Whether it’s drinking more water, exercising daily, or curbing your snooze-button tendency, making a healthy habit actually stick can be tough. But there is one way help a new routine feel like second nature: Add it into your morning ritual.

In a small new study of 48 people, researchers had half of the participants complete a 15-minute stretch every morning after waking up and the other half do the same before bed. While the night group didn’t make stretching habitual until the 154th day, the morning group had it down pat on the 105th.

The study authors believe the morning group was more successful because the behavior was “perceived as less difficult, more satisfying, or more easily cued in the morning than in the evening,” but there’s also another possible explanation: the participants’ cortisol levels, AKA the stress hormone. And since the stats were checked daily, authors were able to determine the levels were typically higher in the morning than at night.

“If you decide to start your day with a glass of water, use a cue to remind you. After a while, the cue won’t be necessary.” —Marion Fournier, lead study author

The combination of higher morning cortisol levels and successful morning habits isn’t a coincidence: Research has shown cortisol affects learning and memory and also plays a role in helping people learn faster, which could explain why the morning group made stretching a habit quicker than the night group. And it’s easy to get similar results for yourself.

“If you decide to start your day with a glass of water, use a cue—a note on the kitchen table you’ll see when you wake up, for example—to remind you at the beginning,” lead author Marion Fournier, a lecturer at the Université Nice Sophia Antipolis in France, told Time. “After a while, the cue won’t be necessary.”

No matter what you’re attempting to make routine, repeating it bright and early every day might help it stick once and for all.

This gut health habit should be part of your fall reset. Or if you’re looking to upgrade your matcha habit, try Dirty Lemon’s new drink.