But even evidence in adults suggest that you don't have to do that much for it to be adequate stimulus. And even in our Asian population they were significantly less active because culturally there's differences. After school, they would go to English classes, or they would go to their violin lessons, or they would take extra math classes, so they weren't as active. And there was a significant difference between these children in terms of the amount of bone they already had in 5th grade, based on activity and to some extent, calcium. What you do in childhood is probably your best prevention for osteoporosis in adult life.
Research tends to focus on senior population and it's already too late.
They just have to be active. Oh golly, I didn't do enough physical activity when I was young in the critical time of bone growth. I think if I were giving out that message. Conservation is as important. So the three parts, the three sort of determinants of a healthy skeleton are gain during childhood, conservation during adulthood and the loss and the rate at which you lose bone during later adulthood, conservation is key as well.