4Akima H, Kano Y, Enomoto Y, et al. Muscle function in 164 men and women aged 20-84 yr[J]. Med Sci Sports Exerc, 2001, 33(2): 220-226.
5Hamrick M W, Samaddar T, Pennington C, et al. Increased muscle mass with myostatin deficiency improves gains in bone strength with exercise[J]. Bone MinerRes, 2006, 21(3): 477-483.