エアロビックダンス・インストラクターを対象に, 下肢の形態, アライメント, 関節可動域, 筋力等の個体要因とレッスン時間・内容に注目し, 障害の誘因について比較・検討した.その結果, 以下のような結果が得られた.
A.アンケート調査
1) 被検者全員における下肢の障害発生率は64.3%であった.31才以上の被検者における障害発生率は71.4%であり, また障害経験者の40.7%が指導年数5年以上の者であった2) 障害の種類にはシンスプリント, 足底筋膜炎, 腰痛, アキレス腱炎などがあり, 発生率が最も高かったのは, シンスプリントの29.1%であった.
3) 障害経験群は障害未経験群に比べ, 高強度のHクラスのレッスンを有意に長時間にわたり行っていた.
B.形態
1) 障害経験群の膝蓋骨横幅/大腿骨幅の比は, 障害未経験群に比べ有意に低値であった.
2) 障害経験群の身長当たりの膝蓋靱帯の長さは障害未経験群に比べ有意に高値であった.
C.アライメントおよび関節可動域
障害経験群の股関節の外旋角度は, 障害未経験群に比べ有意に低値であった.
D. 膝 Q angle と Heel touch のEMG
膝 Q angle が正常範囲外の障害経験者における下肢動作中のEMG記録においては, 内側広筋に大きな放電の振幅と iEMG がみられた.
E. 筋力
障害経験群の足底屈筋力の値は, 障害未経験群に比べ有意に高かった.

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本研究は, ラットを去勢し, 睾丸から分泌される男性ホルモンの影響を除外した条件下において, 杜仲樹皮エキスの投与がアナボリックに及ぼす影響について非運動時と運動時を比較検討することを目的とした.実験は32匹, 4週齢Wistar系雄ラットに去勢手術を実施し, 杜仲樹皮エキス投与非運動群 (n=8) , 杜仲樹皮エキス投与運動群 (n=8) , 対照非運動群 (n=8) , 対照運動群 (n=8) の4群に分類した.杜仲樹皮エキスの投与は1g/kg体重の割合で1日1回, 週7回, 4週間にわたって経口投与した.対照群には同じ方法で蒸留水を投与した.運動負荷は, 小動物用トレッドミルを用い, 20m/minのスピードからスタートし, 1週間毎に10m/minのスピードを増加させ, 1日30分間, 4週間にわたって休まずに強制トレッドミル走行を実施した3
結果は次のようであった.
1.副腎比重量において, 杜仲樹皮エキス投与非運動群は, 対照非運動群に比し有意な高値 (p<0.001) を示した.また, 杜仲樹皮エキス投与運動群は, 対照運動群および杜仲樹皮エキス投与非運動群に比し有意な高値 (いずれもp<0.001) を示した.
2.腎臓比重量において, 杜仲樹皮エキス投与非運動群は, 対照非運動群に比し有意 (p<0.001) に増大した.また, 杜仲樹皮エキス投与運動群は対照運動群に比し, 増加傾向が見られたが, 有意な差は認められなかった.
3.肛門挙筋比重量において, 杜仲樹皮エキス投与非運動群は, 対照非運動群に比し有意な (p<0.001) 高値を示した.杜仲樹皮エキス投与運動群は対照運動群に比し有意な (p<0.001) 高値を示した.
4.運動負荷終了後の24時間尿中17-KSは, 杜仲樹皮エキス投与非運動群が対照非運動群, 杜仲樹皮エキス投与運動群の2群に比しそれぞれ有意な高値 (いずれもp<0.001) を示した.杜仲樹皮エキス投与運動群は対照運動群に比し有意な高値 (p<0.01) を示した.また, 対照非運動群は対照運動群に対し, 有意な高値 (p<0.001) を示した.
5.各群の尿中総窒素は, 杜仲樹皮エキス投与非運動群が対照非運動群, 杜仲樹皮エキス投与運動群の2群に比しそれぞれ有意な低値 (p<0.01, p<0.05) を示した.杜仲樹皮エキス投与運動群は対照運動群に比し, 有意な低値 (p<0.05) を示した.
以上の結果から杜仲樹皮エキス投与は, 去勢されたラットの副腎重量の有意な増加をもたらし, 副腎皮質網状層のアンドロゲンの分泌を亢進させ, タンパク同化作用を促進させることが示唆された.また, 運動負荷における副腎皮質網状層の適応能力を増していることが示唆された.

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本研究は大学生女子バスケットボール選手のメディカルチェックにおいて計測した膝関節の前方動揺性と全身の関節弛緩性との関連性を検討したものである.
膝関節靱帯損傷の既往のない大学女子バスケットボール選手34名68膝を対象とした.膝関節の前方動揺性は, MED-metric社製KT-2000Knee Ligament Arthrometerを使用し, 脛骨に201bの前方引き出し力を加えた時の脛骨の前方移動量を測定した.関節弛緩性 (joint laxity score) は中嶋らによるjoint laxity test (全身6大関節+背柱, 7.0点満点) にて点数評価した.
今回の測定によって得られた全被検者の201bの前方引き出し力における前方移動量の平均値は右膝3.8±1.6mm, 左膝3.2±1.5mmであり, joint laxity scoreの平均値は3.2±2.0点であった.前方移動量とjoint laxity scoreの各々の順位相関係数は右膝で0.48 (p<0.01) , 左膝で0.54 (p<0.01) でありともに有意な正の相関関係を示した.
本研究の結果により, joint laxity scoreが高い者は前方移動量の値が大きいことが示された.したがって特別な測定機器を使用することなく簡易に測定することのできるjoint laxity testは, 膝関節前方動揺性が大きい者を検出し, ACL損傷のリスクの高いと思われる者を検出するのには有効な方法であると考えられる.

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本研究は種々の電気泳動法を用いて, 3週間の尾部懸垂によるラットヒラメ筋におけるミオシン分子の変化を詳細に検討した.得られた結果は以下の通りである.
1) 懸垂群ではコントロール群と比べて, HCIの割合が減少し, これまで正常なヒラメ筋で認められていなかった HCIId, HCIIb が発現した.一方, LC の割合には有意な変化は認められなかった.
2) コントロール群のヒラメ筋では SM と IM の2種類のアイソミオシンが認められた. HCIIa から成っていると考えられる IM の移動速度は, 速筋タイプの筋で認められる HCIIa 由来のアイソミオシンのものより遅かった.
3) 懸垂群では SM と IM の2種類のアイソミオシンが認められたものと, SM と IM の他に FM のアイソミオシンが認めれたものがあった. FM を発現していたラットでは HCIId, HCIIb を発現していたにもかかわらず, FM の移動速度は速筋タイプの筋で認められる FM1-3d, FM1-3b に相当するアイソミオシンのものとは異なっていた.
ピロリン酸電気泳動の移動速度は LC と HC の両方に影響を受けるので, 懸垂によって新たに発現した fast type HC の少なくとも一部はミオシン分子として機能していること, さらにこれまで考えられてきた以上に多種のミオシン分子が存在していることが本研究の結果から示唆された.

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The relationships were examined between the relative force level and exertion strategy during rapid isometric contractions. Thirteen subjects exerted isometric pinchings as fast as possible at various force levels. Force curves and surface EMGs from the first dorsal interosseous muscle were obtained during the contractions. While the single-peaked force curves remained analogous up to a certain force level, they changed to multi-peaked ones at higher force levels. The critical force level, which could be determined in all subjects as relative force level to MVC, was positively correlated with the %MVC EMG magnitude for unit time, obtained below the critical level. EMG durations were significantly shorter blow than above the critical level. These results suggest that different exertion strategies are utilized in rapid contractions at different force levels, and that individual differences in the critical force level are related to difference in the manner of motor unit activation.

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Generally, sport players of boxing or football who contact roughly with other players use mouth guard during match or game to prevent the breaking of jow boneor bursting of soft oral cavity. Moreover, mouth-guard are used for the purpose to lighter the load to root of teeth and to improve the skill and power of sport's player.
The purpose of this study was to examine the charactaristic of unfitted by H shape-mouth guard compared to U shape mouth guard.
The following results were obtained.
1. The H shape-mouth guard of this study could reduce the impact to 1/7 level.
2. A relative decrease in ventilation level was shown when H shape mouth guard fitted.
3. With reference to respiratory function, reduction of the amount of oxygen up-take was not observed at heart rate lower than 170 beats/min, and in this case a player feells subjective symptom of stiffing.

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This study was carried out to examine the influence of mouthguards on speech intelligibility. Nine male rugby football players with normal personal occlusion and normal speech served as subjects. All players took the speech intelligibility test while wearing self-adapted mouthguards, custom-made mouthguards and without wearing mouthguards.
The ratio of correct judgments for speech intelligibility wearing self-adapted mouthguards was significantly lower than that of wearing custom-made ones or of not wearing one. When misjudged syllables were evaluated by using the manner of production for articulation, plosives had a tendency to be misjudged as flapped sounds or as other plosives while subjects were wearing self-adapted and custom-made mouthguards. When misjudged syllables were evaluated by the points of production for articulation, bilabials and velars had a tendency to be misjudged as alveolar sounds while subjects were wearing self-adapted and custom-made mouthguards, and alveolar sounds had a tendency to be misjudged as various sounds while subjects were wearing self-adapted ones.
The findings showed that speech intelligibility with custom-made mouthguards was better than with self-adapted ones. Speech intelligibility may be better with mouthguards with reduced palatal thickness than with the current ones because points of prodution for alveolars and velars approach the normal points.

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This study examined the secretion capacity of the gonadal and adrenal cortex systems and the morphology of the adrenal cortex in male rats treated with Tu-chung (Eucommia ulmoides O_LIV) extract, the main component of Tu-chung extract, geniposide, or both agents during exercise load testing.
Twenty-four 4-week-old male Wistar rats were used. The rats were divided into four groups : those treated with Tu-chung extract and geniposide (n=7), those treated with Tu-chung extract (n=6), those treated with geniposide (n=7) and a control group treated with distilled water. The dose of each agent was 0.1 ml/100g body weight. The agents were administered orally for 25 days. For the exercise load test, a treadmill for small animals was used, with a tilting angle set at 0. Exercise load testing was performed for 30 min (2-min warm up and 28-min running) daily for 25 days. The running speed was 20 m/min for the first 5 days, and then increased by 5 m/min every 5 days.
The following results were obtained.
1. The relative weight of the adrenal gland (gland weight/100 g body weight) in the group treated with Tu-chung extract and geniposide was significantly higher than that in the group treated with geniposide or the control group (p<0.01) . The relative weight of the adrenal gland in the group treated with Tu-chung extract was significantly higher than that in the group treated with geniposide or the control group (p<0.01, p<0.001) . Furthermore, the relative gland weight in the group treated with geniposide was significantly higher than that in the control group (p<0.05) .
2. In the group treated with Tu-chung extract and geniposide, the group treated with Tu-chung extract and the group treated with geniposide, the relative gland weight of the testis (testis weight/100g body weight) was significantly higher than that in the control group (p<0.001) . However, there were no significant differences among the three groups.
3. The 24-h urinary excretion of 17-ketosteroid (17-KS) in the group treated with Tu-chung extract and geniposide was significantly higher than that in the group treated with Tu-chung extract, the group treated with geniposide or the control group (p<0.01, p<0.01, p<0.001) . In the group treated with geniposide, the 24-h urinary excretion of 17-KS was significantly higher than that in the control group (p<0.05) .
4. In the three groups treated with Tu-chung extract and/or geniposide, serum testosterone levels were significantly higher than those in the control group (p<0.001, p0.05, p<0.05) .
5. Concerning the morphology of the adrenal cortex, the thickness of the reticular layer of the adrenal cortex was most markedly increased in the group treated with Tu-chung extract and geniposide, followed in order by the group treated with Tu-chung extract, the group treated with geniposide and the control group.
Administration of Tu-chung extract and the main component of Tu-chung extract, geniposide, during exercise load testing significantly increased the weights of the adrenal gland and testis, and promoted testosterone secretion in the adrenal cortex reticular layer and testis.
These findings suggest that geniposide plays an important role in the pharmacological action of Tu-chung.

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