近年來因為速食文化、機械及自動化的生活型態的影響，導致現代國小學童過重情形日益增加，因此增加學校體育的體適能活動提高其運動機會以減低其肥胖的情況是學校教育努力的重點項目。本研究旨在探討體重過重（BMI≧25）國小學童參與體適能活動之體位變化成效分析。以方便取樣國小三、四年級學童共33名為研究對象，進行為期6個月之體適能課程訓練（自2010年11月至2011年5月）。以描述性統計及單因子變異數分析過重國小學童BMI值不同性別各時期的變化、過重國小學童不同體位各時期的變化結果。研究結果顯示國小學童BMI值不同性別各時期的變化並無顯著差異，過重學童不同體位各時期的變化也無顯著差異。探究其原因為體適能課程每日參與時間過少及無飲食的控制等因素導致無顯著的差異。但研究發現體重過重之學生整體健康狀況因不同活動狀況和心理健康、家庭狀況而有所差異。建議未來在推動過重國小學童健康體位策略時，應鼓勵學生多從事中等以上費力的身體活動及養成良好的健康飲食習慣，不僅是在學校中實行，同時也需針對其家中飲食習慣進行調整。

　　In recent years, since the impact of fast-food culture and lifestyle of machinery and automation that led to modern elementary school students have overweight problem were increased, therefore increasing physical fitness activities curriculum to improve their sporting opportunities may best way reduce their obesity and overweight problem. The purpose of this study was to investigate the body composition change of overweight and obese students (BMI≧25) take part in fitness active in elementary school. 33 4th and 5th grade students were selected to participate in the program for 6months (since 2010.11to 2011.05). Descriptive statistics and ANOVA analysis of overweight BMI of elementary school children of different genders at different stages of change, overweight elementary school children of different positions at different stages of changes in the results. The results showed that elementary school children's in BMI and body position were no significant different during this period. For this result shows that may during that fitness actives time too short for everyday, also the diet need to control in this period. Another research result shows that these students in this study were vary by their activities, family lifestyle and mental health status. In feature study suggestion for overweight physical fitness activities curriculum, that can encourage their more moderate exercise and healthy diet habited in school and family life.