Winter arc rules: the full list of 9 rules to keep for 90 days
In short
There are no official winter arc rules: everyone sets their own. The ones that work are few, can be checked yes or no, and get kept every day. In Winterarc, we went with 9: only water, zero fast food, no phone while eating, the gym 4 times a week, running 2 times a week, 20 minutes outside, one gratitude a day, 10,000 steps and 7 to 8 hours of sleep.
What makes a good rule
A winter arc rule has to pass three tests.
- You can check it yes or no. “Gym 4 times a week” passes. “Work out more” doesn’t.
- It’s up to you. “Lose 5 kilos” describes a result. The rule is what you do every day to get there.
- It lasts 90 days. Picture a Tuesday in November, in the rain, after a bad night’s sleep. If the rule doesn’t survive that Tuesday, adjust it before day 1.
Winterarc’s 9 rules fall into three families: the no-gos (what you stop doing), the grind (what you do) and the machine (what helps your body recover).
Every night, you check them off. The seven daily rules make a full day; Gym and Run count over the week, by Sunday.
The no-gos
Only water.
No soda, no alcohol, no juice.For 90 days, you drink only water: no soda, no alcohol, no juice.
A 330 ml can of soda (about 11 oz) has around 35 g of sugar. The World Health Organization recommends keeping free sugars under 10% of your energy intake, about 50 g a day on 2,000 calories. One can uses up 70% of that. For the WHO, the sugar in fruit juice counts as free sugar too.
Unsweetened coffee and tea? The rule doesn’t say. Decide before day 1 and write it down, so you don’t have to make the call on a tired morning.
Zero fast food.
Fast food can wait until day 91.No chain burgers, tacos, kebabs or delivery pizza for 90 days.
In 2019, a study at the US National Institutes of Health fed 20 adults ultra-processed food for two weeks, then minimally processed food for two weeks, letting them eat as much as they wanted. On the ultra-processed diet, they ate about 500 more calories a day on average and gained weight (Hall et al., Cell Metabolism).
Set your definition before you start: does a homemade burger count? Answer once and for all.
No phone while eating.
You eat. That’s it.During meals, your phone stays face down, or in another room.
A meta-analysis of 24 studies found that eating while distracted makes you eat more during the meal, and even more later in the day (Robinson et al., American Journal of Clinical Nutrition, 2013). Without a screen, you know what you ate, and you stop sooner.
The grind
The gym, 4 times a week.
Not three. Four.Four strength sessions a week, Monday to Sunday. In the app, a counter shows your sessions for the week: 1/4, 2/4…
The World Health Organization recommends muscle-strengthening activity at least 2 days a week for adults. Four sessions let you train every muscle twice a week, with an upper body/lower body split. The full sessions are in our winter arc workout program.
Run, 2 times a week.
Even slowly. Even in the rain.Two runs a week, even slow, even short.
One study followed 55,137 adults for 15 years on average: runners had a 30% lower risk of death from all causes than non-runners, including those who ran 5 to 10 minutes a day at a slow pace (Lee et al., Journal of the American College of Cardiology, 2014).
If you never run, start with 20 minutes, alternating 2 minutes of running and 1 minute of walking.
20 minutes outside.
Every day. Especially in winter.Every day, 20 minutes outdoors, in the morning if you can. Walking to class or to work counts.
Indoors, regular lighting gives you a few hundred lux; outside, even under cloudy skies, daylight gives you several thousand. That light is what resets your body clock, and winter doesn’t give you much of it: in Paris, daylight drops from about 11 hours 45 minutes on October 1 to 8 hours 15 minutes on December 21.
In the app, it’s the rule people keep most often: on days they open Winterarc, users check it off 84 times out of 100.
Gratitude.
One thing, every night.Every night, one good thing from your day. Just one, written in your head, on paper or said out loud.
In 2003, two psychologists asked students to write down, every week, either things they were grateful for or things that annoyed them. After ten weeks, the gratitude group said they were more satisfied with their lives and more optimistic about the week ahead (Emmons and McCullough, Journal of Personality and Social Psychology).
The machine
10,000 steps.
Counted by Apple Health. Nothing to check.10,000 steps a day. If you connect Apple Health, there’s nothing to check: the app reads your step count and checks off the rule for you.
A meta-analysis of 15 studies covering nearly 50,000 adults shows that the risk of death goes down as daily steps go up, until it levels off between 8,000 and 10,000 steps a day in people under 60 (Paluch et al., The Lancet Public Health, 2022). So 10,000 steps sits at the top of the useful range.
It’s the daily rule people check off least often in the app: 52 times out of 100 on active days. The gym and your runs won’t get you there on their own. Get off one stop early, take your calls while walking, walk around the block after dinner.
7 to 8 hours of sleep.
The real secret. Go to bed.At least 7 hours a night. The American Academy of Sleep Medicine and the Sleep Research Society recommend 7 or more hours for adults; for ages 13 to 18, the recommendation goes up to 8 to 10 hours.
Not sleeping enough costs you on the other rules. After two nights of 4 hours, volunteers were 24% hungrier than after two nights of 10 hours, with stronger cravings for sweet and salty food (Spiegel et al., Annals of Internal Medicine, 2004). Fast food gets harder to turn down, and so does the next day’s workout.
To sleep 7.5 hours and get up at 7 a.m., you need to be asleep by 11:30 p.m. The sleep rule is won or lost at night, the moment you put your phone down.
What we left out
Cold showers, waking up at 5 a.m., reading 10 pages, zero social media: these rules are all over TikTok. We didn’t put them in the 9 default rules. Waking up at 5 a.m., for example, clashes with sleep: if you go to bed at 11 p.m., it leaves you 6 hours of sleep. Cold showers and reading are more about personal taste than health.
Nothing stops you from adding them. In Winterarc, the Pro subscription is what lets you edit the rules: remove some, add some, change a goal, from 3 to 12 rules.
Adapting the rules to your situation
- You’re new to the gym. Keep 4 sessions, but short ones: 45 minutes, with light weights for the first two weeks.
- You’re under 18. Bump the sleep rule up to 8 to 10 hours.
- You can’t run. Bad knees, injury, asthma: swap running for cycling, swimming or brisk walking, same number of times a week.
- You want to go further. Add one rule, not five: zero social media after 10 p.m., or 10 pages of reading.
What happens if you miss a rule?
In some challenges, missing a day means starting over: that’s how 75 Hard works. In Winterarc, a missed day costs you the current week, and the winter arc keeps going.
- Every week where you keep all your rules lights your flame.
- Your first missed week is covered by the freeze: your flame survives.
- On the second, the flame goes out, but the winter arc keeps going until day 90.
Water gets special treatment: a day where only water is missing still counts toward the week.
Forgot to check in last night? You can still check off yesterday the next day, and anything you check before 3 a.m. counts for the previous day.
The challenges are compared in winter arc vs 75 Hard vs monk mode.
The rules people keep most in the app
Across the 1,983 days where users checked off at least one rule, up to September 26, 2026, here’s the share of days where each daily rule was kept:
Gym and Run aren’t in this ranking: they’re counted over the week (4 and 2 sessions), not every day. The details are in our study of the first 2,500 winter arcs.
Frequently asked questions
How many rules should a winter arc have?
Between 3 and 9. Any fewer and the challenge has no substance; any more and every day turns into a to-do list you can't keep up for 90 days. Winterarc gives you 9 by default, and the Pro subscription lets you keep anywhere from 3 to 12.
Are the winter arc rules the same for girls and guys?
Yes. The 9 rules don't depend on your gender or your level. What changes from one person to the next is the exercises and the weights at the gym.
Does coffee count in the “only water” rule?
The rule doesn't say. Decide before day 1 whether unsweetened coffee and tea are allowed, and write it down, so you're not making the call on a tired morning.
Can you change your rules during a winter arc?
Better to lock them in on day 1. If a rule really can't be kept, adjust it once, going forward only: in Winterarc, a change never touches the days already behind you.
What's the hardest winter arc rule?
In the app, 10,000 steps is the daily rule people check off least often: gym sessions and runs aren't enough to get there, you also have to walk.