NEAT - non-exercise activity thermogenesis, "the energy expended for everything we do that is not sleeping, eating or sports-like exercise. It ranges from the energy expended walking to work, typing, performing yard work, undertaking agricultural tasks and fidgeting. Even trivial physical activities increase metabolic rate substantially and it is the cumulative impact of a multitude of exothermic actions that culminate in an individual's daily NEAT."
How much does NEAT add to daily calorie burn? The academic consensus: much more than exercise does. Lyle McDonald's own research leads him to the same conclusion:
"The amount of exercise that is or can usually be done is actually fairly trivial compared to the rest of the day.
"That is, the hour someone might spend engaged in exercise is still pretty small compared to what's happening the other 23 hours of the day."
Lyle has covered NEAT at length.
This brings us to a question we should ask ourselves when fat loss is the goal: which is arguably more important, NEAT or exercise?