What kind of exercise should be used to treat
osteoporosis?
Moderate- to high-intensity weight-bearing aerobic exercise,
high-intensity progressive resistance training and high-impact
loading (such as jumping) increase BMD (primarily in the spine)
by an average of 1% in pre- and postmenopausal women,51,52
whereas exercise such as low-moderate intensity walking alone
has inconsistent effects on preservation of bone density.53 By
contast, significant benefits of exercise for the femoral neck
are not proven.54 More robust exercise interventions appear to
produce greater effects. Inclusion of weight-lifting and balancetraining
exercises should provide the widest range of benefits
relevant to fracture protection, as well as reducing muscle
weakness, falls risk and depression, and increasing muscle mass
and mobility. Whether these benefits translate into hip fracture
reduction is currently unknown, but it is reasonable to use
exercise for risk factor modification pending completion of
such studies.
Although there are still many unanswered questions with regard
to the optimal prescription of exercise for bone health, and in
particular its ultimate efficacy for hip fracture prevention, there is
evidence that bone responds positively to novel mechanical forces,
with rapid, short bursts of high intensity loading more effective
than sustained, low intensity loading. For example, jumping is
more stimulating to bone cells than sustained, low impact activity
such as walking.
Although weight-bearing aerobic exercise, high impact training,
and resistance training have all been shown to maintain or
augment bone density in this stage of life, resistance training has
the added benefit of increasing muscle mass and strength, as well
as balance. This combination of effects on body composition and
muscle function is a direct antidote to age-associated changes
in these domains, and offers potential benefit for many health
conditions in addition to osteoporosis. Aerobic exercise does not
increase muscle mass and strength, and does not improve balance,
and is therefore less comprehensive in its effects on the multiple
risk factors for osteoporotic fracture. Additionally, there is no
evidence in young women to support the isolated use of aerobic
training that does not involve high impact forces as a means to