A MET (the resting level of O₂ consumption for humans)
A MET stands for "Metabolic Equivalent" and is considered the VO₂ required for one kilogram of living tissue at rest to survive. This has been determined to be 3.5 mL · kg^-1·min^-1.

From the above resting standard, we can classify various levels of exertion by a equivalent number of METs. The greater the level of exertion above rest, the greater the number of METs an activity will be.

For Example:
12 min per mile=8.7 METs
6 min per mile=16.3 METs
Archery=3 to 4 METs

By knowing the MET value, many other quantities and or values can be calculated (e.g., VO₂ at rest, approximate VO₂ for a given activity, number of calories used for a given activity, etc.)

Converting to MET's based on percentage of  VO_2max/peak  VS    %VO_2Reserve  

• When we take a percentage of a person's VO_2max/peak to determine exertion intensity, we can either calculate straight from VO_2max/peak (does not consider resting VO₂) or we can take it from the VO_2Reserve (VO₂R) (does consider resting VO₂). This is the same as using a direct percentage of Max Heart Rate (does not consider resting heart rate) for exertion intensity versus using the Heart Rate Reserve method (does consider resting heart rate).
  • ***Whatever method you use to calculate exertion intensity, that should be the value you use when converting to METs and Kcals in your exercise prescription (ExRx).***
     
• Example: Converting METs using VO_2max/peak  and   VO_2Reserve for a person that has a VO_2max/peak of 50 mL · kg^-1·min^-1 that is prescribed to exert at 50% intensity.
  •  VO_2max/peak  Conversion: METs = (VO₂ /3.5) * % Intensity (ACSM, 10th edition, p. 150, Box 6.2); ((50/3.5)*.5 = 7.14 METs
  • VO_2Reserve (VO₂R) Conversion: First to get VO₂R = ((50-3.5)*.5)+3.5 = 26.75 mL· kg^-1·min^-1 Then to get METs,  26.75/3.5 = 7.64 METs
  • **As you see above, using different methods results to slightly different MET values**

Formula:  VO₂R  to  METS 

• METs = VO₂R divided by 3.5 mL · kg^-1·min^-1
  • Example: A person is exerting at a VO₂ of 35 mL · kg^-1·min^-1. What are the METs?  METs = 35 mL· kg^-1·min^-1 / 3.5 mL· kg^-1·min^-1 results in 10 METs

Formula:  Absolute VO₂R  to  METS

• METs = Absolute VO₂R divided by a person's body weight, which converts it to an relative VO₂R and is divided again by 3.5 mL · kg^-1·min^-1
  • Example: A person has an Absolute VO₂ of 3500 mL·min^-1 and weighs 100 Kg (220 lbs.). What are the METs?  METs = (3500/100) / 3.5 = 10 METs

What is your approximate Absolute VO₂ requirements at Rest? Your kcals at rest?
To figure your VO₂ at rest do the following:

• Convert your body weight by dividing your pounds by the conversion factor for kilograms (2.2)
• Multiple your kg weight (weight in kg) by the value of a MET (3.5 ml · kg^-1·min-1). The result is an approximate value of your Absolute VO₂ in (mL) O₂ at rest.
  

How would you figure your approximate Resting Level kcal requirement if you know that 200 mL O₂ releases approximately 1 kcal energy?

Can you figure weight lost at resting level if you know that 3500 kcal is equivalent to one pound of weight (assume fat weight)?