Exercise for a long life
An exciting report from the University of Washington in
Seattle shows how exercise prolongs lives (Exercise and Sport
Sciences Reviews, April, 2007). The leading theory for aging is
that mitochondria produce oxidants that damage the DNA in cells
to shorten life. Mitochondria are parts of cells that convert food to
energy. They function by stripping off electrons and protons from
food to produce energy. When they do this, they end up with free
electrons that eventually attach to oxygen, which produces free
radicals that stick to genetic material in cells to cause permanent
damage.
As you age, your muscles lose mitochondria and those
that remain become smaller so that they produce far more free
radicals. Anything that increases the size or number of
mitochondria makes them function more efficiently so they
produce fewer free radicals. This recent review shows that
exercising as you age actually prevents loss of mitochondria and
can even make them larger so they produce fewer oxidants.
This report is particularly significant because a recent
survey of the world's literature in the Journal of the American
Medial Association (February 28, 2007) showed that there is little
evidence that taking antioxidant supplements prolongs life, and
they may even shorten life. Apparently it is necessary to avoid
production of oxidants, not just to take antioxidants as a corrective
measure. On the basis of these studies, if you do not already
have a regular exercise program