No Magic Number for Time It Takes to Form Habits

Putting on your workout clothes and getting to the gym can feel like a slog at first. Eventually, though, you might get in the habit of going to the gym, attending aerobics classes or for a run on the treadmill. A new study from social scientists at Caltech now shows how long it takes to form the gym habit: an average of about six months. The same study also looked at how long it takes health care workers to get in the habit of washing their hands: an average of a few weeks.

The study is the first to use machine learning tools to study habit formation. The researchers, including Anastasia Buyalskaya, a Caltech graduate who is now an assistant professor of marketing at HEC Paris, Colin Camerer, Robert Kirby Professor of Behavioral Economics and director and leadership chair of the T&C Chen Center for Social and Decision Neuroscience and Xiaomin Li, formerly a graduate student and postdoctoral scholar at Caltech, employed machine learning to analyze large data sets of tens of thousands of people who were either swiping their badges to enter their gym or washing their hands during hospital shifts. For the gym research, the researchers partnered with 24 Hour Fitness, and for the hand-washing research, they partnered with a company that used radio frequency identification (RFID) technology to monitor hand-washing in hospitals. The data sets tracked more than 30,000 gymgoers over four years and more than 3,000 hospital workers over nearly 100 shifts.

The study titled “What can machine learning teach us about habit formation? Evidence from exercise and hygiene” was funded by the Behavior Change for Good Initiative, the Ronald and Maxine Linde Institute of Economics and Management Sciences at Caltech, and the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech.

Read more on the TCCI for Neuroscience website