Array ( [0] => Array ( [id] => 1 [name] => GT1M [options] => Array ( [icon] => small-device sprite-s-gt3x [product_icon] => medium-device sprite-m-gt3x [code] => Lynx [url] => GT1M ) [description] => [parent] => 1 ) [1] => Array ( [id] => 2 [name] => GT3X [options] => Array ( [icon] => small-device sprite-s-gt3x [product_icon] => medium-device sprite-m-gt3x [code] => Matrix [url] => GT3X ) [description] => [parent] => 1 ) [2] => Array ( [id] => 3 [name] => GT3X+ [options] => Array ( [icon] => small-device sprite-s-gt3xp [product_icon] => medium-device sprite-m-gt3xp [code] => Neo [url] => GT3Xplus ) [description] => [parent] => 1 ) [3] => Array ( [id] => 5 [name] => ActiGo [options] => Array ( [icon] => small-device sprite-s-actigo [product_icon] => medium-device sprite-m-actigo [code] => Morpheus [url] => ActiGo ) [description] => [parent] => 1 ) [4] => Array ( [id] => 6 [name] => ActiTrainer [options] => Array ( [icon] => small-device sprite-s-atr [product_icon] => medium-device sprite-m-atr [code] => Pulsar [url] => ActiTrainer ) [description] => [parent] => 1 ) [5] => Array ( [id] => 17 [name] => ActiSleep+ [options] => Array ( [icon] => small-device sprite-s-asm [product_icon] => medium-device sprite-m-asm [code] => Neo [url] => ActiSleepplus ) [description] => [parent] => 1 ) )
Home >> What METs formulas are used in ActiLife?

What METs formulas are used in ActiLife?

Last Updated: Feb 08, 2012
Views: 949

Two algorithms are used for the MET rate calculations in ActiLife.  
  • The Adult METs formula is used for subjects 18 years and older.  The standard formula for Metabolic Equivalent is used.  Specifically, one MET is defined as 1 kcal/(kg/hour) where kcal is the kcal equivalent as computed from our device counts using the Freedson Equation defined in Calibration of the Computer Science and Applications, Inc. Accelerometer and kg is the subject's weight in kilograms (automatically calculated if lbs are used).  METs are calculated on a per-epoch basis (60 second epochs are required for this tool) and are averaged to obtain hourly MET levels.  
  • The MET formula used for children is METs = 2.757 + (0.0015 x counts per minute) - (0.08957 x age(yr)) - (0.000038 x counts per minute x age(yr).  This formula was taken from Predicitive Validity of Three ActiGraph Energy Expenditure Equations for Children by S. Trost, R. Way, and A. Okely.



This FAQ Applies To:


  • GT1M Device

  • GT3X Device

  • GT3X+ Device

  • ActiTrainer Device

  • ActiLife Software

  • ActiLife6 Software


© 2012 ActiGraph, LLC. All Rights Reserved.