Is Walking Enough?
Better Step Lively
Nov. 13, 2000 -- Legs striding, arms pumping, I'm hustling down
a long corridor at the Cooper Institute of Aerobics Research in Dallas,
alongside exercise scientist Andrea Dunn, PhD. Her studies have helped make
walking more than just a way to get from here to there; she and her colleagues
have elevated it to a respectable form of exercise.
Today, Dunn has agreed to show me just how brisk a walk must be
to count as a workout. I'm hoping that in the process she'll also help settle a
growing debate in the field of exercise research: How hard and how long do you
need to work out to stay healthy? The answer is still controversial. But new
research is beginning to provide a clearer picture.
Brisk walking gained the status of exercise after a landmark
1989 Cooper Institute study came to a surprising finding: that people who were
only moderately fit were significantly less likely to die of heart disease than
those who never got off the couch. True, people who were super fit had the
lowest death rates. But all their extra work gained them only a modest
advantage -- 10% to 15% -- over the moderately fit group. The study, which
followed some 13,000 men and women for more than eight years, was published in
the Nov. 3, 1989, issue of the Journal of the American Medical