Wednesday, May 11, 2011

METS aren't just a baseball team -

To be honest, my post about metabolic equivalents or METs should wait until tomorrow.  I had what I wanted to say in my mind last night, but when I went to write early this evening, I had to reread the article and do some math in order to fully understand what I wanted to tell you.
The information comes from the current issue of the ACSM's Certified News.  The article is written for professionals with the objective of having them educate their clients.  Hence, it is important and I do want to share the information.
For now, let me just say that an MET is a simpler way to consider caloric expenditure as it relates to VO2 max.  The more oxygen our body demands the more calories we burn. 
METS are assigned to certain activities and the higher they are the more vigorous the activity and the more calories you will burn.  However, you could choose a low MET activity like golf and do it for an hour and burn the same as an activity with double the METS that you do for half an hour. 
(I was actually going to delay this post - but it looks like I am half way there - so let me go on)

Exercise recommendations can be found at this CDC website.  Vigorous activity is considered to be > 6 METs. 
Some METs are as follows:  extremely slow walking (46 minutes per one mile) = 2, walking 15 minute miles (i.e. 4 miles in one hour) = 4, jogging at 11.5 minute miles = 9 and full out running =14.  My 10 minute miles are about 10 MET.  Golf is 3.75 and bicycling can be anywhere from 4 to 16.  Here are two charts that can help you to know the MET of many activities.  The first one will allow you to search the document by entering an activity in the box on top - it saves time.  You will need to know the MET to plug it into the formula that I will be providing.

Now we are all different so try not to base your intake on programs that say if you do a certain activity (say dancing) for an hour you will burn x amount of calories.  Most of those equations are based on 150 pound persons and do not include the exertion level.  Even the formula that I will give you cannot be taken as "fact" because there are many variables or circumstances that can impact an individuals' burn.

The second thing you need to know is how much you weigh - in kilograms.  So go weigh yourself..... if its in pounds, divide by 2.2.
Okay - find your activity and think about how much time you did spend or will spend doing it - such that your MET is the number in the chart multiplied by duration.  If it is an MET of 8 and you are doing the activity for 20 minutes, the MET for the formula is 160.

MET*3.5*WT/200 = ~ calories burned

Let us do my run from yesterday  - it lasted 64 minutes and my pace was just over 10 minutes (10:03) Looking at this chart , my MET is 10:
10 * 64 = 640
640*3.5*43/200= 481.6 calories burned on that run.  [my garmin GPS watch calculated 489 and a web based calculator figured 430.]  The formula I have provided here is from the ACSM document and thus, I trust it most.
Now if the person who did that run weight 150 pounds or 68kg, the outcome would be 761 calories.

Remember all of this because my next post may be about the difference in calories burned and calories consumed - i.e. how much food is 481 calories?  Remember also that you burn calories all day and night - and there really isnt' a way to be 100 percent sure of your day to day caloric needs.

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