Prevalence of iron deficiency among university kendo practitioners in Japan: an observational cohort study

Background Iron deficiency is widely recognized as being the cause of anemia in athletes, although iron status in athletes of Kendo, a traditional Japanese martial art based on swordsmanship and practiced as an educational sport, has not been widely investigated. Methods We performed a health assessment on anemia and serum ferritin levels, along with nutrient intake evaluation, for Kendo practitioners in a university in Japan. Results A total of 56 Kendo practitioners (39 male and 17 female) aged between 18 and 23 years participated in the study. No individuals exhibited WHO-defined anemia (less than 13 or 12 g/dL of hemoglobin levels in male or female), while hypoferritinemia (less than 30 ng/mL) was found in seven (41%) females but not in males. Significantly higher body mass index was found in the female athletes with hypoferritinemia compared to females with normo-ferritinemia in sub-analysis (median [interquartile range]; 25.6 [24.2, 26.9] versus 22.6 [21.7, 24.1], respectively. p < 0.05). No significant differences in the intake of iron were registered between males and females (with and without hypoferritinemia) using data from a food-frequency questionnaire survey. Conclusion No apparent anemia was found in adolescent Kendo practitioners, although this study confirmed the presence of hypoferritinemia in several female athletes. Careful follow-up, involving both clinical and nutritional assessment, will be necessary for them to prevent progression into anemia. A future study with larger cohorts in multiple sites is warranted to assess the prevalence of iron deficiency for validation and, if necessary, to devise a strategy for improving the iron status in Kendo athletes

ジュギョウ ホウコク セイカ タイイク シュウチュウ ジツギ ボウリング ニ オケル ジュギョウ テンカイ ニ カンスル ケンキュウ

The purpose of this study was to examine achievement degree of learning objective of students paticipated in the bowling class and to assess the class process. 54 students participated in the class that was done in five days during the summer vacation. The class process was basically composed by a lecture, technical practice and game(Table.1). On second day, individual technicak instruction for all the students was done by recording bowling throwing motion video. In addition, a questionnaire about conscionsness of the bowling and the evaluation of the class process was distributed the students on final day. The results obtained were summarized as follows; 1) In the bowling game, the average score and the average high score increased. 2) Change in the high score of the students was divided into three types, i.e. ascending and fluctuation types shown the score improvement and descending type. Also, the plateau of the score was showed in 60% of the students in forth day and/or fifth day of the class. The main factors of the score improvement were a series of the fundamental and subject practices, the individual student instruction used VTR and the instruction by professional bowler. On the other hand, the score descent and plateau were caused by too many throwing frequencies, lack of the rest time and mental weakness. 3) Consciousness of the students for the bowling changed from play to sport through the lecture. 4) From the questionnarie about the evaluation of the class process, the students showed a feeling of satisfaction for the class process through the acquirement of the skill, theory and manner of bowling, and then the posture which tried to enjoy the bowling as one of long-life spots. These results indicate that the learning objective of the bowling class was mostly achieved through the class process, and adjustment of the throwing frequency, securing of the enough rest time and the mental training is required in the future class process