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Question the values

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I would question the values given in the table, that "desk-work" = 1.8 and "strolling" = 2.0. There should be a much greater difference. Sitting work should be 1.0 or maybe 1.2 and standing work should be around 2. I came to this article to find the difference in METs between sitting work and standing work, but I don't believe the listing. Baruchatta (talk) 16:01, 28 July 2010 (UTC)[reply]


Met-minutes Unclear

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If a single MET is the resting metabolic rate, and a MET-minute is (duration of activity in minutes)*(METs of the activity), then doesn't everyone, by definition, acquire about 10,080 MET-minutes per week? This is well above the targets given in the article, and makes me think that either there are some additional facts that need to be included or the MET-minute concept is vapid. —Preceding unsigned comment added by 156.56.148.221 (talk) 01:04, 7 June 2010 (UTC)[reply]

I agree. The article Heart failure says that the recommended minimum by U.S. guidelines is 500 MET-minutes/week. There are 10,080 minutes in a week, so what's the problem? Or let's say that resting doesn't count. So you can do 400 minutes (6 hours and 40 minutes) of 1.25 MET activity! Everybody does that. Something doesn't make sense. Eric Kvaalen (talk) 09:41, 13 February 2018 (UTC)[reply]

Cooper Points

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I would be particularly interested to read a discussion of the difference between METs/mile in a eg training run versus 'Cooper Points' for the same activity. See Talk Page for Kenneth H. Cooper. In brief, the higher METs for 6 minute miling over 10 minute miling are nearly compensated for by the reduced time to cover the distance :-). But the Cooper points on a per mile basis differ by nearly a factor of 2 (IIRC) (Numbers - Cooper says 3 miles at 30 to 36 minutes is 11 points, and if done in 20 to 24 minutes that rises to 20 points.

Now the METs for 12 minute miling is 8.5 and for 6 minute miling rises to 16. So per mile, it's nearly a constant...)

Surrogate formula cpm/kg

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Some exercise machines estimate METs based on the formula: cpm/kg. [1] This convenient non-individualized approximation is often used, including in scientific literature. "No work requires only “basal metabolism,” or about 3.5 mL O2/kg/minute, also known as 1 MET." [2] "One MET is defined as the energy it takes to sit quietly. For the average adult, this is about one calorie per every 2.2 pounds of body weight per hour someone who weighs 160 pounds would burn approximately 70 calories an hour while sitting or sleeping." [3]

These simple surrogate formulas are widely used. Please do not censor this information from the article. Please add details about how good or bad this approximation is, how much reality varies by plus or minus for who under what conditions.-69.87.204.9 14:39, 12 July 2007 (UTC)[reply]

SI Units Required

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Please bring this article up to date and into the 2oth century (!!) by using SI units for energy and power. These are the Joule (J) and Watt (W). Expressing power in terms of kcal/hr seems absolutely bizarre to me, and to have to make this request in the 21st century is equally so. This is surely Wikki at its worst. — Preceding unsigned comment added by 82.46.12.25 (talk) 07:47, 21 June 2011 (UTC)[reply]

In general, I would agree with you but not here. If you want to understand how the MET came into being then you have to examine the history of exercise science and exercise physiology. Much was carried out in France and in Germany, but subsequently much was also carried out in the USA and in the UK.
The calorie is actually a very useful unit of energy because it is defined as the amount of energy needed to raise the temperature of one gramme of pure water by one degree Celsius. Admittedly, this creates problems of its own because the energy needed depends upon the temperature and the pressure, so we end up with slightly different definitions of the calorie, for example the 15 degree Celsius calorie.
Nevertheless, as an easily remembered and visualised unit, the calorie like the inch, the foot, the yard, the fathom, the chain, the furlong and the acre all remain invaluable.
In exercise science, one calorie is a bit small. The kilocalorie is more useful. Hence, historically one MET was defined as the thermal energy expenditure of one kilocalorie of energy per kilogram of body mass per hour.
Intriguingly, as a rough rule of thumb this happens to approximate to the typical basal metabolic rate (BMR) or resting metabolic rate (RMR), measured in kilocalories per kilogramme per hour, of the human subjects used in the early experiments. This was a healthy, adult human male of standard body mass (ie 70 kg as it was back in most western countries in the early decades of the last century), in his twenties or thirties, and of normal body fat and leanness. 58.165.123.47 (talk) 21:13, 18 February 2013 (UTC)[reply]

Multiple issues

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I've tagged the article for the following reasons:

1. The article's introduction is too technical and/or becomes too technical too quickly. This is a wiki style issue.

2. There is almost no information in the article on the origins of METs

3. There is almost no information in the article on the derivation of the tables

4. Citations in the article are inadequate.

5. The criticism section (Limitations on the ...etc), although much needed, requires additional citations.

The bulk of the article appears to rely extensively in one source (Ainsworth) and at least one of the references is incorrect e.g the ANSI/ASHRAE Standard 55 does not specifically deal with Metabolic rate, but "defines the range of indoor thermal environmental conditions acceptable to a majority of occupants".

IMO the article needs attention from a medical expert. There are other issues with the style of the article but imo the above issues are the most pressing.

LookingGlass (talk) 13:15, 18 September 2013 (UTC)[reply]

Confusing and incomplete

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The textual context to the definition is inaccurate, incomplete, and misleading. The article first states the MET has units (power)/(kg). I would guess that the (power) is either: the body's output power or the energy burned per unit time. These are different! The definition does not state which to use. Also, the (kg) is not defined. I would guess the (kg) is intended to be body mass, but again, this is not stated. The next sentence says the MET is also defined as (power)/(m^2), where the (m^2) is body surface area. These are two different definitions! There should be a discussion on the differences: "Some authors [...] define a MET as power produced per body mass; other authors [...] define a MET as power produced per body surface area." Or something along those lines. — Preceding unsigned comment added by 128.135.186.216 (talk) 19:25, 30 April 2014 (UTC)[reply]

moved this comment to the end as per wiki protocol. It seems to add to my remarks above. Should it be indented? LookingGlass (talk) 18:57, 1 May 2014 (UTC)[reply]

Metabolic Equivalency Task

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The heading of Wikipedia should read "MET (Metabolic Equivalency Task)" This would reduce a lot of confusion. Most trainers and fitness experts and healthcare researchers refer to "METs", as a basis for measuring workout intensity. Another factor which creates confusion is the exercises that can vary in intensity, such as running, unless other specific parameters are met, like miles per hour and the height and weight of the individual. — Preceding unsigned comment added by 2602:30A:C0B4:EE30:E8F9:1668:FFAD:CED0 (talk) 17:07, 4 November 2014 (UTC)[reply]

METs and WATTs

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Please add discussion and information about converting between METs and Watts. Many common exercise machines now use both those units. Conversion tables and formulas? -71.174.175.150 (talk) 23:32, 28 November 2014 (UTC)[reply]

specifying volume of oxygen

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I've noticed that the oxygen consumed is specified in millilitres. That is not specific enough. Especially temperature and pressure should be specified. Otherwise I'd guess 293K & 100kPa, but that is not common knowledge. Tothphu (talk) 05:14, 3 June 2015 (UTC)[reply]

American usage of Calories (upper case "C") in MET calculations can be confusing

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Common Source of Confusion about KCal in MET formula

It might be useful to explain that common usage of the term Calorie (spelled with upper case "C") in American literature to express energy consumed by exercise actually means kilcalories, or in technical abbreviation, Kcal. This is unfortunate. Also, it might be useful to explain how one converts from VO2 measurements in mL O2/Kg/min to Kcal/kg/h. Deriving energy from glucose provides a good starting point. The heat of reaction (enthalpy) of glucose oxidation is about 677 Kcal/mole and it takes 6 moles of oxygen per mole of glucose. Each mole of oxygen equals 22.4 L at standard temperature and pressure. Therefore, 1 L of oxygen is 0.0447 moles, enough to oxidize 1/6 of 0.0447 moles of glucose or 0.00744 moles. It means that energy of glucose expended by 1 L of oxygen equates to 0.00744 mole x 677 Kcal/mole or 4.96 Kcal, or about 5 Kcal/L O2. To convert 3.5 mL O2 to Kcal, divide by 1,000 mL/L and multiply by 5 Kcal/L. To convert from min to h, multiply by 60. The rounded off result is 1 Kcal/Kg/h. Clean Jordan Lake (talk) 22:41, 6 February 2017 (UTC)[reply]

Additional Linked Information

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This section should be used to add links to additional information about this subject.

Free article about METS and Activities

The above is a dead link... IiKkEe (talk) 20:17, 30 November 2018 (UTC)[reply]

Inconsistent handling of power and METs

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The section which lists how many METs for a task is incorrect where "power" is given. For example, the number of METs using a stationary bicycle at 50 or 100 watts depends on the weight (mass ...) of the individual. I weight about 82kg, so 100 watts is close to 1.2 w/kg. A lighter rider -- say 50kg -- would be producing 2.0 w/kg, which is more METs. And obviously a heavier rider would be producing fewer. The examples should provide the weight of the example riders, with a footnote explaining how to translate to their own weight for an individual reading the article. Tall Girl (talk) 19:47, 15 March 2018 (UTC)[reply]

The information in this article is, IMHO, sound. I don't claim to be a medical expert, but that is not the type of person who is best suited for editing this information. The medical industry has, in general, about a week of health and nutrition education. Hence, a GP is of little value when questioned about the subject (although they will provide an opinion).

What's truly missing in this article, as already pointed out, is "layman" terminology to extrapolate what's documented. In other words, it needs to have layman terminology "added" to all of the technical information "within" the technical content.

I've been in the health, nutrition, diet and exercise industry for more than 40 years. My brother wrote the "Nutrition Desk Reference" (Robert H. Garrison, Jr.). Were he still alive I would confer with him to provide text that "anybody" could understand.

What I would like to offer is this. First, 100% of Calorie expenditure calculations - regardless of the formula - is an "estimate". It's not possible to calculate Calorie expenditure per-person without going to a lab and get hooked up to a lot of technology that monitors that one person. Therefore, whatever methods are used to "calculate" Calorie expenditure (and yes, Calorie or Calories with a capital "C" is proper - lower case means something other than the Calories to which we are referring) are simply a method of giving someone an "idea" of how much effort they are putting forth when they are doing..."anything".

We burn Calories 24/7/365. Or, we burn Calories as long as we are living and breathing. Weight, age, body composition, fitness level, daily diet, amount of sleep and the amount of oxygen a person intakes are all factors that effect the Calorie expenditure of any "single" person. So to specify that "X" number of Calories are burned for a "?" pound person is impossible. The only method of calculation is to estimate. Therefore, the MET is an estimate that can be used to "closely estimate" how many Calories "you" burn.

The reason I found this article today, and why I'm interjecting, is because I'm re-developing my own site - GarrisonBody.com - with a new look "and" trying to streamline the content so the general public not only understands, but doesn't have to be a health and nutrition expert to know what the funk I'm trying to say. I'm also trying to see the calculators I have in my site could be made any more accurate.

Please take a look at GarrisonBody.com/gbnew/ if you'd like to see where I'm going with the new site. And I'm only mentioning my site because - I'm saddled with the same situation. How to take technical data and "dumb-it-down" so that "anybody" can make sense of the information. It's not easy.

I'd be happy to consult with Wikipedia on this article to help resolve at least "some" of the issues. Please contact me using my account information so that I can get an alert via E-mail. I don't log in but every few years, although I do use Wikipedia a lot. And yes, I just donated in January.

Let me know if I can help. LTCreations (talk) 20:01, 7 March 2019 (UTC)[reply]

Valiant misplaced sympathies

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For the record, my sympathies are 2 parts the reader, and 1 part the MOS. I just made edits that serve the reader 100% better, but the MOS 20% less well. Certain sticklers might not approve. Revise or revert at will; I'm done with this dog. — MaxEnt 00:16, 20 March 2023 (UTC)[reply]

By some miracle, I refrained from adding an assertion about the use of MET⋅hours/weakling of PT in boot camp. — MaxEnt 01:31, 20 March 2023 (UTC)[reply]