Why the 21-day habit is a lie


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The alarm goes off. 5am. It's cold and I can hear it raining outside. My shoes are laid out, I know where my running gear is, but a decision still needs to be made. To get up, or not to get up, that is the question.

If I hadn't made a morning habit, I'd probably ignore the call of the road.

But I have, so without thinking much I hop up and start to put on my gear.

the 21 day habit is a lie

This is the power of habitual behaviours. They hack our brain and help us prioritise one behaviour over another. If I am in the habit of ignoring my alarm, then I will. If I am in the habit of getting up, then I will.

Habits are hard to break and even harder to form - that is what makes them so special. All our rational mind can do is create narratives justifying the behaviours that our habits dictate.

In many respects, the living of a good life can be linked to the ability to form new good habits and break old bad ones.

It is this instinctive knowledge that has led to the popular myth that it only takes 21 days to form a habit. This is simply not true. It has taken me months of regular practice to get into the habit of morning exercise, and it seems that my experience is pretty normal.

The idea that it takes around 21 days to form a habit is not based on any science.

The genesis of the myth is often attributed to a book published in 1960 by plastic surgeon Maxwell Maltz, who noticed that his patients took about 21 days to adapt to their new body after reconstructive surgery. The 21-day theory is actually about adapting to change forced upon you, rather than creating new habits that are voluntary.

Many recent studies show that the speed of habit formation changes according to how hard the activity is, whether there is social pressure to conform, and whether there is any pleasure found in alternative behaviours that would undermine the desired habit.

In a 2009 study by Lally et al, published in the European Journal of Social Psychology, researchers showed it took about 66 days for behaviours, such as a daily 15-minute run, to become a habit.

Another study conducted by psychologists at the California Institute of Technology analysed the habits of gym-goers and healthcare workers.

They found that the timeline for developing a habit varies widely depending on the person and the task, and there is no set timeline for forming a habit. However, they did discover that it takes an average of about six months to form a gym habit, while it only takes a few weeks for healthcare workers to develop the habit of frequent hand washing.

Turns out that a new year's fitness resolution is going to be a mental battle for most, come winter when the cold, dark, wet weather screams at us to hit the snooze button and remain in the warm bed.

So don't beat yourself up if, after a few months, you're still struggling to form a good habit. It takes time, but it will happen. If you stay the course, you will find good habits are one of life's true joys and a doorway to success.

Tips for creating successful habits

  • Start slow and ease in. If you want to run, start by walking and slowly build up to a run. If you want to quit junk food, gradually cut out fast food for a few days at a time instead of cutting it out all at once. Feel successful in the small steps and you'll be more likely to reach the big ones.
  • Keep the end game in mind. It could be a fitness, financial or relationship goal. Knowing what we want to achieve is a good motivator when things get tough.
  • Don't beat yourself up. Breaking the plan for a day doesn't stop the habit forming. Don't throw it all away simply because you missed a day.
  • Find a friend. We are herd animals. Sharing the experience creates shared accountability and a sense of belonging that is linked to the behaviour.
  • Design your environment for success. If you want to lose weight, it's probably best not to have treats in the fridge.

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Phil Slade is a behavioural economist and psychologist and the author of Going Ape S#!t! and founder of Decida. He works across digital innovation, strategy and cognitive bias. Phil holds a Bachelor of Psychology from The University of Queensland and a Master of Organisational Psychology from Griffith University.