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A heart-strengthening
pace: brisk but comfortable |
November 11, 2003
ORLANDO, FL (AHA)
–
The
pace that feels right probably is. When it comes to fitness, a
brisk, comfortable walking pace strengthens the heart,
researchers reported at the American Heart Association’s
Scientific Sessions 2003.
The American Heart Association and other advisory groups
recommend that all Americans regularly participate in
moderate-to-vigorous exercise that boosts the heart rate to more
than 55 percent of its maximum.
“A large segment of the population still believes exercise
must be vigorous, demanding or involve more complicated
activities than walking to adequately raise one’s heart rate.
This perception of ‘no pain, no gain’ can discourage people from
starting to exercise at all,” said lead investigator Kyle
McInnis, Sc.D., professor of exercise science at the University
of Massachusetts in Boston.
The researchers studied 84 obese adults (72 women, 12 men,
average age 41), who were seeking professional advice on a safe
level of exercise.
“These were middle-aged people like many others. They were
between 30 and 100 pounds overweight, with below-average aerobic
endurance, and had been thinking about starting to exercise and
lose some weight,” McInnis said.
At the first visit, researchers measured heart rate and
oxygen use, while the subjects walked on a treadmill with a
gradually increasing steepness until they felt fatigued.
On a different day, the subjects walked one mile on the
treadmill with instructions to maintain a “brisk but
comfortable” pace. Participants completed the walk in an
average of 18.7 minutes, at an average speed of 3.2 miles per
hour.
During the self-paced walk, all the participants achieved the
recommended levels of exercise intensity, based on their
previous heart rate measures. Thirteen were at moderate
intensity (55-69 percent of maximum heart rate), 58 at hard
intensity (70-89 percent) and 13 at very hard intensity (90-100
percent).
“Comparison with the treadmill tests showed that when
participants self-selected a speed that was comfortable but
brisk, their heart rate and level of exertion was in a safe
range but high enough to improve their cardiovascular fitness,”
McInnis said. “You really can get your heart rate up to the
level that your doctor would recommend, and you don’t have to
jog or run to do it.”
McInnis hopes these results encourage sedentary people to
begin exercising.
“Walking is commonly identified as the single most enjoyable
form of recreational exercise. Our study asked whether walking
at a self-selected, comfortable pace is adequate to elicit the
cardiovascular response associated with improved health and
fitness,” he said.
The American Heart Association, the Centers for Disease
Control and Prevention and the American College of Sports
Medicine suggest people walk or perform other moderate-intensity
exercises for at least 30 minutes five days or more a week.
Being able to give simple advice on walking may get more
physicians talking to their patients about the importance of
physical activity. Currently, only about one in three
physicians counsels patients about exercise, McInnis said.
The message is particularly important for the growing segment
of the population that is overweight or obese. Obesity is a
major independent risk factor for heart disease. Most obese
persons have one or more additional risk factors, such as high
blood pressure, high cholesterol or insulin resistance.
“Increasing physical activity is key to reducing these
risks. Even if weight stays the same – and physical exercise is
a big help in reducing excess weight – physical activity can
improve blood pressure, blood glucose and cholesterol levels,
and significantly lower the risk of death and disability from
heart disease,” McInnis said.
Co-authors are Justin Fiutem, M.S.; Heather Williams, B.S.;
Barry Franklin, Ph.D.; and James Rippe, M.D. |
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