If your massage clients book regular sessions, they will probably continue to do so even when under lots of stress.

Investigators at the University of Southern California found that in times of stress, people lean on established routines, including healthy ones. This means that mindless behavior doesn’t just lead to shopping sprees and binge-eating; it can also cause us to stick with behaviors that are good for us.

Across five experiments, the researchers provide a new take on the established idea that we have finite resources for self-regulation, meaning it’s harder to take control of our actions when we’re already stressed or tired.

They found we are just as likely to default to positive habits, such as eating a healthy breakfast, getting massage or going to the gym, as we are to self-sabotage.

This research shows that lack of control doesn’t automatically mean indulging in unhealthy behaviors; it’s the underlying routine that matters, for better or worse.

The study will be published in the June issue of the Journal of Personality and Social Psychology, published by the American Psychological Association.

For example, in one experiment Wood and her co-investigators followed students for a semester, including during exams. They found that during testing periods, when students were stressed and sleep-deprived, they were even more likely to stick to old habits. It was as if they didn’t have the energy to do something new, Wood explains.

Students who ate unhealthy breakfasts during the semester – such as pastries or doughnuts – ate even more of the junk food during exams. But the same was true of oatmeal eaters: those in the habit of eating a healthy breakfast were also more likely to stick to routine and ate especially well in the morning when under pressure.

Similarly, students who had a habit of reading the editorial pages in the newspaper everyday during the semester were more likely to perform this habit during exams – even when they were limited in time. And regular gym-goers were even more likely to go to the gym when stressed.

“You might expect that, when students were stressed and had little time, they wouldn’t read the paper at all, but instead they fell back on their reading habits,” Wood says. “Habits don’t require much willpower and thought and deliberation.”

Wood continues: “So, the central question for behavior change efforts should be, how can you form healthy, productive habits? What we know about habit formation is that you want to make the behavior easy to perform, so that people repeat it often and it becomes part of their daily routine.”