Musical group Marconi Union and Lyz Cooper, the UK's leading therapeutic sound practitioner, have released what they claim is the world's most relaxing music. They contend that the calming effects of "Weightless" are not subjective but are based on scientific evidence. The music was found to cause brainwaves and heart rate to synchronize with the rhythm, reduce blood pressure and lower levels of the stress hormone cortisol. In fact, Scientists played the song to 40 women and found it to be 11% more effective at helping them relax than songs by Enya, Mozart and Coldplay. The eight-minute track is so effective at inducing sleep, motorists have now been warned they should not listen to it while driving.