Under revisions made to school curriculum guidelines in 1989, the terms “male and female” (or “boy and girl”) were eliminated from elementary, junior high, and senior high schools, and institutional discrimination on the basis of gender was eliminated. Nonetheless, it is believed that existing gender bias has a significant impact on the behavior of instructors and students. In order to verify this, we conducted a survey of junior high schools in four prefectures to the west of the Kanto region concerning the gender of health and physical education instructors, the percentages of male and female instructors for each sport, and the events held for boys and girls in school athletic meets (sports days) with the intention of determining their characteristics. The research method consisted of a written questionnaire distributed by mail to all public and private junior high schools in Kanagawa, Aichi, Okayama, and Hiroshima Prefectures. The survey was conducted from September to December 2003, and valid responses were received from 634 schools (47%). The survey results indicated that female health and physical education instructors account for about 30% of the total. The results also indicated a strong tendency for female instructors to instruct in dance and male instructors in the martial arts. These gender differences were particularly prominent in the events conducted during student field days. More than 60% of the schools hold events limited to just girls or boys. In track and field events, girls' race events were for shorter distances. Group events also showed an awareness of gender differences, with girls participating in dance while boys participate in cavalry battle games and stunt-type events. The survey results indicated that existing gender bias remains strongly rooted in the field of education.

抄録全体を表示

　近年，スポーツ選手のエネルギー不足に関する研究が国際的に盛んに行われている。スポーツ栄養で使われる「エネルギー不足」とは，負のエナジーバランス状態を指しているわけではなく，エナジーアベイラビリティー（energy availability: EA）が低下した低EAの状態を指している。EAとは，エネルギー摂取量からトレーニングによって消費されるエネルギー量を差し引き，除脂肪量で除したものと定義されている。スポーツ選手が低EAの状態に曝されると，スポーツにおける相対的エネルギー不足（relative energy deficiency in sport: REDs）の国際コンセンサスに示されているさまざまな兆候や症状を引き起こすことが報告されている。慢性的な低EAにより，多くの生理機能が影響を受けることになる。例えば，甲状腺ホルモンや性ホルモンが低下し，コルチゾールが上昇するなど，内分泌の攪乱が起こる。そのため，エネルギー代謝が抑制されて安静時代謝量が低下する。女性選手では無月経を含む月経異常を引き起こし，男性でも性腺機能の低下など，性別を問わず生殖機能の低下を招く。骨形成の減少と骨吸収の増加によって骨密度が低下し，疲労骨折を引き起こしやすくなる。これらを早期発見し予防するためには，EAの代理マーカーの変化を含めて，栄養アセスメントの結果導かれた課題と関連する項目をモニタリングしていくことが極めて重要であり，スポーツ現場でのスポーツ栄養士／管理栄養士の役割は大きい。

抄録全体を表示

 The purpose of this study was to clarify the characteristics of the vaulting motion of world-class female pole vaulters in comparison with male pole vaulters at the same vaulting performance level. The vaulting motions of 11 world-class female pole vaulters (FW group, records: 4.50—4.80 m) and 8 male pole vaulters who had records similar to the FW group (MV group, records: 4.40—4.80 m) were analyzed using three-dimensional motion analysis. The phase from one step before take-off to vaulting over the crossbar was analyzed.
 The FW group had the following characteristics.
 (1) Body weight was lower than that of the MV group.
 (2) The run-up and take-off velocities were slower than those of the MV group.
 (3) The distance between the top grip (right hand) and the lower tip of the pole was shorter than that of the MV group.
 (4) At take-off, the center of gravity was higher, and the pole angle relative to the ground was larger, than in the MV group.
 (5) In the pole bending phase after take-off, the shoulder flexion angle and the knee extension angle of the take-off leg were larger than in the MV group, thus increasing the moment of inertia of the body. Therefore, early backward tilting of the trunk was restricted.
 (6) In the pole straightening phase, the pole was extended earlier than in the MV group owing to the rapid extension of the shoulder joint and the rapid swing of the trunk.
 (7) At pole release, the body was in a more vertical position than in the MV group.
 These findings suggest that whereas the vaulting motions of the FW group were superior to those of the MV group, run-up velocity and pole length of the former were inferior.

抄録全体を表示

A longitudinal design was used to study the development of sprint performance in eight first-class male sprinters from the age of 12 to 15 years. Measurements were performed annually every November for sprint speed, step frequency, step length, sprint motion, and isokinetic peak torques during knee extension and flexion. Furthermore, attempts were made to analyze support time and non-support time, angular kinematics, and isokinetic peak torques at 60, 180, 300 deg/s. The results obtained were as follows : 1. At the ages of 12 and 13 years, mean values of body height and weight were larger for the subjects than for normal Japanese boys. However, at the last measurement at the age of 15 years, no differences were found between them. The skeletal age of the subjects was about 3 years more advanced than chronological age at 12 years. These data therefore, confirmed that the subjects showed an earlier growth spurt. 2. From 12 to 14 years of age, sprint speed increased significantly from 8.79 m/s to 9.61 m/s. From 12 to 13 years of age, step length increased significantly from 1.95 m to 2.08 m. However, no significant increases in step frequency were observed with age. From 12 to 13 years of age, the improvement of sprint speed resulted from the increase in step length rather than step frequency. 3. Significant increases were seen in maximal thigh lift velocity (ωT) from 12 to 14 years of age and in maximal leg swing velocity (ωL) from 12 to 13 years of age. However, no correlations were found between the increases in sprint speed and those of all sprint motions such as maximal leg swing velocity from 12 to 15 years of age. 4. From 12 to 13 years of age, isokinetic peak torques during knee flexion (angular velocity; 60, 180, 300 deg/s) showed significant increases. From 12 to 15 years of age, increases in sprint speed were significantly correlated with those of isokinetic peak torque during knee flexion at angular velocities of 180 and 300 deg/s. For all ages, significant partial correlations were found between sprint speed and isokinetic peak torque during knee flexion at angular velocities of 180 and 300 deg/s. 5. In spite of the fact that one subject (IK) showed better sprint performance than another subject (NI) at the age of 12 years, the latter subjects was able to perform better than the former at the age of 15 years. This change was due to the larger increase in body height and weight as well as the greater development of isokinetic peak torque during knee flexion in NI than in IK. 6. The relationship between the increase in sprint speed and skeletal maturity indicated that the increase in individuals who were skeletally immature after the age of 12 years were greater than those in individuals who matured early.

抄録全体を表示