高校1年生の心電図所見と中学時代の運動歴との関係

Influence of Exercise during Junior High School on ECG Findings among Senior High School Students

要旨　高校1年生の学校心電図検診所見と中学時代の運動習慣の有無との関係を検討した．学校心電図検診時に，質問紙による中学時の運動習慣に関するアンケート調査を行い，心電図所見とアンケートの回答が得られた5,742名(男子2,626名，女子3,116名)を対象とした．アンケート調査より中学時に「運動クラブに選手として所属し」「週に6日以上の活動を行い」「“きつい”以上の運動強度で行い」「友人より多い運動量であった」の4項目すべてを満たした者を「高運動群」，それ以外を「低運動群」とした．中学時代「高運動群」の主な心電図上の変化は心拍数の減少であった．また，「高運動群」で有意に多い心電図所見は不完全右脚ブロックと上室性期外収縮であった．

　Electrocardiographic (ECG) findings of senior high school students were studied in regard to the influence of physical and athletic activities during junior high school. The quantity of exercise was reported previously by questionnaires in 5,742 students (2,626 male and 3,116 female) as follows: 1)Regular athletic players, 2)training more than 6 days/a week, 3)self-motivation train hard and 4)training harder than colleagues. We categorized the students who fitted all four items as the high exercise group. The other students were categorized as the low exercise group. The ECG findings of the high exercise group show significantly slower heart rate (long R-R interval), incomplete right branch block and supraventricular arrhythmia compared with the same factors in the low exercise group. The present study suggested that incomplete right branch block without any heart diseases in senior high school students is due to high exercise during junior high school days.