of its impact on students’ growth and maturity. However, the present author could find less published research on volleyball as an extracurricular activity, aside from some investigations of short-term training of elementary school girls and formative evaluation of volleyball class lessons. The present study examined differences between the results of an evaluation of elementary school volleyball lessons that was conducted in 2016 and a more recent formative evaluation, implemented a volleyball curriculum for elementary school children, and collected feedback from the participants in that curriculum so that an evaluation of the program, including the coaching, could be conducted.

スポーツ活動時に見られる一過性の水分損失は，競技パフォーマンスや認知機能を低下させる．テニス競技においても水分損失を引き起こすことが報告されており，テニス競技特有のパフォーマンスとの関連性を検討する必要がある．本研究は，テニス競技のトレーニング時における水分損失率とサービス精度との関連性を検討することを目的とした．対象者は大学テニス部に所属する健常な男子学生12名とし，30分間のテニストレーニングを実施した．測定項目は，体重，主観的運動強度(RPE)，サービス精度（それぞれトレーニング前後）および心拍数（トレーニング中）とした．トレーニング前後の体重はそれぞれ67.8 ± 8.2kgおよび67.2 ± 8.2kgで有意な減少を示した（p ＜ 0.05）．トレーニング中の平均心拍数は154.5 ± 15.5 bpm，トレーニング後の主観的運動強度(RPE)は15.0 ± 2.0だった．トレーニング前後におけるサービス精度の平均値はそれぞれ4.9 ± 1.8球および， 4.4 ± 1.5球であり，有意な変化は認められなかったが，水分損失率とサービス精度に負の相関関係が認められた(p ＜ 0.05，partial r = -0.70)．本研究により，水分損失がサービス精度の低下を引き起こす要因として考えられた．

Relation between dehydration during training and accuracy of male university tennis players' serves
Transient dehydration during sport activities lowers athletes’ competitive performance and cognitive function. In tennis, also, dehydration occurs, and its influence on performance should be examined. The present study investigated the relation between dehydration during tennis practice and service accuracy. The participants were 12 male university tennis players. For this study, they practiced tennis for 30 minutes. The measures before and after the practice included weight, rating of perceived exertion, and service accuracy; heart rate was measured during the practice. The average weight was 67.8±8.2 kg before the practice and 67.2±8.2 kg after, which was a significant decrease (p<0.05). The average heart rate during training was 154.5±15.5 bpm, and the rating of perceived exertion after training was 15.0±2.0. The average service accuracy was 4.9±1.8 balls and 4.4±1.5 balls. These differences did not reach statistical significance. A negative correlation was observed between dehydration rate and service accuracy (partial r=-0.70, p<0.05). These results suggest that dehydration may be a cause of lowered service accuracy.

A大学男子バスケットボール部に所属する2名のプレーヤーは，全国大会への出場を左右するA大学対B大学戦において，僅差で迎えた第3ピリオドの終了前，および試合終了前に全く同様のディフェンス（サイドラインからのスロー・イン時にパッサーが投じたボールにジャンプしてブロックし，オフェンスを終わらせるプレー：パスブロック）を行い，A大学の勝利に貢献する貴重なプレーとなった．本事例のようにパスブロックが2プレー出現した公式試合は非常に珍しい．彼らにインタビュー調査をしたところ，2〜5か月前にA大学体育学部の「バレーボール」の授業を受講していた．そこで，パスブロックとバレーボールのブロック技能との関係性について，対象者2名と，未受講者のバスケットボール部レギュラーメンバー2名により比較検討した．この結果，パスブロックを成功するためのポイントは，バレーボールのブロック時の腕をゼロポジションにする（ネットより手を前に出す）技能と関係していることが推察された．このことから，バスケットボール経験者がバレーボールのブロック技能を習得することは，パスブロックを成功させるために有意義であると考えられる．

Relation between blocked passes in basketball and the blocking technique in volleyball: Comparison of experts and beginners at blocking passes
Two basketball players who were students at A university participated with B university students in a selection game for a national tournament. They succeeded twice with a very effective defensive play (blocked pass) by jumping in order to block the ball thrown from the sideline by an opponent. One of these plays was before the end of the 3rd period when the scores of the two teams were separated by a narrow margin; the other was before the end of the match. Both plays contributed to A university’s victory. It is rare in an official basketball match to have two blocked passes. In their post-game interview, the players explained that they had received a volleyball lesson at their university 2 to 5 months prior to this game. In the present study, the play of those 2 basketball players and 2 regular members of the volleyball team was compared, in order to examine the relation between blocked passes in basketball and the blocking technique in volleyball. The results indicated that volleyball blocked passes were a success when the player’s arms were set at a zero position (stretching the arms beyond the net). This suggests that basketball players should acquire the volleyball blocking technique in order to be able to successfully block passes.