Recent Recommendations for Healthy Adults

The next logical question is what kinds of activity are recommended? The
answer lies in a newly published article in Circulation
which is the Journal of the American Heart Association, entitled, “Physical
Activity and Public Health: Update Recommendation for Adults From the American
College of Sports Medicine and the American Heart Association.”(1)
For all healthy adults aged 18 to 65 years of age the recommendation is a
minimum of moderate intensity aerobic (endurance) physical activity for a
minimum of 30 minutes on five days each week or vigorous intensity aerobic
physical activity for a minimum of 20 minutes on three days each week. A common
way to estimate energy expenditure for a given activity and understand what is
meant by these intensity designations is to use the concept of METs or
metabolic equivalents. When someone is sitting quietly, they expend 1 MET. The
moderate intensity activities expend from 3.0 to 6.0 METs and the vigorous
activities exceed 6 METs. In terms of METs, the minimum goal is to expend 450
to 750 METs per week in moderate intensity activities, vigorous intensity
activities or a combination of the two. A person can meet the minimum by a
combination of moderate and vigorous intensity activity. Moderate intensity
activity is generally equal to a brisk walk and noticeably increases the
heart rate. Vigorous intensity aerobic activity causes rapid breathing and a
substantial increase in the heart rate. Jogging is one example of vigorous
intensity activity. The table below gives some examples of common activities
and classifies them in these categories.

MET   Equivalents of Common Physical Activities From Ainsworth, et al. 2000

Light < 3.0   METS

Moderate 3.0 –   6.0 METs

Vigorous >   6.0 METs

Walking

Walking

Walking, Jogging & Running
Walking   slowly = 2.0 Walking   3.0 mph = 3.3 Walking   at a very, very brisk pace (4.5 mph) = 6.3
Walking   at a very brisk pace (4.0 mph) = 5.0 Walking/hiking   at moderate pace and grade with no or light pack (<10 lb.) = 7.0
Hiking   at steep grade & pack 10-42 lb = 7.5-9.0
Jogging   at 5 mph = 8.0
Jogging   at 6 mph = 10.0
Running   at 7 mph = 11.50

Household & Occupation

Household & Occupation

Household & Occupation
Sitting   – using computer, work at desk using hand tools = 1.5 Cleaning   – heavy; washing windows, car, clean garage = 3.0 Shoveling   sand, coal, etc. – 7.0
Standing   performing light work such as making bed, washing dishes, ironing, preparing   food or store clerk = 2.0-2.5 Sweeping   floors or carpet, vacuuming, mopping = 3.0-3.5 Carrying   heavy loads such as bricks = 7.5
Carpentry   – general = 3.6 Heavy   farming such as bailing hay = 8.0
Carrying   & stacking wood = 5.5 Shoveling, digging ditches = 8.5
Mowing lawn – walk power mower = 5.5
*MET values can vary substantially from person to person during swimming as a result of different strokes & skill levels.

The recommendation also indicates that bouts of moderate intensity aerobic activity at least 10 minutes in duration can count towards the 30 minute recommendation. Furthermore, because of the dose response relation of physical activity and health, people who wish to further reduce their risks for chronic diseases may do so by exceeding the minimum recommendations for activity. From the standpoint of weight loss, 60-90 minutes of moderate intensity physical activity daily seems to be necessary to maintain a weight loss of 30-50 lbs. The recommendation also calls for every adult to perform activities that maintain muscular strength or endurance at least two non-consecutive days a week. That should include 8-10 exercises involving all major muscle groups. This exercise should include sufficient weights to cause muscle fatigue after 8-12 repetitions of each exercise.

In the next post I’ll talk about exercise and people over the age of 65 or with chronic conditions.

For Your Health – Dr. Bob

Footnotes:
(1) W. L. Haskell, et al. Circulation. 2007;116:1080-1093; originally published online Aug. 1, 2007


More About Pros And Cons

Last time I spoke about listing your pros & cons whenever you are considering changing one of your behaviors, whether it’s smoking, losing weight, or starting an exercise program.  I thought an example might be helpful, so here is such a list regarding following a weight loss program that includes healthier eating and exercise components.  It’s very similar to the one I used after my heart attack and cardiac arrest to help me make the changes necessary to live a healthier life.

Pros Cons
I’ll probably have more energy. I’ll have to limit what I eat.
I’ll look better – slimmer. I’ll have to limit the amount of food I eat – measure my portions.
I’ll have to find time in my daily routine to exercise at least 4-5 times a week.
It will decrease my risk for heart disease. I’ll have to read food labels when I shop.
I’ll feel proud of making such a change.  
It will decrease the strain on my knees.  They probably won’t hurt as much.  

When I first wrote these I used “It would” instead of “It will” and “I’d” instead of”I’ll.”  It may be subtle, but using “will” gives it a more positive tone, a tone of commitment.  As you can see, there are more reasons to start a weight loss program than not.  In addition, the value of the Pros far outweighs the inconvenience and effort represented by the Cons.  In this list the Pros are greater than the Cons in quality as well as in quantity.

In my next post, I’ll talk about listing the barriers to the successful implementation of your plan along with what you’ll do to overcome them. 

For Your Health – Dr. Bob