Background: Given that one out of every two Japanese person is diagnosed as cancer in their lifetime, the Second Basic Plans to Promote Cancer Control Programs have prioritized public education and awareness about the disease.

Methods: This study assessed the status regarding recognition of the cancer causes among school students as well as the availability of information on cancer through a nationwide questionnaire survey conducted with 5^th year students in elementary school, 2^nd year students in junior high school, and 2^nd year students in high school.

Results: Responses were obtained from 2,213 elementary school students, 2,960 junior high school students, and 3,703 high school students. Among them, over 90% of students (the highest percentage for a single answer) gave “tobacco,” and around 80% (the second highest percentage for a single answer) gave “alcohol” as causes of cancer. With higher number of school years, the percentage of students giving “genes” as a cause increased, while the relevant percentages decreased for “bacteria/viruses,”　“stress,”　“alcohol,”　“obesity,”　“lack of vegetables,”　“excessive fat consumption,” and “excessive salt consumption.”

　Among students in elementary school, junior high school and high school, over 95% of students (the highest percentage for a single answer) gave “television” as a source of information on cancer. With higher number of school years, the percentage of students who gave “health classes at school” as an answer increased; for male students, the increase in rate was from 21.1% to 62.0% (40.9% increase) while for female students, the increase in rate was from19.3% to 64.3% (45.0% increase).

Discussion: The above results showed that school students had contradictory tendencies; they displayed relatively accurate understanding about some causes of cancer and relatively inaccurate understanding about others. Moreover, the decrease in the percentage of students giving “excessive salt consumption” and other lifestyle-related causes of cancer as answers pointed to a poor situation with regard to improving their lifestyle choices. In contrast, the results suggested that health classes at school were effective sources of information on cancer for students.

Conclusions: Our nationwide survey results suggest information sources and recognition of cancer causes in Japanese school students.

Background: It is important to understand the process of body habitus change during adolescence for the prevention of lifestyle-related diseases such as obesity. The purpose of this study was to evaluate changes of obesity-related indices in university students by using periodic anthropometric measurements.

Methods: The study sample comprised 991 university students (667 males and 324 females) who enrolled in 2002 and became senior year students in 2005 at the C University T Campus (School of Health and Sport Sciences, School of Contemporary Sociology and School of Informatics). We analyzed the associations between the body mass index (BMI) and other obesity-related indices, which are as follows: percent body fat, body fat content, lean body mass, abdominal girth, buttock girth, waist-hip ratio, and waist-height ratio. The measurements at admission were compared to those after three years (at senior year) by using paired t-tests. The associations between BMI differences (i.e.＝senior year value--freshman value) and other indices were analyzed graphically. After classifying the subjects into four categories according to the BMI differences, the differences of each index were compared among the four categories by performing analyses of variance.

Results: During the three years after university admission, the percent body fat, body fat content, abdominal girth, waist-hip ratio, and waist-height ratio increased, and the lean body mass and buttock girth decreased in both male and female students. The result had similar tendencies without distinction of the department. The body fat content difference and abdominal girth difference changed to positive values at negative values (－1.0 to 0) of the BMI difference, and the lean body mass difference and buttock girth difference changed to positive values at positive values (1.0 to 2.0) of the BMI difference. All the indices increased among Subjects in the changed-to-obese group, particularly the fat indices that showed a higher increase when compared to the lean body indices. Among Subjects in the changed-to-non-obese group, all the indices decreased, except for the waist-hip ratio, and the lean body indices showed reductions similar to the body fat indices. The waist-hip ratio increased in all categories of BMI difference. On the basis of the z-scores of the differences, the body fat content showed the highest disparity among the four categories of body habitus change, and the waist-hip ratio showed the least.

Conclusion: Those observed characteristics related each other, and the underlying changes are an increase in fat tissue and decrease in non-fat tissue are basic. It is speculated that the body habitus change, caused by those changes, gradually progresses in university students during that age.

Objective: The purpose of this study was to examine the relationship between extracurricular activities, habitual exercise and academic achievement in junior high school students.

Methods: The subjects were 627 junior high school students (330 boys and 297 girls). The subjects were divided according to their extracurricular activities such as sports and cultural clubs, or no activity. The number of hours per week the student exercises was surveyed by questionnaire. For academic achievement, the cumulative records from five subjects (Japanese, social studies, mathematics, science, English) and four subjects (music, art, physical education, and technical courses or home economics) were used. The academic achievement in each subject was rated on a 5-point scale.

Results: Among the boys, the students involved in sports clubs had higher academic achievement compared to students who were not involved in any extracurricular activities (for the five subjects: sports clubs 16.9±4.4, no activity 14.1±4.5, p＜0.05). Among the girls, students involved in both sports and cultural clubs had higher academic achievement compared to the students who were not involved in extracurricular activities (for the five subjects: sports clubs 18.0±4.1, cultural clubs 19.0±3.9, no association 16.3±4.4, p＜0.05). With age as the controlled variable, positive correlation was shown between time spent playing sports and academic achievement in the five subjects (boys: r＝0.182p＜0.001, girls: r＝0.125p＜0.05).

Conclusions: It was suggested that the academic achievement of male and female students involved in sports clubs was higher than that of students who were not involved in any activity, and there was a positive correlation between habitual exercise and academic achievement.