Bone mass in puberty

: Bone mass increases as the pubertal sex hormones secretion increases, and it reaches a peak of a maximal bone mass at approximately the age of 18 years in females and 20 years in males. We developed standard values for speed of sound (SOS) with ultrasonic measurement of the tibia in children and adolescents, a method to assess cortical bone. As a result, SOS of the tibia increased in an age-dependent manner in both sexes. The maximal increase was observed approximately 1 year after the age of peak height velocity, which was reported to be 11 years and 13 years in females and males, respectively. During the time when body height increases rapidly, there is a period of relative bone fragility in which bone strength gain is delayed against an increase in length of tibia. Appropriate physical activity and nutrient intake during puberty can have an excessive influence on the health of bone.