Mechanical loading through exercise builds bone strength

Oct 5 2004

Mechanical loading through exercise builds bone strength and this effect is most pronounced during skeletal growth and development, according to Charles H. Turner, professor in the Department of Orthopaedic Surgery and director of orthopaedic research at the Indiana University School of Medicine, Indianapolis.

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.