Experts say the eight-minute-track, called "Weightless", is so effective at inducing sleep it should not be listened to while driving.

Carefully arranged harmonies, rhythms and bass lines help slow the heart rate, reduce blood pressure and lower levels of the stress hormone cortisol.

Manchester trio Marconi Union worked with sound therapists to create the soothing tune, which also slows breathing and reduces brain activity.

The study - commissioned by bubble bath and shower gel firm Radox Spa - found the song was even more relaxing than a massage, walk or cup of tea.

Women were connected to sensors and given challenging puzzles to complete against the clock in order to induce a level of stress.

They were then played different songs as their heart rate, blood pressure, breathing and brain activity were recorded.

Studies found "Weightless" was 11 percent more relaxing than any other song and even made many of the women "drowsy" in the lab.

It induced a 65 percent reduction in overall anxiety and brought them to a level 35 percent lower than their usual resting rates.

The song features guitar, piano and electronic samples of natural soundscapes.

It is pierced throughout by Buddhist-like chants that induce a trance-like state.

Lyz Cooper, founder of the British Academy of Sound Therapy, said Marconi Union had used scientific theory to make the "perfect relaxing song."

She said, "The song makes use of many musical principles that have been shown to individually have a calming effect.

"By combining these elements in the way Marconi Union has created the perfect 'chill-out' song.

"The study actually found this to be the world's most relaxing song."

The Telegraph