We have proposed a new optimum trajectory planning method for a system with nonholonomic constraints due to passive joints based on a function approximation method. The trajectory is approximated by a linear combination of Hermite functions and Fourier series. The combination variables are solved by a nonlinear programming method that considers the constraints in the same function space as that of the trajectory. We have examined the validity and features of this method by applying it to the optimum trajectory planning of a steady giant swing motion. It is found that this method has efficient convergence characteristics in regards to iteration calculation and can provide accurate solutions depending on the order number of the approximating functions. Optimum giant swings with no input torque can be obtained for various motion periods.

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モーグル（モーグル）は，その競技特性から，下肢を中心とした衝撃吸収能力，身体操作性，体幹の安定などが極めて高い次元で要求される．モーグルはダイナミックかつエキサイティングな競技である一方，膝靱帯損傷，腰痛症，脳振盪などの外傷・障害と常に隣り合わせである．本稿では，競技力向上と外傷予防のための，年間を通じた体力測定，コンディショニング，動作解析研究などの取り組みについて紹介した．

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The purposes of this study were to estimate exercise intensity during mogul skiing using heart rate and to clarify the physiological characteristics of mogul skiing using blood lactate concentration. Additionally, to clarify the characteristics of mogul skiing by comparison, a 40-s incline side jump test and mogul ski performance points were compared. Six male and six female subjects belonging to the Japanese national ski team took part in this study. The study took place at the moguls World Cup in Tazawako, Akita, Japan. Blood lactate concentrations were measured three, five, and seven minutes after the finish using a lactate auto analyzer. Additionally, relative blood lactate concentration was calculated with respect to the maximum blood lactate concentration, which was measured after the 40-s incline side jump test. Three male and three female participants took part in the heart rate measurement during the competition. To estimate exercise intensity, relative heart rate during the competition was calculated with respect to the maximum heart rate measured during the maximum oxygen uptake test. To evaluate the relationships between lactate concentration and time point and between the number of 40-s incline side jumps, lactate concentration after the 40-s incline side jump test and time point, Pearson's correlation coeffcient was tested. The average maximum blood lactate concentration after the competition was 7.6mmol・L-1 for the males and 8.6mmol・L-1 for the females. The aｖerage heart rate during the competition was 182.3bpm for the males and 182.8bpm for the females. There was no correlation between lactate concentration and time point; however, there was a positive correlation between the number of 40-s incline side jumps and time point. Based on the results of this study, mogul skiing can be defned as a high-intensity exercise requiring anaerobic endurance.

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Cork720 is a Ski Slopestyle jump trick, in which a skier's body rotates around an axis that is tilted away from the vertical and horizontal axis. The purpose of this study was to analyze the takeoff characteristics of the Cork720 of a Japanese top skier by comparing with the Upright 720 which rotates around the vertical axis. The subject was 1 top level male Ski Slopestyle athlete belonging to the Japanese national team（ age: 20years, height: 168cm, weight: 64kg）. Data were collected at a waterramp which is a typical off-season training facility for Freestyle ski. Two high speed video cameras were used to film from both sides of the jump and the three-dimensional（3-D） coordinate values were calculated by using the DLT method. Angles of the backward and sideward tilt of the body, the joint angles of the knees and hips, shoulder and hip rotation angles were analyzed. It was found that the takeoff motions of the Upright720 and Cork720 were similar, though Cork720 had larger back tilt of the body, the extension of the right knee and hip was larger, and the shoulder and hip started to rotate earlier. The side tilt of the body was thought to be the main factor to create the tilted axis of Cork720, and also would be the greatest difference between the two tricks, but in this case, it resulted that the side tilt of the body was almost the same. From these results, it was suggested that in this case, the tilted axis of the Cork720 was made by the back tilt of the body and the extension of the right knee joint and the right hip joint.

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【はじめに】
　スキーは，日本で最も楽しまれているスポーツのうちの1つである．そのなかで（モーグル）は競技としては新しく，コブ斜面を一気に滑走し，2回のエアー（ジャンプ）を組み合わせて行うという種目であり，スキー競技の中でも危険度が高いスポーツであるといえる．
　今回，2003年10月14日から11月1日までスイスにて行われた全日本モーグルチームの合宿に理学療法士として参加する機会を得た．その際実施したメディカルチェックの結果，7名中7名にてOber test陽性，うち3名に膝蓋腱炎（内側）の既往があった．1名は，チェック実施時にも同部の疼痛を有していた．
　我々はフリースタイルモーグルスキー選手にみられた膝蓋腱炎の発生メカニズムについて考察し，若干の知見を得られたので報告する．
【症例】
　27歳女性．モーグルスキー歴9年．4年程前よりスキー練習中膝蓋腱内側に疼痛有し，超音波及び電気治療などを受けていたが，増大時にはステロイド注射にてコントロールしていた．2002年12月右MCL損傷後，膝蓋腱の疼痛増大していた．2003年10月初期評価実施．両Frog eye．右Patella下位．筋力右膝関節伸展筋，両股関節外転筋，内転筋低下．Ober test陽性．大腿四頭筋柔軟性に左右差あり．片脚スクワットでknee in傾向．膝蓋骨可動性低下．圧痛は膝蓋骨下内側部にあり，運動開始時，あるいは疲労を感じてくると疼痛出現．自発痛はなかった．これらの評価に基づき，超音波，腸脛靭帯や大腿四頭筋に対するストレッチング，膝蓋骨に対するモビライゼーション，3 point Straight Leg Raising，片脚スクワット，片脚バランスなどを指導した．また腱炎に有効とされる遠心性収縮を用いての筋力強化も行った．練習後には，必ずアイシングを行わせた．
【結果】
　合宿中であったにもかかわらず，疼痛をコントロールすることができた．疼痛は膝蓋骨下内側部にのみ限局して存在したが，他部位に広がることはなかった．膝蓋骨の可動性も増大した．
【考察】
　疼痛をコントロールできた理由として，アイシング実施による炎症の最小限化，膝蓋骨の可動性が増大，遠心性収縮を利用した筋力強化などを用いたためと考えられた．
　スキー滑走姿勢が常に体幹前傾，股関節屈曲・膝関節屈曲位であるため，腸脛靭帯は短縮しやすい肢位であるといえる．その際下肢は外旋位をとり，膝蓋骨は外側変位となり，膝蓋腱内側部にストレスが加わると考えられた．したがって，今後は本症例だけではなく同様の受傷を回避するために，他選手にも腸脛靭帯のストレッチングを意識的に実施させるべきであると考えられた．

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In this paper, the control problem of the landing attitude of a somersault is considered by applying the optimal control theory and a cascade neural network model. A physical model for a human being is fundamentally modelled with a two-link model. First, by solving the nonlinear optimal control problem, the optimal torque to control the landing attitude was obtained. Second, in the application of neural network, the motion of a somersault was evaluated by performing computer simulations and then a control torque was obtained by the back propagation method. As a result, it was demonstrated that in both methods, the landing attitude can be controlled, and the control torque obtained from the neural network is similar to the one from the optimal control theory.

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We have already proposed the “rings gymnastic robot” that has free-floating characteristics of gripping point. The purpose of this paper is to acquire performance skill represented by fuzzy rules to realize one of the compulsory requirements, i.e., a backward giant circle from handstand to handstand, in the rings event through the robot. In controlling the performance, it is divided into three basic exercises and one of fuzzy controllers for the basic exercises is selected according to the situation. In order to acquire parameters of the controllers, an evaluation method based on five shbgroups is applied to genetic algorithm. A subgroup has independent evaluation and priority exists among the subgroups. Simulation results show the effectiveness of the performance skill obtained and the evaluation method proposed.

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The rings event is one of men's apparatus gymnastics, and has free-floating characteristics at the gripping point that do not exist in the other gymnastic events. In this paper, we propose a rings gymnastic robot intended to apply it to the coaching. Joint torque in exercises is informative for the coaching and gymnasts can easily obtain the knowledge to realize exercises if a control law of the torque is represented as "if-then" rules. Therefore, we adopt fuzzy control as a control strategy for the rings gymnastic robot. The purpose of this paper is to acquire suitable fuzzy rules for realizing a series of exercises, which is a handstand from backward giant circle. Simulation results show the effectiveness of the fuzzy rules and a guideline for the coaching can be read from the fuzzy rules.

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【目的】
近年、関節鏡視下手術の進歩は目覚しく、半月板損傷の手術療法は鏡視下縫合術や部分切除術が広く行われている。また、円板状半月板障害に対しても鏡視下半月板形成的切除術が主流となっている。半月板損傷に対する縫合術や部分切除術後のリハビリテーションに関する文献は多いが、円板状半月板形成的切除術後のものは散見する程度であり、さらにスポーツ選手の術後スポーツ復帰に関するまとまった報告は、我々の知り得た範囲では存在しなかった。そこで今回我々は、スポーツ選手における円板状半月板形成的切除術後のスポーツ復帰の実際を報告する。
【対象および方法】
当院において1997年5月～2003年10月までに膝円板状半月板障害に対し、鏡視下半月板形成的切除術を行ったスポーツ選手26例34膝{男性18例24膝、女性8例10膝、手術時年齢は11歳～51歳（平均23.8歳）}を対象とした。これらの症例に対し、スポーツ種目、スポーツ復帰時期および術前後のスポーツレベル、術後合併症の有無とその対処方法について調査した。なおスポーツレベルについてはTegner　activity　scoreを用いて評価した。
【結果】
スポーツ種目は、サッカーが14例（53.8%）で最も多く、次にテニス3例（11.5%）、ダンス2例（7.7%）と続いた。スポーツ復帰時期は術後7週～18週（平均11.1週）であった。スポーツレベルは、術前のTegner　activity　score 7.6±1.6点が術後Tegner　activity　score 7.6±1.6点であり全例、元のスポーツに復帰していた。術後合併症は、疼痛、関節水腫がスポーツ復帰前1例、復帰後（術後3～6ヵ月）5例に見られた。
【考察】
スポーツ種目でサッカーが53.8%と半数以上を占めていたが、これは当院が横浜の某Jリーグチームの指定病院となっているため患者数におけるサッカー選手の割合が多かったことが要因であると考えられる。スポーツ復帰時期にはばらつきがあるが、両側同時手術例や中高年による変形性関節症性変化（以下OA）を合併しているケースの場合は復帰に時間のかかる傾向にあった。しかし、術後のスポーツレベルは全例で元のレベルまで戻っており、OAを合併していても慎重な後療法を行うことによってスポーツ復帰は可能であることがわかった。またスポーツ復帰を果たしても術後3～6ヵ月で関節水腫を合併する症例が見られたが、ヒアルロン酸の関節内注入と2～3週間の運動制限によって症状は消失した。
【まとめ】
1．スポーツ種目、年齢に関わらず、術後平均11.1週でスポーツ復帰が可能であった。2．全例、元のスポーツレベルに復帰可能であった。3．術後、関節水腫に対しては、ヒアルロン酸の関節内注入と運動制限が有効であった。

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This study was to examine the change of winter sports' image through the broadcast of the Nagano Olympic Winter Games. Before and after the Games, SD-typed investigations were conducted and extracted 5 stable factors for the perception of winter sports. They were interpreted as Dynamism, Beauties, Affinity, Freedom, and Complexity. Most winter sports' impressions tended to be polarized about Dynamism and Beauties after the Games, and Affinity was increased. Further analysis found that there were two types of sports. One is suited for edited broadcasting (eg. figure skating) and the other is suited only for real time or recorded broadcasting (eg. ice hockey)

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　【Purpose】This study was to compare the lower limb joint angles and center of mass （COM） positions measured by Theia 3D markerless and marker-based motion capture systems.【Methods】Sidebox jumps were performed on 9 healthy adults. Ten video cameras for markerless motion capture and 12 video cameras for optical marker-based motion capture were used for simultaneous recording. We compared the lower limb joint angle and the position of the center of mass （COM） of the body from landing on the right platform to taking off【. Results】The relative reliability of the lower limb joint angle was r = 0.59 to 0.99, and the absolute reliability was less than 3.2°. The relative reliability of COM showed a strong correlation of r = 0.97 to 0.99, and the absolute reliability was less than 1.1 cm.【Conclusion】Very similar measurements were made by the two systems, and the use of Theia 3D markerless motion capture system was used not only for walking but also for sports movements such as jumping and landing and in fields that were previously difficult to perform. It is sugested that measurement is possible.

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