Effects Of Jump On The Indexes Of Bone Histomorphometry And Bone Biomechanical Properties Of The Growing Period Mouse

Lots of literature reported the growth of bone in growing period is important to one's whole life. As the storeroom of bone mass, the peak bone mass is correlated with the probability of osteoporosis. So it is very important for the peak bone mass and bone health when grown up to obtain more bone mass in growing period.As an inexpensive and convenient means for health gaining, exercise has been attached more importance by people. The study on bone and exercise have indicated that taking more exercise in growing period can boost one's bone growth, increase one's bone mass, and improve one's structure and biomechanical properties of bone. And more and more studies have indicated that the effect of exercise boosting bone mass increasing is more distinct in growing period, and the exercise of adult can mostly maintain bone mass or reduce bone mass loss. So the adolescent in growing period should take more exercise to boost their bone growth and improve their bone health when grown up. Then what is the best kind of exercise to improve our bone health? And what are the results of different exercises in improving our bone health? The contrast study on this aspect is still little, and some study result may conflict with each other, so it is necessary to study further.At present, the methods adopted in the researches on bone growth and metabolism include molecular biology, biochemistry, tectology, the measure of bone mineral density, and biomechanics. With regard to exercise and bone health, most researches merely focus on ordinary description of bone mineral density and metabolic symbols, few has done on synthesize research about bone mineral density, bone microstructure and biomechanical properties, this greatly limits the study on prevention and treatment of osteoporosis. ObjectiveWe contrast the effects on bone growth between swim group and jump group in order to find reasonable exercise form for bone health. methodHaving succeeded in building up a jump training model, we divided randomly eighteen 4-week SD male mice into three groups: control group (N, n=6), swim group (S, n=6), jump group (J, n=6). After 8 weeks of training, bone mineral density, bone histomorphometry index and bone biomechanical properties of the mice were measured. resultThe swim group has a higher lumbar BMD as compared with the control group, there was no difference in the femur BMD between the swim group and the control group. The jump group has a higher lumbar BMD and femur BMD as compared with the control group.There was no difference in the bone histomorphometry indexes of tibia between the swim group and the control group. The jump group has better bone histomorphometry indexes of tibia as compared with the control group.The swim group has better indexes of lumbar bone biomechanical properties as compared with the control group, there was no difference in the femur biomechanical properties between the swim group and the control group. The jump group has better lumbar biomechanical properties and femur biomechanical properties as compared with the control group. conclusion1. 8 weeks of swim training increased the bone mineral density and biomechanical properties of the lumbar of mice greatly, but the swim training have little effect on femur and tibia of the mice.2. 8 weeks of jump training increased the bone mineral density and biomechanical properties of the lumbar and femur of the mice greatly, and the jump training has obvious effects on bone histomorphometry index of tibia too.3. There are body part differences of the effects on bone metabolism of different exercise forms.4. Bone mineral density is remarkable correlated with biomechanical indexes, such as maximum of load, elastic load, maximum of stress, elastic stress, rigid coefficient, Young's modules and energy absorption. And the correlativity is bigger in bone mineral density and material mechanics indexes than in bone mineral density and structural mechanics indexes. Bone mineral density is negative correlated with deformation and strain.5. The mouse jump training model is a good strength training model for animal, it is very useful in the study of bone metabolism and exercise and the study which correlated with animal jump training.