Tuesday, December 15, 2009

How fast do running and swimming records drop with age?

Yale economist and marathon runner Ray Fair has analyzed record data in running and swimming to estimate the rate at which our ability drops with age.

As you see below, records decline at a relatively steady rate between the ages of 35 and 70-75, then the rate of decline picks up rapidly.

We see that distance running and swimming drop off faster than sprinting, and Fair notes that women drop off a bit faster than men. Chess declines are much slower than the physical activities.

Fair has calculated age factors like those graphed above for men running and high jumping, men and women swimming, and chess. For example, here are the age factors for short races -- 100, 200 and 400 meters -- by men:

Age factor1.

Using the table, you can see that if, for example, you ran 100 meters in 12 seconds at age 35, Fair would predict that you would have slowed to 1.23 x 12 = 14.8 seconds by age 70. (His tables use age 35 as a reference point).

If you have a time from an age other than 35, you can compute a predicted time using the ratio of the the two age factors. For example, if you ran a race in 20 seconds at age 50, you would expect it to take 20 x 1.23 / 1.09 = 22.6 seconds at age 70.

You can download a spreadsheet with all of Fair's age factors or use his online calculators to make your own estimates:This paints kind of a grim picture for me -- I am just turning 70 -- but there are a few "outs." For one, I spend more time weight lifting than running or swimming. I wonder what the age factors for weight lifting records are? A second possibility sounds like wishful thinking, but maybe record holders decline faster than the rest of us lesser athletes. Testosterone is another variable. To what extent are these results a function of diminished testosterone levels, and can testosterone supplementation slow the decline? (We have to talk about the efficacy and safety of testosterone supplementation in a later post).