目的：在評估六週中等強度密集性慢跑訓練對肥胖者減重後體組成及免疫系統的影響。方法：受試者為18名，BMI(Body Mass Index, BMI)>25以上之大專女學生。全體受試者在不改變飲食的狀態下，實施每週5次，每次40分鐘，運動強度介於50%-70% HRR(下標 max)的慢跑訓練。並於訓練前24小時及訓練後48小時各接受一次體重、身體質量指數、腰臀圍比、體脂肪百分比測量及總膽固醇(TC)、三酸甘油酯(TG)、高密度脂蛋白膽固醇(HDL)、低密度脂蛋白膽固醇(LDL)和白血球、淋巴球等血液生化數值檢定，藉此觀察體組成及免疫功能的變化情形。所得之數據是以平均數標準差表示，並以配對樣本t考驗分析訓練前後的差異，顯著水準訂為p<.05。結果：（一）體組成方面：體重、身體質量指數、體脂肪百分比、三酸甘油酯上呈現明顯的下降(p<.05)，且在高密度脂蛋白膽固醇上呈現明顯的上升(p<.05)。而在腰臂圍比、總膽固醇及低密度脂蛋白膽固醇上未達顯著改變。（二）免疫功能指標：雖在白血球數量呈現明顯的增加(p<.05)，但在淋巴球數量呈現明顯下降(p<.05)。結論：本研究主要的發現為六週中等強度的慢跑訓練對肥胖者改善體組成上，可獲得正面的訓練效果。但其訓練後淋巴球數量減少的現象，可能是過度訓練或是訓練頻率過於密集所產生免疫系統抑制的現象，其對減重者身體健康的影響程度為何，仍待進一步評估。

The main purpose of this study is to evaluate the effect of a six-week mid-intensity of intensive jogging training on body composition and immune system of over-weighted persons. The participants were 18 over-weighted female college students (age: 17.82±0.63 yr; height: 156.36±3.32 cm; weight: 64.52±2.48 kg; BMI 26.33±0.60 kg/m^2). All participants were designated to three jogging training groups; the exercise intensity was varying from 50% HR(subscript max) to 70% HR(subscript max). All subjects completed 40 minutes jogging training, 5 times a week for a consecutive six weeks. The biochemical parameters were collected at 24 hours before and 48 hours after the training period. Those parameters included body weight, height, WHR (waist-to-hip circumference ratio), percentage of body fat, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and numbers of leucocytes and lymphocytes. The difference between parameters was determined by pair t test and the statistical significance was set at P=.05. The results showed that (1) body weight, BMI, percentage of body fat, and TG decreased sharply (p<.05), while HDL increased significantly (p<.05). There were no difference in WHR, TC, and LDI. (2) the number of leucocytes increased apparently (p<.05), while that of lymphocytes decreased dramatically (p<.05). We concluded that the six-week mid-intensity of intensive jogging training would make positive effects on improving the body composition of obese persons. However, further investigation such as whether the training might suppress the immune system and affect health of the weight reduction persons is needed.