Nutrition

NEAT: the hidden calorie burn nobody programmes for.

By Luigi · 5 min read

A one-hour session with me burns a few hundred calories. The walking, standing, fidgeting and general moving-about you do across the other 23 hours can easily burn more than that — and it's the part almost nobody tracks or plans for. It's called non-exercise activity thermogenesis, or NEAT, and it quietly decides a lot of fat-loss outcomes that get blamed on diet or training instead.

What NEAT actually covers

NEAT is every calorie you burn that isn't sleeping, eating, or deliberate exercise: walking to the station, standing at your desk, cooking, cleaning, fidgeting, taking the stairs. A review published in a major clinical journal found NEAT varies enormously between individuals — by as much as 2,000 calories a day between a very sedentary person and a very active-in-daily-life one, even before either of them sets foot in a gym^[1]. That's a bigger range than most people's entire training-day calorie burn.

The study that makes the point sharply

In a controlled overfeeding experiment, researchers fed volunteers 1,000 extra calories a day for eight weeks and measured exactly where the surplus went. The amount of fat gained varied enormously between individuals — and most of that difference was explained by how much each person's NEAT increased or stayed flat in response to the extra food, not by differences in formal exercise, which was unchanged throughout^[2]. Some people unconsciously moved more when overfed and gained very little fat. Others barely changed their daily movement and gained substantially more. Their training didn't change — their spontaneous daily activity did, without them trying to.

Why this seems to be mostly involuntary

A follow-up study measured how much time people spent sitting versus standing or moving throughout the day and found obese and lean individuals differed by around two hours of daily sitting time — a gap that persisted even after the obese participants lost weight and the lean participants gained it, suggesting posture and movement habits are more biologically driven than consciously chosen^[3]. That's a genuinely humbling finding: some of this isn't just willpower or laziness, it may be closer to a built-in tendency. Worth knowing, not worth using as an excuse to stop paying attention to it.

Why this matters more now than it used to

A more recent, independent review focused specifically on the modern office environment found that the shift toward desk-based, screen-heavy work has quietly removed a large chunk of NEAT that used to be built into daily life by default, and that deliberate interventions — standing desks, walking meetings, short movement breaks — can meaningfully claw some of it back^[4]. The practical implication lines up with the older data: NEAT isn't fixed. It responds to your environment and your habits, even if there's a biological floor and ceiling to how far it moves.

What I actually tell clients

• Your gym session is a small slice of your daily burn. For most people, NEAT outweighs formal exercise as a share of total calories burned in a day.
• Track steps or general movement, not just workouts. If fat loss has stalled despite training and eating being "right," daily activity outside the gym is the first place I look.
• Watch for the quiet shutdown during a hard diet. People in a deficit often unconsciously move less — fidgeting less, sitting more — which can eat into the deficit without anyone noticing or deciding to do it.
• Small daily changes add up more reliably than an extra gym session. An extra 2,000–3,000 steps most days is often more sustainable, and can be worth more over a week, than squeezing in one more workout.