By Gretchen Reynolds, New York Times

Active older people resemble much younger people physiologically, according to a new study of the effects of exercise on aging. The findings suggest that many of our expectations about the inevitability of physical decline with advancing years may be incorrect and that how we age is, to a large degree, up to us.

Aging remains a surprisingly mysterious process. A wealth of past scientific research has shown that many bodily and cellular processes change in undesirable ways as we grow older. But science has not been able to establish definitively whether such changes result primarily from the passage of time — in which case they are inevitable for anyone with birthdays — or result at least in part from lifestyle, meaning that they are mutable.

This conundrum is particularly true in terms of inactivity. Older people tend to be quite sedentary nowadays, and being sedentary affects health, making it difficult to separate the effects of not moving from those of getting older.

In the new study, which was published this week in the Journal of Physiology, scientists at King’s College London and the University of Birmingham in England decided to use a different approach.

They removed inactivity as a factor in their study of aging by looking at the health of older people who move quite a bit.

Read the whole story