本研究以運動參與行為當干擾變項，以探討國小學童之健康體適能對學業成就的影響，研究結果將提供行政單位參考。研究對象以臺中市某國小100學年度5、6年級學生為母群體，採全面抽樣，共取得有效問卷543份，測驗所得資料以SPSS for windows18.0套裝統計軟體處理，以描述性統計、交叉分析、皮爾森積差等統計方法找出變項之間的關係，再以階層多元迴歸分析體適能對學業成就的預測解釋力，並以運動參與行為作為干擾變項的預測情形，顯著水準定為α=.05。結果發現：一、國民小學高年級學童在健康體適能對學業成就具有部份預測能力。健康體適能之BMI 值能負向影響學童學業成就，表示學童之BMI 值愈高，身體組成愈差，學業成就表現愈差。健康體適能之坐姿體前彎能正向影響學童學業成就，坐姿體前彎成績愈好，愈能正向影響學童學業成就。二、國民小學高年級學童運動參與行為在健康體適能對學業成就具有部份干擾效果。學生參與運動頻率與運動持續時間愈長，學生學業成就的表現愈好；學生之運動參與行為表現愈好，學生學業成就表現愈佳。

The purpose of this study was to explore the impacts of physical fitness lessons on elementary school students' academic performances, in which the behavior of sports participation is treated as an impact factor. Participants were the fifth and sixth grade students in the 100th academic year the Elementary School in Taichung. Surveys were conducted through comprehensive sampling, and a total of 543 questionnaires were collected as valid data. Descriptive statistics are done by SPSS, cross analysis, and Pearson correlation methods to identify the relationship between the variables. Hierarchical multiple regression analysis was used to explain the predictions of the relationships between components of fitness and academic achievements. The behavior of sports participation acted as an interfering variable of the prediction. The result of the study was concluded as follows: Firstly, there is a partly predictable relationship between health fitness and academic achievements of Grade five and grade six students in Elementary School. BMI values of physical fitness showed a negative connection with students' academic performances, which meant the higher BMI value (worse body composition), the worse the academic performance was. The ability of doing seated forward bend was positively connected with students' academic performances, which meant those who could reach farther while they sat and bent forward scored better academically. Secondly, sports participation behaviors of grade five and grade six students in Elementary School showed a moderate effect on their academic performances. Students who participated longer and more frequently in sports, achieved better scores academically. Students who performed better in sports also tended to have better academic performances.