Exercise decline and aging: chickens and eggs


As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)


I just noticed a new paper in the Journal of Sport and Exercise Psychology by University of Ottawa prof Bradley Young and his collaborators, who have produced a series of interesting studies on masters athletes. In this case, they were looking at the lifetime training of competitive 10-kilometre runners between the ages of 40-59, exploring the following idea:

Researchers have contended that patterns of age-related decline are not necessarily due to age, but rather to disuse, or declining practice.

In other words, everyone knows we get slower (and weaker and feebler and so on) as we get older. But how much of this is directly due to aging, and how much is simply because we’re less active than we were in our salad days?

Young and his co-authors provide a nice survey of the literature, reviewing a series of studies suggesting that the declines in “expert performance” that we take for granted in many fields aren’t necessarily physical inevitabilities. The average golfer, for instance, might expect to slow by about 0.5% per year between the ages of 51 and 60 — but a study of still-active professional golfers found that their performance dropped only half as quickly, possibly because they were still practicing as hard as ever. Even the skills of aging concert pianists turn out to depend more on how much they’re still practicing than just their age (though the same isn’t true of amateur pianists, who were never practicing that hard in the first place).

So, as you might expect from all this preamble, the new study found similar results for masters runners. Current training volume and training volume over the previous five years were better at predicting race performance than age alone. On the surface, this may be seem obvious — training makes you faster, no matter how old you are. But the implications are more subtle. In our society, it’s not unusual for 18-year-olds to spend a couple of hours each day shooting hoops in the schoolyard; and it’s not unusual for 45-year-olds to spend 60 or more hours a week sitting in front of a computer. If, in some giant cosmic experiment, those societal patterns were reversed, how much of what we consider to be the “natural decline of aging” would we still see?