巻号一覧
51 巻 (2006)
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51 巻, 4 号
選択された号の論文の11件中1～11を表示しています
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総説
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和田 正信, 坂本 誠, 杉山 美奈子, 松永 智2006 年 51 巻 4 号 p. 399-408
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーSkeletal muscles induced to contract repeatedly respond with a progressive loss in their ability to generate a target force or power. This decline in function, referred to as muscle fatigue, has a complex etiology that can involve various metabolic and ionic factors. Of these, intracellular acidosis due to lactic acid accumulation has been regarded as one of the important causes of muscle fatigue that occurs with intense exercise. Recent surveys, however, have demonstrated little direct effect of acidosis on muscle function at physiological temperatures, and in fact several putative mechanisms by which intracellular changes can attenuate contractile function have been proposed. The most likely mechanisms to explain muscle fatigue include elevated inorganic phosphate concentrations that result from phosphocreatine breakdown, compartmentalized depletion of endogenous muscle glycogen and/or modification by reactive oxygen species that are produced extensively in contracting muscle fibers. This brief review seeks to examine how these three alterations contribute to muscular fatigue processes.抄録全体を表示PDF形式でダウンロード (373K) -
賀川 昌明2006 年 51 巻 4 号 p. 409-419
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーThe present paper reviews the effects and problems associated with the use of personal computers in physical education, and seeks more effective methods of use for this purpose. First, previous reports about computer use in physical education were divided into the two categories: Measurement and Assessment, and Computer-assisted Instruction or Computer-assisted Learning. Second, reports belonging to the two categories were reviewed, and checked from the viewpoint of using effects verification. Finally, the potential and the noteworthy points were discussed in relation to future use of computers in physical education. The results obtained through these steps are summarized as follows; 1. Many kinds of application software have been developed and used in physical education, but there are few reports in which strict verification of the effects has been discussed. Although limited in extent, effects at a cognitive level have been suggested in physical education classes for primary and junior high school children, and effects on knowledge acquisition and motor skill acquisition have been suggested in physical education classes for high school and college students. 2. For future effective use of computers in physical education, stricter verification of the effects through practical study involving qualitative analysis or case studies, introduction of new techniques, and adequate consideration of relevant problems are necessary.抄録全体を表示PDF形式でダウンロード (427K) -
松田 光生2006 年 51 巻 4 号 p. 421-433
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーThe age-related decrease in arterial distensibility, particularly central arterial distensibility, may increase systolic blood pressure and/or pulse pressure in the elderly. Previous studies have shown that daily physical activity is positively related with arterial distensibility, and that aerobic exercise training could improve arterial distensibility. Some likely biological mechanisms through which aerobic exercise improves arterial distensibility have been revealed. Thus, habitual physical activity and aerobic exercise training may retard age-related changes in the arteries, and prevent cardiovascular and cerebrovascular diseases in the elderly. However, more studies targeting diverse groups are needed to clarify the optimal use of aerobic exercise training in the management of arterial distensibility.抄録全体を表示PDF形式でダウンロード (459K) -
服部 恒明2006 年 51 巻 4 号 p. 435-446
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーObesity is a condition resulting from excess body fat, and is associated with several risk factors for chronic diseases in later life. Hence, the prevention of obesity is a public health priority, with much of the concern focusing on childhood and adolescence. Recently, body mass index, calculated as weight divided by height squared (BMI, kg/m2), has been widely used as a surrogate measure of adiposity for children and adolescents, and international age- and sex-specific cut-off points to define overweight and obesity have been proposed. Various surveys using the international BMI criteria have revealed that the prevalence of child obesity is accelerating throughout the developed world. However, BMI is a measure of excess weight relative to height, rather than excess body fat. The interpretation of BMI among children and adolescents is further complicated by the changes that occur in weight, height, and body composition during growth. There is a now a considerable body of evidence that during the growth stages, weight increase is frequently due to an increase in fat-free mass rather than fat mass. Therefore, application of the BMI norm to define overweight and obesity in children and adolescents should be done with caution. Furthermore, it is necessary to be aware that adopting an international standard for a specific population may introduce error because the relationship between BMI and adiposity is race-specific. For this reason, it is expected that race-specific standards of BMI with additional body composition-related information for children and adolescents will become available in the future to ensure reliable assessment of adiposity levels.抄録全体を表示PDF形式でダウンロード (388K)
原著論文
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三井 孝, 図子 浩二2006 年 51 巻 4 号 p. 447-457
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリー本研究では, 歩行中の身体を逆振り子にモデル化することにより, 高齢者の歩幅を決定する要因について検討した.
高齢者9名に, 自由歩行, 大股歩行, 最大努力による大股歩行を実施させた. 歩行中の身体を逆振り子にモデル化し, その挙動と地面反力の動態を手がかりにして, 歩幅の増大にともなう歩行特性の変化を検討した. その結果, 歩幅の増大にともない振り子の振れ幅は増加し, 接地後大きな地面反力が生じる際に振り子の脚長は縮むこと, その後伸びながら推進力を発揮していることが認められた. これらのことは, 大きな歩幅を獲得するためには, 接地足を中心にして, 身体を後方から前方へと大きく逆振り子型に回転させることが重要であり, そのためには, 下肢の伸張―短縮サイクル運動を遂行する能力が極めて重要な役割を果たすことを示唆するものである.抄録全体を表示PDF形式でダウンロード (392K) -
奥村 基生, 吉田 茂2006 年 51 巻 4 号 p. 459-470
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリー本研究では, 熟練・準熟練群の大学生の剣道選手における反応選択の処理効率の熟練差を検討した. ここでは, 被験者の技知識を確認して実験条件を設定した. そして, その条件に対する運動技能の獲得度合と, 反応選択の処理効率を検討する2実験課題を実施した. まず, 技能確認実験では熟練差はなく, 条件の低・中難度に対する両群の運動技能の獲得が概ね確認された. 反応選択実験では, 技知識の活用頻度, 時間効率, 技能発揮において熟練差が認められた. 熟練群の思考内容と技知識の繁用は, 予測による能動的な反応選択を多用することを示していた. また, その知識の繁用は, 環境に存在する干渉への耐性を頑健にするように処理機能を向上させる. 一方, 準熟練群は, 処理機能が干渉に対して脆弱であるために技知識を活用することができず, 受動的な反応選択を強いられると考えられた. この採用する処理様相の能動性・受動性と処理機能の頑健性・脆弱性の相違が, 反応選択における時間効率と技能発揮の処理効率の熟練差をもたらしていた. すなわち, 剣道では, 技知識を活用した予測による能動的な反応選択が重要であることが示された. 競技実践者は, 有効な技知識を獲得し, 反応選択でこれを多用する中で, 知識の洗練と処理機能の強化を図るべきである.抄録全体を表示PDF形式でダウンロード (2550K) -
林 容市, 沼尾 成晴, 中垣内 真樹, 田中 喜代次2006 年 51 巻 4 号 p. 471-481
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーThe safety of cardiorespiratory function is an accentuated factor in exercise prescription for improvement of physical fitness. When regulating exercise intensity using a self-selected exercise intensity (SSEI) method, it is important to not only consider responses in cardiorespiratory function but also the safety of exercise intensity. In this study, therefore, we compared changes in cardiorespiratory function during exercise at anaerobic threshold (AT) and by the SSEI method. In addition, we attempted to acquire new information regarding the safety of the SSEI method. Group 1 consisted of 28 healthy men, aged 25.5 ± 2.7 years, who completed two 20-min exercise trials. During the first trial, participants performed cycling for 20 min by the SSEI method (SS-trial). The second trial consisted of 5 min of fixed-load cycling at 70% (high intensity) of Vo2max (SSFL70%) followed by 15 min of cycling at SSEI. Group 2 consisted of 10 healthy men (25.0 ± 1.8 years) who completed two 20-min exercise trials at AT (AT-trial) and Above AT (AbAT-trial). Oxygen uptake during the SS-trial increased to the same level as that during the AT-trial. However, it was noteworthy that the exercise intensity selected by each subject was maintained at approximately 65%Vo2max during SSFL70%. These data suggest that a constant-load exercise relative to AbAT level can be sustained for a prolonged period of time without inducing a marked risk for the cardiorespiratory system.抄録全体を表示PDF形式でダウンロード (412K) -
高橋 仁大, 前田 明, 西薗 秀嗣, 倉田 博2006 年 51 巻 4 号 p. 483-492
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーThe purpose of the present study was to elucidate tactical strategies for winning a tennis match. Forty-two men's singles matches in the 1997 and 1998 Kyushu collegiate tennis championships were analyzed. Analytical criteria were the relationship between point-winning at each score and the techniques used. In the present research, techniques were categorized into the following 5 groups: service, return, stroke, offense and defense. The following results were obtained: 1. Stroke was the most frequently utilized technique regardless of point-winning. 2. Return and defense techniques, which are considered “passive” techniques, produced significantly high rates of point-losing. 3. The rate of point-winning by service was low at high rate counts (HRC), but high at low rate counts (LRC). In contrast, the rate of point-losing by service was high at LRC-game-points. The rate of point-winning by service was higher for players leading in score, and was low at important scores. 4. The rate of point-winning by players using the defense technique was high at HRC-opponent's game-points. To win a point using passive techniques is the most important tactic at opponent's game-points. 5. The rate of point-losing during the offense technique was high at LRC-up counts. Offense techniques are effective for winning points; however, they involve a higher risk of losing points. These results indicate that players should analyze the relationship between point-winning and strategies at each score.抄録全体を表示PDF形式でダウンロード (291K) -
佐々木 万丈2006 年 51 巻 4 号 p. 493-503
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーThis study examined the relationship between precompetitive state anxiety and competitive trait anxiety, sport motivation, sport achievement orientation, stress appraisal, and stress coping prior to competition. Sixty-five male junior high school baseball players responded to the Competitive State Anxiety Inventory-2 (CSAI-2) on three occasions during the precompetition period: 1 week, 2 days, and 1 day before competition. They also completed a series of questionnaires 1 week prior to competition, measuring sport competitive trait anxiety (SCAT-C), sport achievement goals (TEOSQ), sport motivation (SMS), and their stress appraisal and stress-coping style when they were unable to exhibit anticipated performances in their club activity. Path analyses were employed in order to clarify the dependence of these psychological factors on the basis of the Lazarus stress model (Lazarus and Folkman, 1984). It was found that the junior high school baseball players were distressed, reported high precompetitive trait anxiety and high amotivation, or reported themselves to have a high intrinsic motivation to accomplish their goal, when they felt they were unable to fulfill assignments during club activity. However, players who considered that they could cope positively with stressful circumstances reported low precompetitive state anxiety.抄録全体を表示PDF形式でダウンロード (425K) -
坂東 美和子, 田辺 智, 伊藤 章2006 年 51 巻 4 号 p. 505-514
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリー4ターン投法でパフォーマンスが異なる (世界のトップレベルから地方学生レベルまで) 26名の成人男子ハンマー投げ選手の公式競技会における投てきのハンマーヘッドの運動を三次元解析し, 以下の結果を得た.
記録の良い選手ほどヘッドの初速度が高い傾向にあったが (r=0.917, p<0.001), 記録とリリース高および投射角との間には有意な相関関係が認められなかった. すべてのターンにおけるヘッド速度の最大値と最小値は記録との間で有意な正の相関関係が認められた. 指導現場では1ターン目は速度を遅くし, 徐々に加速するように指導する傾向があるが, 本研究の結果では優秀選手が速い回転速度で1ターン目を開始しており, 異なる結果を得た. また, 指導現場ではヘッドの軌道を規定する曲率半径を大きくするように指導がなされる場合があるが, 本研究の結果では曲率半径が短い局面でヘッドが加速しており, また曲率半径が短い局面で法線加速度が増加する傾向が観察された. そして, 記録の良い選手ほど法線加速度が高く, 法線加速度の発揮速度も高かった.
以上の結果を先行研究を参考にまとめると, ハンマー投げの選手は回転の中心方向にヘッドを引くことによって法線加速度を高め, その結果曲率半径が減少しながらヘッドを加速する可能性が示唆された.抄録全体を表示PDF形式でダウンロード (425K) -
武田 剛, 市川 浩, 杉本 誠二, 野村 武男2006 年 51 巻 4 号 p. 515-524
発行日: 2006年
公開日: 2008/01/25
ジャーナル フリーThe starting technique is one of the most important factors for sprint performance in competitive swimming. Take-off velocity and take-off angle determine the horizontal take-off velocity and flight distance in the aerial phase. The most appropriate take-off angle for start performance has not been investigated, although the importance of take-off velocity is well known. The purpose of this study was to clarify the effects of take-off angle on take-off velocity, flight distance and block time during swim-start. Twelve elite competitive swimmers performed three different types of start trial. In the experimental starting trials, swimmers were instructed to take off from the starting block higher (High) and lower (Low) than the usual grab start trial (Normal). The starting motions of subjects were recorded by a high-speed camera (Photron FAST-CAM PCI, 250 fps) and the 2D-DLT method was used for calculating the kinematic variables. The starting movement was modeled by a pendulum model, and the take-off velocity was resolved to the rotational component and the extensional component. A decrement of the take-off angle resulted in an increment of rotational component, extensional component of take-off velocity. Therefore, the decrement of flight distance with decrement of the take-off angle resulted in fewer disadvantages for start performance. In addition, there was no correlation between take-off angle and the block time in Normal trials. Considering the importance of horizontal take-off velocity, which is in the direction of swimming, take-off angle should be approximately 0 degree in the aerial phase.抄録全体を表示PDF形式でダウンロード (470K)
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