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May 2003
Previous issues
Each month we offer a new article by Kitty Consolo, Ph.D. Kitty is a veteran runner and exercise physiologist. She has been running and racing since 1975, and has won over 400 road races ranging from the mile to the marathon and went to the first women's Olympic marathon trails in 1984. Kitty has a PR of 2:42.46 for the marathon and 35:02 for the 10km, She now enjoys shorter races and masters running.
Enjoy, and please let us know your thoughts about the Runner's Corner!
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Aging and
Performance
The number of runners continuing to work out and
compete after college and well into their later years has greatly
increased in the last 20 years. This is a quite interesting
phenomenon since research has shown that both humans and lower animals
tend to decrease their physical activity as they grow older. While
world and national records show that our physical prime in running
tends to be in our late 20s and early 30s, those who continue to run
as they age reap many benefits that their sedentary counterparts do
not. Below are some areas in which your continued running can give
you an edge over those in your age group who are sedentary.
V02 max
Studies have been done comparing older athletes
and less active people of the same age in regard to their V02 max
which is a term exercise physiologists use to describe how well one
can maximally utilize oxygen. The normal rate of decline of this
maximal use of oxygen is about 10% per decade beginning in the late
teens for women and mid-20s for men. As a result, one experiences a
decrease in cardiorespiratory capacity and running performance.
However, in studies which compared trained runners with untrained,
particularly if the runners maintained close to the same intensity
(volume was decreased) during workouts, their decline in V02 max was
only .14% per year of 1.4% per decade. And of course we can find
individual exceptions such as Clarence DeMar, who WON his 7th
Boston Marathon at age 42 and was 78th out of 153 runners
at the age of 65. His last race in 1957 at age 68 was a 15km which
he ran despite advanced intestinal cancer and a colostomy. Thus is we
use, we have less change of losing our fitness and being able to
continue our sport.
Cardiovascular changes and aging
Related to V02max are cardiovascular changes that
occur with aging. Our maximal heart rate, which is the number of
beats our heart can go per minute, decreases slightly less than one
beat per year as we age. A good estimate of your max heart rate is to
take 220 – your current age. The amount of blood your heart can eject
per beat, or its stroke volume also decrease with age as does ones
cardiac output, which is the amount of blood the heart can put out in
a minute. However, in those who continue to run, there is less loss
of cardiac output and stroke volume thus indicating cardiovascular
changes are again minimized by those older athletes who continue to
train.
Adapting to high altitude and aging
For
those who like to run in the high mountains or altitude, aging does
not appear to reduce our capacity to run at high altitude. We already
slow regardless of age to the higher altitude and aging does not
appear to add much to this. In regard to the extreme high altitude
specialists, mountain climbers, there are many stories of people age
70-90 who continue to climb. Some research suggests that younger
people are even more prone to altitude sickness (which can lead to
death if not treated and person does not descend) and that aging might
provide some protection against symptoms of acute altitude sickness.
Adapting to heat and aging
One area in which one must exercise more caution
as one ages is in regard to the ability to exercise in the heat.
Aging reduces our sweat production which is one of our best ways to
reduce heat particularly if evaporation can take place. However, on
hot humid days, of which Ohio has several, all runners are at risk for
heat problems, because on such days, little sweat is evaporated
thereby minimizing the amount of cooling that can occur. Frequent
water intake, such as 8 ounces of fluid every 20 minutes and stopping
if signs of heat illness occur such as goose bumps, dizziness,
lightheadedness, cramps and fatigue are the best way for both the
older and younger runner to prevent heat illness.
Body Fat and aging
In regard to one’s body fat, those who maintain
their running will have significantly lower body fat when compared to
their non-active same age counterparts. However, even the most
trained older athletes have been found to have more body fat than
trained younger athletes. Thus those of you struggling to be as lean
as you might have been in your 20s might find comfort in the fact that
there appears to be some aging component that adds to body fat even if
you stay active. These body fat levels however for both the trained
young and older athletes are well within healthy levels.
Health benefits
Those of you who continue to run later in life
will also realize great health benefits. Risk of heart disease is
greatly decreased as compared to your sedentary counterparts. Cancer
risk is also decreased as one study in Great Britain found a general
52% decrease of all cancers in men who ran 3 times a week and a study
in Sweden found women who ran 3 or more hours a week had a 70% less
risk of developing breast cancer. Research collected from alumni at
Harvard University and Aerobic Center in Dallas suggests that there is
a decrease in mortality rate and an increase in about 2 years of
longevity in people who remain physically active throughout live.
In
Closing
In closing, as we age, we can expect to find decreases
in our running performance due to decreases in our V02 max,
cardiorespiratory factors, body fat and heat tolerance, but these
decreases are much less than our sedentary counterparts. The closer
one can maintain intensity (rather than total mileage) close to one’s
younger years, the less decline one should experience. And the best
pay off of all is that we can live healthier and longer. So keep on
running, and may you all live long and prosper! See you at the races!
Kitty | 
