Changing Lifestyles, Changing Habits
Pretty much everybody knows that exercise is one of the
components of a heart healthy lifestyle. But it’s not always easy to know
whether you’re doing enough. Is the walk you take every evening after work
making your heart work enough? What about the quick workout at the gym you do
several times a week?
The U.S. Surgeon General recommends that people get at
least 30 minutes of moderate-intensity exercise on most days of the week. You
don’t have to do it all at once. It’s okay to break it up into increments of 10
or 15 minutes at a time.
There are different ways to measure the intensity of your
exercise. Some are simple, others are more complex.
For example, there’s the “talk test,” which is a simple
measurement. Using this method, if you’re exercising at a light intensity, you
should be able to sing. At a moderate rate, you should be able to talk
comfortably while engaging in the activity. If you feel too out of breath to
talk while you’re exercising, that activity would be considered vigorous.
A more detailed way to assess your exercise level is to
measure “metabolic equivalents,” or METs. An MET is a unit that estimates the
amount of oxygen your body uses when you exercise.
It takes about one MET to sit quietly, read, talk on the
telephone, etc. As you increase your activity level, your MET rises as well. In
general, activities that use 3 to 6 METS would be considered moderate-intensity.
This requires 3 to 6 times the amount of energy you expend while sitting
quietly. An activity that requires 6 METs or more would be considered vigorous.
Most up-to-date gym machines have MET indicators on them.
If you work out at a gym, take a look next time to see whether there’s one on
the equipment you use.
Intensity level changes with age
The amount of METs you use when you exercise changes as you
get older. For example, activities that had an MET of, say, 3 when you were 40
may have an MET of 5 now.
Sample activities and their METs
Activities that would use 3 to 6 METs, indicating moderate
- Walking at a moderate or brisk pace, at 3 to 4.5 mile
- Cycling at about 5 to 9 miles per hour, on a relatively
- Weight training and body building using free weights
- Inline skating and roller skating at a leisurely pace
- Coaching a sport—for children or adults
- Dancing at a relaxed pace
- Swimming for recreation
- Light gardening and yard work—raking, trimming, bagging
Activities that would use 6 METs or more include:
- Jogging or running
- Wheeling your wheelchair
- Walking briskly up a hill
- Bicycling more than 10 miles per hour or up a steep hill
- Karate, judo, tae kwon do
- Jumping rope
- Circuit weight training
- Professional, energetic dancing
- Heavy gardening—quick, heavy shoveling; swinging an ax
What should your goal be?
The best thing to do is talk with your doctor to figure out
how intense your exercise should be.
As we said above, the Surgeon General recommends 30 minutes
of moderate-intensity exercise most days of the week. But research also
indicates that it’s a good idea to push yourself sometimes to use more METs than
would be considered moderate. Ratchet your workout up a little; make yourself
work harder. You don’t have to exercise at an intense level for your whole
workout, but sustaining a higher intensity for a little bit of time is a good
way to go.
The Centers for
Disease Control and Prevention; The New England Journal of Medicine, 4
August 2005; Harvard School of Public Health; U.S. Department of health and