Higher muscle mass, not fat mass, leads to healthier bone development in children, suggests a new research.

"These findings point to the importance of early childhood physical activity to optimise muscle and bone growth," said lead investigator of the study Rebecca Moon from the University of Southampton.

For the study, detailed measurements of 200 children enrolled in the Southampton Women’s Survey were taken soon after birth and then again at ages six to seven years old.

They assessed bone mineral density, shape and size of the tibia (the shin bone), and body composition and found a link between the amount of lean muscle and healthy bone development.

"Bone strength and size is important because they are significant factors in long term osteoporosis and fracture risk," Moon said.

A ten percent increase in peak bone mass will delay the onset of osteoporosis by 13 years, Moon added.

The team also found that the relationship between changes in lean muscle and bone development was stronger in girls than in boys, despite the ages of the children ruling out the onset of puberty as a factor.

The study was published in the journal Bone.