A tried-and-true breathing exercise has its roots in ancient yoga practice but was first popularized in the Western world by integrative medicine specialist Dr. Andrew Weil in 2015. It’s a simple technique called the “relaxing breath.” By inhaling through your nose to the count of 4, holding that breath for 7 counts, and then exhaling through your mouth to the count of 8, you activate the parasympathetic nervous system responsible for resting and digesting.

According to CNN, this measured breathing not only sets your body up for rest, it also reduces the risk for cardiovascular disease and Type 2 diabetes and improves pulmonary function. Researchers in Thailand published a study in July that found that the 4-7-8 breathing technique helps reduce heart rate and blood pressure.

“There is some evidence that 4-7-8 breathing helps reduce anxious, depressive, and insomniac symptoms when comparing pre- and post-intervention,” says Joshua Tal, a New York state-based clinical psychologist.  Tal adds that there are no large-scale studies specifically on the effects of 4-7-8 breathing on insomnia, but by reducing anxiety, you increase your likelihood of achieving sound sleep.

“The 4-7-8 breathing exercise is utterly simple, takes almost no time, requires no equipment and can be done anywhere,” says Dr. Weil on his website. “Sit with your back straight while learning the exercise. Place the tip of your tongue against the ridge of tissue just behind your upper front teeth and keep it there for the entire exercise.”

Here’s how it’s done:

• Exhale completely through your mouth, making a whooshing sound.

• Close your mouth and inhale quietly through your nose for a mental count of four.

• Hold your breath for a count of seven.

• Exhale completely through your mouth making a whooshing sound to a count of eight.

Repeat this breath cycle three more times for a total of four cycles.

Weil adds that if you have trouble holding your breath for seven counts, you can speed up the count for a while until your body adjusts.

“This breathing exercise is a natural tranquilizer for the nervous system,” he explains. “Unlike tranquilizing drugs, which are often effective when you first take them but then lose their power over time, this exercise is subtle when you first try it, but gains in power with repetition and practice. Do it at least twice a day.”

Watch a video of Dr. Weil demonstrating the 4-7-8 breath. The more you practice it, the better you will become, say experts. Your body and mind will be able to incorporate this useful technique into your toolbox of methods to reduce stress and anxiety daily before they can wreak havoc with your sleep cycles.