Serum osteocalcin, or bone Gla protein, reflects osteoblastic activity (Liu and Peacock, 1998) and is a sensitive and specific marker of bone formation (Gundberg et al., 2012 and Szulc et al., 2000). The concentration of osteocalcin increases during high bone turnover and decreases during low bone turnover (Szulc et al., 2000). C-terminal telopeptide of type I collagen (CTx) is a marker of bone resorption, and reflects the rate of bone loss (Delmas et al., 2000). CTx increases when bone mass is rapidly lost