The Influence Of Intensive Jump Training On The Formalogy And Intensity Of Thighbones Of The Rats In Gowth

The experiment was to imitate the high-intensity training by means of jumping the rats in the period of growth, and the comparison of results of different training quantity was made to discuss the influence of high-intensity training on the shape and intensity of adolescent bone,to provide the theoritic reference to choise the reasonable training intensity and quantity for the training of adolescence.28 male rats were devided equally into 4 groups: comparative group, jumping group A (Ja group, 50 times/day), jumping group B (Jb group,100 times/day), jumping group C (Jc group, 200/day). Training of rats is in the box that was made for rat jumping. The height of jumping was 2. 3 times as much as the height of rat, and the frequency of jumping is 10 times/m, 6 days/week, 8 weeks. At the end of training, the rats were put to death and the thighbones were taken out, the length of which were measured. By means of NORLAND XR-26 DXA, the BMC, AREA, BMD of rats were measured, and by means of SHIMADZU AG-20KNA to give three point bend experiment to the thighbones of rats, and the instrument of painting recorded the curve of load-deform automatically. The cross section of broken thighbones were taken into micrograph and made into slides of cross section of bone, which then were projected on the digital pad to be analyzed, and then the parameters of cross section of thighbones were calculated by the program that had been made before experiment. At last, the indexes of mechanics of materials of bone were calculated. The data got from the experiment were analyzed by ANOVA in SPSS6. 0.Under the condition of this experiment, after 8-week training the growth of vertical axis of rats' thighbone got restrained, and more the training quantity is , more significant the effect is. The growth of cross axis was not influenced signicantlly. The BMC of rats' thighbone dropped, and more the training quantity is , more significant the effect is. The BMD of rats' thighbone was not influenced significantlly. The result that the quality of bimechanics of rats' thighbones was changed showed that, the ability of rats' thighbones resisting sabotage and deformation was reduced, and the fragility was more significant and the intensity of bone was reduced, and more the training quantity is , more significant the effect is.These results showed that, the heavy-intensity training the experiment took made the mechanics stress the rats got higher than the rats' physiological range and thus the growth of vertical axis of rats' thighbone was restrained and the content of bone minerals reduced. The reason that the fragility of rats' thighbones became more significant may be the long-period excessive mechanics stress, which destroyed bone molecules and made the micro-structure of bone, by the adjustment of nervors-body fluid mechanism, the composition of bone was changed and the the content of BMC declined, which made the structrual and mechanical tenacity of rats' thighbone declined and the quality of bone also reduced.Conclusion: the results of this experiment show that it is not appropriate to adopt heavy-intensity training in the adolescent sport training, and if it is necessary to adopt the heavy-intensity train the training quantity must be controlled appropriately to avoid influencing the growth of bones and making the intensity of bones reduced.