关于提升长跑的英语作文？

Running is a whole body movement, which enables the body's muscles rhythmic contraction and relaxation, so that muscle fiber

　　Dimension increased, protein content increased. Fit and muscular is one of the symbols.

　　Skeleton is the body of the stent, human activities leverage.

　　In a period of growth and development of young people, adhere to running

　　Step can improve blood circulation, increase the supply of nutrients in bone cells increase bone cell growth capacity, from the

　　And to promote the normal development of the bone.

　　The elderly, reduced metabolism, muscle gradually shrink, and bones appeared back

　　Line of change in bone and joint disease is also increasing.

　　Persist in running can enhance metabolism, delayed bone

　　Degenerative changes, prevention of bone and joint disease in the elderly occur, so that you slow down aging.