Effect of endurance training on bone quality in growing rats

• Main Authors: Ming-Yao Chang, 張明曜
• Other Authors: Tsang-hai Hang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/18155610843140293625

碩士 === 國立成功大學 === 體育健康與休閒研究所 === 97 === Purpose: The aim of the study was to investigate the effects of endurance running on the bones quality. Methods: Forty-eight male Wistar rats (7 weeks old) were randomly assigned into four groups, which were control group (CON, n=12), high intensity running group (HIGH, n=12), low intensity running group (LOW, n=12), and diet control group (DCON, n=12). Animals in the HIGH and LOW groups underwent endurance training at speed of 15m/min~28m/min and 12m/min~22m/min, respectively, on the treadmill 5 days per week for 8weeks. To match the body weight gain of the exercise group, the DCON rats received mean quantity of chow consumed by exercise groups. Three days after the end of 8-week training program, all animals (15 weeks old) were killed under deep anesthetization. Blood and bone samples were collected and stored for further serum marker assay, tissue dynamic histology analysis, collagen organization of bone matrix and micro-CT 3D analysis. Result：After an eight-week exercise training, body weight gain was significantly higher in the CON group as compared with other three groups. Bone metabolism markers showed no difference among four groups. In the DCON group, serum calcium, phosphorus, and IGF-I concentration were significantly different to other three groups. Furthermore, corticosterone was marginally higher in the DCON groups (p=0.057). The femur length, cross-sectional area, dry weight was higher in the CON group as compared with another three groups. And, CSMI of the CON group was significantly higher than the LOW group (p＜.05). Additionally, the CON group showed a significantly higher wet weight in femora. In biomechanical test, yield load and fracture load was higher in the CON group as compared with the LOW group. In tissue material properties level, no difference was shown among the groups. Dynamic histomorphometry and bone collagen organization showed no significant level among groups. Conclusion: The study showed that the eight weeks endurance running showed no negative effects on bone quality；Calorie control diet in purpose of matching body weight between exercise and control animals might negatively influence normal bone development.