The month of December, with parties, mince pies and Baileys galore, can play havoc with your weight and fitness – but Christmas diets always seem particularly joyless.
Fortunately, there is another way to fend off the excesses of the festive season – the Advent Streak!
No, this doesn't mean taking all your clothes off and streaking under the Christmas lights... this is the growing trend of doing a 'running streak' throughout December, running every day of the month, finishing with a brisk run on Christmas Day, obviously.
Running every day might sound like a bit of a chore, but it's got to be better than eating rice cakes every day just so that you can have a couple of extra roasties with your Christmas lunch. And it makes your Advent calendar chocolate taste extra yummy.
Sarah, who did the streak last year, said, "It means guilt-free Christmas eating! What could be better than that? Last year I did 5k every day, went to loads of Christmas parties and didn't gain any weight. Genius."
Adrienne, otherwise known as @runtoeatcake, agrees.
"Because I dislike running in the dark, cold, wet weather, I know it would be too easy for me to say in my warm, soft, comfy bed in the mornings, so to keep me motivated I've decided to do the Advent Run Streak.
"I will also benefit from extra cake credits which is always a bonus!" she added.
There are a number of online groups set up to help motivate runners – the Run Mummy Run Facebook group has an event set up where people can share their experiences of running at least a mile a day, the Advent Running group has more than 1,300 members on Facebook and Twitter, while @runnersadvent on Twitter is also gathering a community together to run for 25 minutes each day.
@runnersadvent said, "It's a healthy spin on an unhealthy time of year, a great challenge and way to bring the running community together."
This group is raising money for United Through Sport, an international sports development charity – if you miss a day of the challenge, you donate £2.50 to the charity. Which gives you a get-out clause if you overdo it at the office Christmas party and can't drag yourself out of bed the following day.
Many seasoned runners are signing up for the challenge in order to keep their motivation going through the tough, dark, winter days.
"I'm doing it to try to find my running mojo," said Shona. "After training for two marathons this year I'm lacking in motivation to run. I'm training for Brighton Marathon which is in April so I'm hoping the run streak will make me stronger."
Claire, who set up the Run Mummy Run Advent event, is also preparing for a marathon.
"I'm doing it to keep my running mojo going during the winter and hopefully to build up my speed again before embarking on marathon training again after Christmas," she told us. "Also, it's great to do something together with the Run Mummy Run community and support each other. And it's totally inclusive, whether you're a new or experienced runner."
But what about the dangers of getting injured? Isn't running every day going to put strain on your joints? Well, a mile a day isn't really very far... and you shouldn't be going hell for leather on every single run. Adrienne (@runtoeatcake) says the key is to treat some runs as 'recovery runs' – in other words, taking it as easy as possible.
"I try to be clever with the timings of my runs to maximise the rest time, so some days I will run very early and the next day in the evening. I will also vary my pace and distance, using an easy pace short run for recovery," she says.
New runners might even want to try walking on some of their days – anything is better than sitting on the couch eating Quality Street, after all.
And if you want to round off your Advent Streak with a bang, there are a number of parkruns happening all over the country on Christmas Day. To check out whether there's one happening in your area, go to ParkRun.org.
If there isn't, I can certainly recommend running on Christmas Day anyway. On the final day of my own Advent Streak last year, I went for a beautiful morning run, and watched the Christmas Day sun rise up over the canal. It was a moment of peace in a hectic, exciting day. Then I went home, cracked open the wine and started cooking the roast. With my smug pants on. Bliss.