Twenty-four young, healthy test subjects lay quietly in a university lab, listening to carefully chosen music through headphones, as doctors and technicians hovered around them meticulously measuring their vital signs. The study concluded quickly and the subjects returned to their normal everyday lives. But as the researchers began sifting through the data, something new and interesting began to emerge.

We've known for some time that music is a powerful relaxation tool. Music can decrease anxiety levels, lower blood pressure and heart rate, and change stress hormone levels. It affects your respiration, reduces muscle tension, increases endorphin levels, and boosts your immune system. The effect of music is so powerful, hospitals around the world use music to reduce stress in patients waiting for surgery.

Now there's fresh evidence on the power of music to affect our health. Researchers at Italy's University of Pavia recently confirmed that music changes your heart rate, breathing, and blood pressure. But as they analyzed their data, they found something new, something no one had expected to find.

Dr. Bernardi and his colleagues were interested in expanding the use of music to reduce stress in medical patients. Here's how their experiment worked: the docs recorded the vital signs of 24 test volunteers (12 musicians and 12 non-musicians) for five minutes. Then the volunteers listened to six different styles of music in random order. Random two-minute pauses were inserted in each piece of music.

Here's what they found: fast musical tempos increased heart rate, blood pressure and respiration. Slow tempos reduced them. Pretty standard stuff. But then the shocker: the style of music and the volunteers' personal musical preferences made no difference at all. The only thing that mattered was the tempo.

It didn't matter if the music was classical, rap, techno, romantic or an Indian raga. Only one thing made a difference to their cardiovascular systems--whether the music was fast or slow. This means that the music you hear, whether you've chosen it or not, whether you like it or not, is going to affect your health.

There's more: during the silent pauses between musical selections, the test subjects' vital signs returned to normal, in some cases stabilizing at healthier levels than before the music. The researchers say this suggests that listening to any kind of music--fast or slow--could benefit your heart.

Finally, the study found that musicians were more sensitive to the effect than non-musicians. Musicians may have learned to breathe in time to the music, to become more alert during fast passages, and to relax when the music slows down. Whatever the reason, a good prescription for helping maintain your cardiovascular health could be to take music lessons.