"They" (you know, that anonymous group of people who say and do a lot of things), say it takes 21 days to make or break a habit.
Yes, it may take several weeks to develop a new habit. And some things will take a while to work out of our system. But some habits are altogether too easy to break.
I have been working out several times a week for more than two years. A few muscle pulls have sidelined me temporarily, but I fought my way back to 3-5 weekly workouts as soon as I could.
And then this summer hit. Moving into a new house and everything that went with it consumed most of May. Daily workouts became a question instead of a statement. Then school let out and mornings became unstructured and un-regimented. My five-morning-a-week workout routine became hit-or-miss (and that's a charitable description.)
So I'm not sure "they" are right. It didn't take 21 days to break me of daily workouts. In fact, it was really easy to let my routine slip away.
I'm determined to get back to working out several days a week, and get my running distances back to a respectable length. But I'm not sure this will ever become a true habit that I would have to work hard to break.