Does it take 21 or 66 days for a habit to form?

There's a myth that says it takes 21 days for something you do daily to become automatic.

Sometimes you hear 66 days instead, and that number comes from a study by Philippa Lally et al. carried out on 96 volunteers, which... didn't say that at all.

Each of these volunteers had one action of varying complexity to perform every day, always health related (eating a piece of fruit, going for a walk...). Every volunteer had to repeat the same action daily throughout the study.

The study found that, broadly speaking, across all actions and all volunteers, it took an average of 66 days for an action to become automatic.

But, and it's a big but - I cannot lie, what's really interesting is the range of results: it took anywhere between 18 and 254 (two hundred and fifty four!) days, depending on the action. A simple action like drinking a glass of water became routine far more quickly than a complex one like... exercising.

The other fascinating thing this study revealed is that missing a day had no impact whatsoever on the habit forming.

So what this tells us is that yes, it takes time for a movement routine to become a habit, to become anchored in us. Don't expect that September motivation boost that has you running three times a week to transform you profoundly. Not instantly, anyway.

But it also tells us that what matters is carrying on. Not letting yourself get discouraged because you missed a day, because that missed day doesn't stop the habit from forming.

What does stop it are the stories we tell ourselves the moment we miss a day. We feel guilty, we decide we've given up again, that we're incapable of being disciplined, so what's the point?

If we persevere, if we go back to it the next day, that's how it eventually becomes automatic. That's how we build our identity as "someone who exercises regularly".

And that's why I'll always push you towards the "a little, often" strategy. Missing a 10 minute session today is incredibly easy to make up for tomorrow.

Now tell me: Which habit would you like to make automatic?

Much love,

Clem

PS: The 21-day claim comes from a plastic surgeon in the 1960s, who observed that his patients took roughly 21 days to adjust psychologically to changes in their appearance after surgery. He extrapolated that "it requires a minimum of about 21 days" for any mental image to dissolve and a new one to take its place... and everyone in the self-help world decided that the same goes for any habits 🥴 

Yoga with Clem

La Madeleine, France

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