Iron deficiency state are frequently observed in boy students of senior high school, especially in those who were actively engaged in sports after school. This has become an important problem in terms of athletic medicine and health in students. Here we examined hematological findings in boy students who belong to sport club in a public senior high school in Sapporo. Moreover, their physical status and general activities were analyzed by questionnaire. Several conclusions obtained were as follows:
　1) The red cell count, the hemoglobin level, the white cell count and the platelet count were all within normal limit.
　2) Serum iron level in the first grade students was significantly lower than that in the further grade students.
　3) Total iron-binding capacity level in the first grade students tended to be higher than that in the further grade students, but not significant.
　4) Serum ferritin level in the first grade students was significantly lower than that in the second grade students.
　5) Low serum iron level was observed in 17.5, 8.7 and 42.9% in each grade tested respectively, and most of them belonged to the first grade.
　6) According to Multivariate Statistical Analysis by the Method of Hayashi's Surgo II, students with low serum iron level showed less physical activity and lowered power of intellectual concentration. Moreover, they appeared to need longer sleeping time as compared with students with normal serum iron level. When students with low serum ferritin level were compared with students with low serum iron level in terms of spending time for sports, it was found that the former used a little longer time for it. It might be suggested that most of them noticed their decreased scholastic ability.

DESCENTE SPORTS SCIENCE Vol.5/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE