TempoLife › Features › Video explainers › what-is-a-calorie
What a calorie actually is
By the end the viewer can say what a calorie measures, and why the same word describes a biscuit and a flight of stairs.
There are no videos here yet, and this page does not pretend otherwise. TempoLife has published no explainer videos, so nothing on this surface is watchable and there is no player anywhere on it. What is published is the script library: the full storyboard for each explainer, ready to shoot.
The hook
“You have counted them for years. Can you say what one is?”
First four seconds. It states the surprise outright rather than promising one, because a promise is a reason to scroll and a surprise is a reason to stay.
Why this topic is worth 75 seconds
Everything else on this site assumes the viewer knows what the unit means, and most people do not — they know calories are the thing to have fewer of. A definition changes how the rest lands: energy in food and energy spent by a body are the same quantity in the same unit, which is the only reason the arithmetic works at all.
It is also the script that earns the right to show a big number. A kilogram of body fat holds roughly the energy of a full day and a half of eating, and seeing that figure once explains why weight moves slowly no matter what the packet on the shelf promises.
The storyboard
| Time | On screen | Voiceover | Visual |
|---|---|---|---|
| 0:00–0:04 | What is a calorie? | You have counted them for years. Can you say what one is? | Close on a food label, finger tracing to the kcal line. |
| 0:04–0:14 | A unit of energy | A calorie is a unit of energy. Not a nutrient, not a chemical — a measurement, like a metre or a litre. One kilocalorie is the energy it takes to warm a kilogram of water by one degree. | Kettle on a hob, thermometer rising. Simple, physical. |
| 0:14–0:26 | Same unit, both directions | The useful part is that the same unit measures both sides. The energy in the food, and the energy your body spends being alive and moving around. That is the only reason you can subtract one from the other. | Split screen: plate on the left, a person climbing stairs on the right, one number bridging them. |
| 0:26–0:42 | Energy density is the story | What surprises people is how differently foods carry it. Pure sugar and a raw apple are not in the same league per hundred grams, and neither is a bag of crisps. | Three bowls, equal volume, with their figures counting up on screen. |
| 0:42–0:58 | A kilogram of fat | Stored body fat is dense. One kilogram of it holds roughly the energy of a day and a half of normal eating — which is why a week of small changes moves the scale slowly and a week of big claims does not move it at all. | The kilogram figure lands full-frame and holds for two seconds. |
| 0:58–1:10 | The other side of the ledger | And spending it takes time. Brisk walking costs a handful of calories a minute, so the minutes needed to work off a snack are longer than anyone wants them to be. | Walking figure with a minute counter ticking. |
| 1:10–1:15 | Where to check | Every food page on TempoLife shows the number, and where it came from. | End card: /calories. |
Read it as a script
The voiceover column, in order, is the whole piece:
You have counted them for years. Can you say what one is?
A calorie is a unit of energy. Not a nutrient, not a chemical — a measurement, like a metre or a litre. One kilocalorie is the energy it takes to warm a kilogram of water by one degree.
The useful part is that the same unit measures both sides. The energy in the food, and the energy your body spends being alive and moving around. That is the only reason you can subtract one from the other.
What surprises people is how differently foods carry it. Pure sugar and a raw apple are not in the same league per hundred grams, and neither is a bag of crisps.
Stored body fat is dense. One kilogram of it holds roughly the energy of a day and a half of normal eating — which is why a week of small changes moves the scale slowly and a week of big claims does not move it at all.
And spending it takes time. Brisk walking costs a handful of calories a minute, so the minutes needed to work off a snack are longer than anyone wants them to be.
Every food page on TempoLife shows the number, and where it came from.
Every number this script shows
The energy-density beat and the kilogram-of-fat beat.
| What appears on screen | Value | Where it comes from |
|---|---|---|
| Sugar, per 100 g | 387 kcal | TempoLife food database (USDA FoodData Central SR Legacy) |
| Apple, per 100 g | 52 kcal | TempoLife food database (USDA FoodData Central SR Legacy) |
| Potato chips, per 100 g | 532 kcal | TempoLife food database (USDA FoodData Central SR Legacy) |
| Energy in 1 kg of body fat | 7 700 kcal | Standard figure, ~7,700 kcal/kg |
| Brisk walking at 75 kg | 5.6 kcal/min | data/site/exercises.php (2011 Compendium of Physical Activities) |
| Minutes of brisk walking for 500 kcal | 89 min | Computed on this page |
Nothing in the storyboard above quotes a figure directly. The beats refer to numbers and this table supplies them, so a script written months ago cannot go stale against its own data.
Production notes
- Vertical 1080x1920, 75 seconds. Hard cut on every beat boundary — no transitions.
- Numbers appear as large type over the footage; they are the visual, not a decoration on it.
- Burned-in captions throughout: most viewing is muted, and every figure in this script is a number that has to be readable.
- No stock footage of laboratories or DNA. Kitchen, stairs, pavement.
Closing card
Look up any food at tempolife.app/calories
General information, not medical advice. These scripts describe averages across populations; nothing in them is a diagnosis or a treatment recommendation.
Source: Figures computed from the TempoLife food database (USDA FoodData Central SR Legacy) and the 2011 Compendium of Physical Activities · checked 2026-09-02
What the script points at
Other scripts
BMR vs TDEE, in one worked example
Two numbers, one of them nearly useless on its own.
The one column people read wrong on a label
This packet says 130 calories. It contains a lot more than 130.
Ranking foods by protein per 100 calories
Everyone knows which foods have protein. Almost nobody knows what it costs.
Why the scale jumps two kilos overnight
You did not gain two kilos of fat while you slept. It is not physically possible.
Where 10,000 steps came from
Ten thousand steps is a marketing target. It came from a pedometer name.
Walking vs running: per minute and per kilometre
Running burns more than walking. Per kilometre, less than you think.
All scripts · Listen to the guides
The numbers, for your own day
This script shows averages. TempoLife records yours: meals, steps, sleep and weight in one place.