Exercise that puts the "best" kind of mechanical load to strengthen bones, especially during childhood and adolescence, Turner says, involves impact or high rates of load such as running or jumping, as opposed to swimming or biking. Growing bones are most responsive to the strengthening effects of running/jumping, which have the additional benefit that these types of exercise don't affect longitudinal growth, Turner says.
Activities like "serious weight-lifting, however, aren't recommended for children because overloading growing joints can stunt longitudinal bone growth," and consequently stunt overall limb growth and height, he adds.
Turner says that the strengthening effect of exercise is very efficient because the cellular mechanosensors within bone direct osteogenesis (new bone growth) to where it is most needed to improve bone strength and hence bone mass.
Editors note: Turner is reporting his findings at the American Physiological Society's 2004 Intersociety Meeting, "The Integrative Biology of Exercise," Oct. 6-9 in Austin.
The schedule for the exercise meeting can be found at (http://www.the-aps.org/meetings/aps/austin/tentative.pdf). The complete program, including abstracts, for the entire meeting is available upon request to members of the media.
Arrangements for on-site interviews, or telephone interviews during the meeting can be arranged through APS Communications Officer Mayer Resnick (cell: 301-332-4402, firstname.lastname@example.org) or through Stacy