本研究では，バスケットボールのドライブ動作の踏み出し動作およびドライブ方向の違いが運動パフォーマンスに及ぼす影響について明らかにすることを目的とした．ここでは，左右ドライブ方向と，2つのステップ条件(openとcross)の4条件のドライブ動作を分析し，条件間の計測項目の違いを調査した．大学男子バスケットボール選手10名を対象とした．動作計測では，対象者の前方にディフェンダーに見立てたポールを配置し，対象者にはこのポールをかわしてドライブ動作をするよう指示した．光学式3次元動作分析装置と床反力計を用いて，動作を分析した．運動パフォーマンスは，反応時間，移動速度，軸脚で発揮される推進力および体幹回旋角度のパラメータで評価した．本研究より，以下の知見を得た．ドライブ動作時のステップ動作の違いによって反応時間に有意差は認められない．openステップに比べ，crossステップの方が大きな推進力を発揮できるため，ポールの横をすり抜ける際の移動速度が有意に大きくなる．ステップ動作の違いは体幹回旋角度に影響を及ぼし，crossステップよりもopenステップ方が，回旋角度が大きかった.

Effects of different steps when driving forward on athletic performance in basketball
The present study examined effects on basketball players’ performance of differences in stepping movements and the direction of a player’s drive, under a total of four conditions: driving to the left or right combined with stepping with open steps or cross steps. The participants were ten male university basketball players. A pole resembling a defender was placed in front of a participant, and the participant was instructed to dodge the defender (the pole) and drive forward, either to the left or to the right. An optical 3D motion analyzer and force plates measuring the force on the floor were used to analyze the participants’ movements. The participants’ performance was evaluated from their reaction time, the speed of their movements, the driving force of their axial leg, and the angle of rotation of their body. The results were as follows: (a) no significant difference was found in reaction time between the two types of stepping movements when the participants were driving forward, (b) cross steps were associated with significantly faster movement when the participants were passing by the side of the pole, perhaps because cross steps provide a greater propulsive force than open steps, (c) differences between the two stepping movements affected the angle of rotation of the body, and (d) the angle of rotation was greater when the participants used open steps than when they used cross steps.

本研究では，疾走能力を高めるための練習手段として考えられている高速スキップ運動を取り上げ，体育専攻学生を対象として，高速スキップ運動の動作を観察的動作評価法により類型化し，類型化された動作の客観的特徴を明らかにすると同時に，疾走運動との関係を明らかにすることを目的とした．その結果，作成した高速スキップ運動の評価基準を用いた潜在クラス分析より，対象者の高速スキップ運動の動作は3クラスに分類された．3クラスでは，動作評価の合計得点が高いクラスほど，高速スキップ運動の速度や地面反力が有意に大きいことが明らかとなった．また，高速スキップ運動と疾走運動との関係性について検討すると，高速スキップ運動のクラス毎に疾走運動の速度が異なることや速度を含めた時空間変数にも相互に有意な相関関係があることが確認された．このことは，高速スキップ運動において動作タイプを把握して，速度を向上させる動作改善等を行うことで，疾走運動の速度を改善させる可能性を示している．

Relationship between type of movement in high-speed skips exercises and sprinting performances
The present study examined a high-speed skips exercise that is generally considered to be an effective training method for improving sprinting performances. The participants were 34 university male students who were majoring in physical education. An observational method was used to evaluate their movements when doing high-speed skips. The movements were classified into patterns to clarify their objective features and the relationship of the high-speed skipping movements and sprinting performances. Latent class analysis was used to classify the participants’ high-speed skips movements into 3 categories according to a standard developed for evaluating these movements. In this evaluation, the greater the number of total points given to the participants’ movements, the faster the speed and the stronger the ground reaction force of their high-speed skips movements. An analysis of the relationship between the participants’ high-speed skips movements and their performances in the sprint confirmed that their sprinting speed differed among the categories of high-speed skips movements. In addition, the spatiotemporal variables, including speed, were significantly correlated with each other. These results suggest that sprinting speed may be improved through an understanding of movement types in the high-speed skips exercise.

フィギュアスケートのジャンプの得点は難易度に応じた基礎点と，質を表す出来栄え点の合計で決まり，回転不足と判定されれば多くの場合両方で減点されてしまう．回転不足判定の基準は競技規則中に明文化されているが，規則に関する講習会の参加はインストラクターなどに限られ，一競技者に対しては行われていない．また，競技者が判定基準について共通認識を得ることができているかを調査した研究は見当たらない．本研究では放映映像を用いて大学部活動部員にジャンプの回転不足判定を行ってもらい,実際の競技結果と比較検討を行った．結果，競技者の持つ判定基準の認識が実際のものよりも甘い可能性を示した．また，所持級・競技歴・インストラクターの指導頻度について,中央値を閾値として２群に分け正解率の差の検定を行ったところ，インストラクターの指導頻度が高い群が低い群に比べて有意に正解率が高かった．これは競技者が独学で判定基準を理解する学習機会が限定的であることが原因と考えられる．競技者が自身のパフォーマンスを評価し，適切な技術向上サイクルをまわすためにも，判定基準の共通認識を形成できるための環境整備が求められるのではないか．

Judging under-rotation in figure skating: university figure skaters' understanding of the scoring rules
The scoring of jumps in figure skating is determined from a combination of points for technical difficulty and for quality. If a jump is judged to be under-rotated, points are generally deducted from both of those scores. The standards for judging a jump to be under-rotated are defined in the official competition rules. Seminars on the rules are provided for coaches, but not for skaters. Further, the present authors were unable to find any published investigation of skaters’ understanding of judges’ scoring standards. The present study compared university skate club members’ judgments of under-rotations to judgments made in actual competitions, using videos of competitions that had been broadcast. The results suggested that the university skaters’ judgments tended to be more lenient than the ones made by the competition judges. For the analysis, the participants (N=22) were divided into two groups at the median. The scoring by the skaters who had had more coaching corresponded more closely to that of the competition judges than did the scoring by the skaters who had had less coaching. This may be a result of the skaters having had very limited opportunities to learn the standard scoring criteria on their own. In order for skaters to be able to evaluate their own performance and improve their technique, it may be necessary to establish a system in which judges and skaters can come to a common understanding of the scoring standards.

競泳のキックスタートでは左右の脚を前後に開き，スタート姿勢を構える．本研究ではスタート姿勢を構える際，脚筋力が大きい脚を前後どちらに配置することが望ましいか，スタートパフォーマンスに及ぼす影響から検討することを目的とした．対象は，16名の男女大学競泳選手とし，左右脚の前後配置を交互に入れ替えさせ，合計4本のキックスタートを実施させた．脚筋力については，膝関節伸展方向への等尺性最大筋力を左右それぞれ計測し，脚筋力の大きい脚を判定した．測定項目は，跳び出し速度，跳び出し水平速度，跳び出し垂直速度および跳び出し角度を算出した．その結果，脚筋力が大きい脚を前方に配置したスタート姿勢において，跳び出し速度および跳び出し水平速度が有意に高い値を示していた．したがって，脚筋力が大きい脚を前方に配置することは，キックスタートパフォーマンスを向上させる可能性があることが示唆された.

Effects of leg position on kick start performance: considering leg strength
In the kick start, swimmers put one foot on the front edge of the starting block, and the other foot on the back plate. The present study compared effects of competitive swimmers’ foot position on their kick start performance, specifically on whether their stronger leg was placed in the front or the rear. College swimmers (12 male, 4 female) performed 4 kick starts, alternately using their preferred and non-preferred combination of front and rear foot positions. A Biodex System 3™ was used to measure the isometric maximal voluntary contraction of the extension of both of the swimmers’ knees, in order to determine which was the stronger leg. Other measures analyzed were start parameters, that is, the take-off horizontal and vertical svelocities and the take-off angle. The take-off velocity and the horizontal take-off velocities with the stronger leg on the front edge of the starting block were significantly higher than with the weaker leg in that position. These results suggest that positioning the stronger leg in front may improve kick-start performance.

本研究は，女子剣道競技者の中段の構えにおける左足に着目し，体重配分の違いが打撃時間(光刺激点灯時から剣先が打ち込み台を捉えるまでの時間)と踏み切り動作中の左足の地面反力に及ぼす影響を明らかにすることを目的とし，調査して以下の結果を得た．なお，本研究の結果は，相手の動作に反応し相打ちを制する面技を想定した，光刺激を用いた打撃試技によるものである．(1) 中段の構えにおいて左足への体重配分の割合は個人で異なる．(2) 中段の構えでは左足への体重配分が小さい傾向にある．(3) 中段の構えで体重を左足へ配分すると打撃時間が長くなる．(4) 右足配分群と左足配分群において打撃動作に伴う左足の前後・鉛直方向の地面反力の最大値(体重を100%とした場合の割合)には違いがない．以上のことから，中段の構えにおける体重配分が，打撃時間を短くする手立ての１つになる可能性を示した．また，相手の動作の起こりを狙い，その起こりに反応し面を打撃する際に打撃時間を短くするための技術的な課題に対しては，女子剣道競技者でも左足への体重配分を小さくすることが有効な手段といえる.

Female kendokas' weight distribution, striking time, and ground reaction force at striking in the middle attack posture: controlling aiuchi by reacting to the opponent's moves
The present study examined influences of body weight distribution on the striking time (the time between the starting light signal and the sword point touching the target, i.e., a kendoka's reaction time), and on the ground reaction force against the kendoka's left foot during the takeoff movement. The participants were 10 female kendoka, with an average kendo experience of 14 years. The following results were obtained from striking attempts that assumed an aiuchi with a men strike against the opponent's moves: At a middle attack posture, (a) the proportion of weight distributed to the left foot varied from person to person, (b) the proportion of weight distributed to the left foot tended to be small, and (c) the distribution of a large amount of weight to the left foot prolonged the striking time. Also, no difference was found between the right foot distribution group and the left foot distribution group in the maximum ground reaction force of the front and rear direction and the vertical direction (provided that the body weight was 100%) against the left foot in the striking motion. These results suggest that body weight distribution in a middle attack posture offers the possibility of shortening the striking time. For female kendoka, a possible effective solution to the technical problem of shortening the striking time with a men attack by reacting to the start of the opponent’s moves may be to distribute less of the body weight to the left foot.

本研究は大学野球における走塁指導の示唆を得るために，二塁ランナーの第二リードの位置が本塁への走塁時間に与える影響を検討した．参加者は大学野球選手24 名であった．第二リードの位置はABC三つの位置とした．二塁ベースから三塁ベースへ向かって塁線上に８ｍ進んだ位置をA，塁線上から２ｍ外野寄りで二塁ベースから8ｍの位置をB，塁線上から4ｍ外野寄りで二塁ベースから8ｍ位置をC とした．各位置から本塁へまでの走塁時間を計測して比較した．その結果，C位置からのスタートはA 位置，B 位置からのスタートより走塁時間が有意に長かった．A位置とB 位置からのスタートでは有意な差はみられなかった．その結果，二塁ランナーの第二リードを外野手寄りの４ｍ以上後方にとるメリットはないと考えられた．

Comparison of effects of various lead off positions for a second base runner to run to home base in university baseball
The present study examined effects of the lead off position of a runner on second base on the time required to reach home base. The participants were 24 male university baseball players. Three lead off positions, A, B, and C, were compared. Each position was 8 meters away from second base toward third base. Position A was directly on the baseline, position B deviated 2 meters toward the outfield, and position C deviated 4 meters toward the outfield. The time required for running from each lead off position to home base was compared. The time from position C was significantly longer than from positions A and B, whereas no significant difference was found between positions A and B in the time to reach home base. This suggests that there is no advantage in taking a lead off second base that is more than 2 meters toward the outfield.

本研究は，走幅跳を専門とする大学女子競技者が大学進学後も競技力を向上させ続け，大学4年次において日本トップレベルに至った取り組み事例を報告するものである．取り組みの中で，大幅な競技力向上に影響を及ぼしたのは，技術的な変更・改善であり，特に空中動作をはさみ跳びに変更したこと，踏切動作を改善したことであった．また，技術的な変更・改善を行うきっかけは，試合・練習での振り返りを充実させて，技術的・体力的な課題を明確にすることであった．様々な取り組みの結果，自己最高記録を5.92(+0.9)mから6.31(+1.8)mへ延伸することができた．本研究で提示した事例は，走幅跳競技者および指導者にとって，大学進学以降も競技力を向上させるための有益な知見の1つとなる可能性が示唆された．

Improvement of movements at take off and in the jump's flight phase by a female athlete who became one of Japan's top-level long jumpers while a university student
The present study reports activities of a female long jumper who continued training for 4 years while a university student and who became one of Japan’s top-level long jumpers. Keys that may have helped her in training to make a significant improvement in her jumps were mainly technical changes in her style of take off and her form during the flight phase of the jump, which she changed to a scissors kick. Those improvements were developed from a detailed review of the results of her jumps in competition and training in order to identify any technical and physical problems. After implementing the proposed revisions in her training, her personal best record improved from 5.92 (+0.9) meters to 6.31 (+1.8) meters. This may provide useful information for other long jumpers and coaches as to how to improve jumpers' performance even after they become university students.

本研究では，水泳のインターバルトレーニングにおける運動強度とその実施順序の違いが泳者の生理的応答に及ぼす影響について調査し，競泳競技の選手やコーチがインターバルトレーニングを実施する際の実践的な活用方法の提言を目的とした．実験は，大学生男子競泳選手4名を対象に，実験用回流水槽にてクロール泳で実施した．実験に先立ち，最大酸素摂取量（VO2max）計測を行い，各対象者におけるVO2max出現時の泳速度の100%（v100%VO2max），90%（v90%VO2max），80%（v80%VO2max）の3つの泳速度を設定した．さらに，3つの泳速度を組み合わせることで，以下の3条件を設けた．�@v90%VO2maxの後にv90%VO2max（90-90条件），�Av100%VO2maxの後にv80%VO2max（100-80条件），�Bv80%VO2maxの後にv100%VO2max（80-100条件）．実験中の泳速度は回流水槽の流速を変化させることで調整し，強度によって泳時間と休息時間を増減させる実験プロトコルを採用した．その結果，全ての対象者の酸素摂取量と心拍数の平均値が100-80条件で最も高い値を示した．血中乳酸濃度は80-100条件で最も高い値を示され，90-90条件で最も低い値が示された．以上のことから，競泳でインターバルトレーニングを行う際に，運動強度とその実施順序の違いが有酸素性及び無酸素性の代謝に影響を与える可能性が示唆された．

A case study of the effect of interval swimming training intensity and its sequence on physiological responses
The purpose of this study was to examine the effect of exercise intensity and its sequence on physiological responses during interval swimming training and to suggest practical interval training methods for swimmers and coaches. Four male college swimmers participated and swam front crawl swimming in a swimming flume. For each swimmer, the maximal oxygen uptake (VO2max) measurements were conducted prior to the experiment, and three swimming speeds were obtained, which were 100% (v100%VO2max), 90% (v90%VO2max), and 80% (v80%VO2max) of the swimming speed at which VO2max was observed. By combining those three swimming speeds, the following three conditions were established: a) v90%VO2max followed by v90%VO2max (90-90 trial), b) v100%VO2max followed by v80%VO2max (100-80 trial), and c) v80%VO2max followed by 100%VO2max (80-100 trial). The swimming speed was controlled by changing the flow speed in the flume, and the exercise duration and rest interval were adjusted depending on the combination of the intensities. For all swimmers, the highest averaged oxygen uptake and heart rate were observed in 100-80 trial. The swimmers’ blood lactate concentration was highest in 80-100 trial and lowest in 90-90 trial. These results suggested that differences in exercise intensity and its sequence during interval swimming training could affect aerobic and anaerobic metabolism.

本研究はコロナ禍の部活動での自主的・自発的な活動を促す指導方法の具体的な取り組み事例を提示し，集合的効力感尺度から評価することでコロナ禍での取り組みの有効性を検討する．具体的な取り組みは，筋力・柔軟性・ラグビーのトレーニング動画の配信，オンラインでのトレーニングやミーティングの実施，12分間走や前屈チャレンジの九つの活動であった．このような活動に加え，部活動の運営については，学生の代表であるキャプテンと事前に話し合いを行った上で決定した．集合的効力感尺度の調査は52名の部員に対しシーズン開幕前に実施し，40名の回答が得られた．その結果，総合得点で3.54±1.00であり，参考値の3.49±0.71と比べて僅かに高く，下位尺度は，「準備力」が高く，「能力」が低いことが明らかとなった．以上のことから，オンラインの活動においても集合的効力感を維持することが可能であり，その有効性は示唆された．さらに，このことはコロナ禍以前より推進されていた部活動改革の，外部指導者不足の解消や地域展開の推進に寄与する資料となることが期待される．今後は，オンラインの活動において獲得できるもの，逆に対面の活動でしか得られないものを分別していくことで，ハイブリット型の運動部活動を実現できることが期待される．

Verification of a method for continuing sports club activities during the coronavirus pandemic: from the point of view of collective efficacy
The present study examined, from the point of view of collective efficacy (in this case, the sports club members’ shared confidence in the ability of the members of the club), the value of some coaching programs for encouraging voluntary activities at a sports club, in the context of the restrictions related to the coronavirus pandemic. The programs consisted of 9 activities, including YouTube videos demonstrating how to improve muscle strength, flexibility, and rugby performance; on-line training and meetings; and 12-minute running and forward-bend exercises. Management of the club’s activities was decided through discussions with the team captain, who represented the students. A nine-question collective efficacy scale, with 5 sub-scales: ability, effort, endurance, preparation, and solidarity, was sent to 52 club members before the start of the season; 40 replies were obtained. The mean score on the collective efficacy scale was 3.54±1.00 which was slightly higher than a published reference value of 3.49±0.71. The sub-scale scores were higher on preparation and lower on ability. The above results suggest that the special program was effective because it was possible to maintain collective efficacy even when relying on-line activities. It may be possible to utilize these coaching programs as reference materials in situations in which there is a shortage of outside coaches and for promotions intended to expand local support for the rugby club. Such hybrid sports club activities could possibly be implemented by dividing activities into those that can be done on-line and those that can only be done face-to-face.

高等学校におけるダンス部の活動は，初心者が多いことが報告されており，2時間程度の練習内で，ダンスの基礎基本となる動作を身に付けるためには，30分程度でウォーミングアップを効率良く実施する必要があると考えられた．そこで，部活動の時間の中で，短時間で効率よくダンスのテクニックを身につけることができるウォーミングアップを作成することを目的とした．今回は江口が示した基本運動もとに，新たなウォーミングアップを作成し，2校の高等学校ダンス部で実践した．その結果，ウォーミングアップを実践した2校ともに，�Gの脚上げステップの実施に課題を抱えており，ジャンプしながらのスムーズな移動に課題が認められた．そこで，プリエの動作を使ったジャンプの項目を追加で作成した．動きを追加で作成した結果，「エチュード（練習曲）としての基本運動第一課程」の動きとの関連をみると，1番〜6番のすべての運動の種類を網羅することとなった（表２）．さらに，�@〜�Iまでのウォーミングアップを簡易に実施できるレベルに達した部員がより発展的な柔軟性の獲得を目指す場合を想定し，発展的な動きについても検討することができた．今後は，本研究で作成したウォーミングアップの成果と課題について，客観的な指標を用いて，より科学的に検証し，よりよいウォーミングアップについて検討していきたい．

A brief warm-up routine before dance club lessons developed for a high school dance club whose members are mostly beginners
Typically, many high school dance club members are beginners at dance, and, in order for them to learn basic dance techniques in 2 hours, the warm-up time has to be limited to 30 minutes. The present study aimed at developing a warm-up routine that would enable the club members to learn dance techniques efficiently while staying within the limited time available for the club’s activities. Based on the basic motions described by Eguchi (1968; in Japanese), a new warm-up routine was designed and implemented for 2 high school dance clubs. At both schools, the leg-up step in No. 8 seemed to be difficult for the students, and moving smoothly while jumping was also a problem. However, after a jump item using a plie motion was added, all the movements in Nos. 1 through 6 could be included in relation to the basic motion lesson 1, as Etude (see Table 2). In addition, more advanced motions were studied, because it was assumed that some members would become able to perform warm-up exercises Nos. 1-10 easily. As a next step, the results and the problems of warm-up that were examined in the present study should be further investigated by using objective indices in order to develop even better warm-up routines.