Osteoporosis has been established as a major public health problem, primarily effecting
women. The attainment of maximal peak bone mass is crucial in the prevention of
osteoporosis, yet little is known about the specifics of bone accrual. Physical activity
has been identified as an important modifiable factor controlling bone accrual. It is has
been shown that increased activity during peri-pubertal years increase bone mineral content
during adulthood. Thus, strategies designed to increase peak bone mass should target the
peri-pubertal years of critical bone acquisition.
Hypothesis 1a: The amount of bone mineral accrued during the peri-pubertal years is greater
in girls who engage in impact activity than in those who do not.
Hypothesis 1b: The positive effects of impact activity on bone accrual are maintained after
cessation of the activity, resulting in greater bone mineral density in girls who
participate in impact activity during a portion of the peri-pubertal years than in those who
never participated in impact activity.
- Subjects between the ages of 10-12 will be asked to participate