Christmas, New Year, aperitifs, fondue nights, dessert buffets — during this time of year, most people see their calorie intake noticeably increase. Studies show that adults gain an average of 0.5 to 1 kilogram over the holidays. What makes this weight gain tricky is how persistent it tends to be. The problem usually isn’t that one evening of indulgence — it’s what happens in the days before and after. A small daily surplus that quietly adds up over several weeks.
How much more do we eat during the holidays?
During the festive season, many people eat more than usual. Various studies paint a similar picture: the typical weight gain ranges from 0.5 to 1 kilogram. Translated into energy, that’s an excess of approximately 3,500 to 7,000 kilocalories over the entire holiday period.
Breaking this down to individual days gives a clearer view:
Over several weeks, the daily surplus typically ranges from 80 to 200 kilocalories. A familiar mix — an extra glass of wine, another piece of chocolate, slightly larger portions at meals, or the cookies that just belong to the season.
On the actual holiday celebrations, calorie intake can skyrocket. A traditional holiday meal can easily reach 1.5 to 3 times the usual daily intake. Appetizer, main course, dessert, maybe a cheese platter, plus snacks and alcohol — and just like that, a single day can total 3,000 to 6,000 kilocalories.
The simple running rule: As many calories as kilos per kilometer
To estimate how running can offset holiday indulgences, a simple endurance training rule helps:
For every kilometer run, the body burns approximately as many kilocalories as the person weighs in kilograms.
So, a person weighing 70 kg burns about 70 kcal per kilometer. Whether the run is easy or moderately fast doesn’t drastically affect the calories burned per kilometer. Speed mainly influences how long the run takes.
Example calculation: What does this mean during the holiday season?
Let’s take a 70 kg person.
If the average daily surplus during the holidays is about 100 kcal, the calculation is simple:
100 kcal ÷ 70 kcal/km = approx. 1.4 km – that’s around 10 minutes of easy running.
If you add about 1.5 km of running most days during the holidays, you can effectively balance out this small daily surplus. For example, by adding a short loop on the way home from training, or spontaneously turning an 8 km run into a 9.5 km run.
Looking at the total gain of about 0.5 kg body weight, we’re talking about roughly 3,500 extra kilocalories. At 70 kcal/km, that equates to about 50 extra kilometers.
Those 50 km don’t need to be run all at once. Spread over six weeks around Christmas and New Year, that’s about 8 to 9 additional kilometers per week. In practice, this could mean adding about 3 km to three regular runs.
The big holiday feast: Why you shouldn’t try to “run off” Christmas dinner
It gets even more interesting when focusing on one big festive meal.
Let’s say you consume around 2,000 kcal more than usual in a single day. Again using the 70 kg example:
2,000 kcal ÷ 70 kcal/km = about 29 km.
In other words, to burn off just that one meal, you’d have to run a full 29 km – on top of your regular daily activity and training.
This is not a call for punishment runs.
Instead, it highlights how unrealistic it is to try and compensate for one indulgent meal with a single workout.
Much smarter is to look at the overall average:
Be a bit more mindful on the days before and after, return to normal portions, and avoid overcompensating out of guilt.
What does this mean in practice?
The holiday season often comes with more free time – a great opportunity to sneak in a few extra kilometers.
At the same time, small mindful adjustments in eating habits can go a long way. You don’t need extreme restrictions or an ascetic December to avoid weight gain.
A practical approach could look like this:
- Enjoy the holiday meal without guilt
- In the days before and after, bring portion sizes back to normal
- Reduce liquid calories (alcohol, juice, soda) – they’re energy-dense but not filling
- Choose snacks with a little more awareness
- Increase your running volume slightly
But be careful: Only add extra kilometers if your body also gets enough recovery. More volume is only effective if balanced with rest – especially during a busy season.