I love Calories... but how many do I need?

I am trying to calc how many calories I should be consuming so I dont waste away… too quickly.

So far I have this figured out.

  1. BMR= Basal metabolic rate
  2. TEF= thermogenic effect of food
  3. Activity=the amount of calories burned in workouts (from HR monitor)
  4. TEE=Total energy expenditure

TEE=(BMRxfactor)+(Activity)+(TEF)

I will calculate my BMR with the Mifflin-St. Jeor formula. Then I read that I have to multiply by a activity factor (ie. 1.3-very light, 1.6-light, ect.). I sit at a desk all day so should i use the very light factor and then just follow the formula above, or do i select a higher factor and not add the calories from HR monitor for workouts?

How the hell do I calc the TEF?

Hope some of you super smart science/biology guys can help me out.

very light base + activity. If you want to include the TEF then subtract 5%. everything else is overthinking it, especially for a triathlete.