Musicians' Hearts at Work
Playing music is physically demanding, but that demand depends on the piece, the part, the instrument, and the interpretation. Averaging each musician's heart rate while their part was active or tacet over several pieces reveals differences between instruments and roles.

Heart rate changes in some players is more dramatic because of their instrument. Wind players heart rates rise and fall quickly as air pressure in the lungs affects cardiac activity. This effect of playing shows clearly when we align measurements between performances, seeing how motion, breathing, and heart rate change with the music, note by note.

Group Heart Rate with the Music
Despite these individual differences, music can also drive a common trajectory of cardiac activity. Kjempevisesl?tten by Saevarud has been performed in many of the Bodies on Concert experiments, and the powerful building of orchestral sound is matched by the increasing heart rates (decrease in IBI) across sections of the orchestra and sometimes the audience.

Musicians' Coordination and Togetherness
Musicians move to make sound, to show expression to the audience, and to communicate with each other. It is interesting that coordination between players is reduced during the more intense half of this piece, suggesting that we see greater diversity in movement styles when players are being more overtly expressive.

Here, one of our interview participants talks about the bodily energy and excitement that comes from playing as an integrated part of the orchestra at a moment where the music requires intensity and synchrony.
I'm pretty sure my heart was beating faster. I think… Because it's so physical, this expression. You're doing a very fast motion... On one hand, you're going with the wave. But on the other hand… It's almost leaving you breathless. Because it's fast music. You know where it goes. So there's no doubt. You just have to catch up with it. You can't be behind it. I guess it's like a very big excitement. Like a rush. A rush of… I don't think it's stress. I don't think I was stressed. I was excited. Yeah, a rush of excitement.
Some of our participants pointed to the special feeling of integration that comes from playing in unison with the rest of the orchestra—here, a musician described playing the Finale of the William Tell Overture.
It's a nice feeling… that you are doing exactly the same style… It's hitting the string together with others, even if your voice would not be significant, but it's a feeling of unity within the whole string group.
There is a sense of togetherness in the orchestra even when not everyone is playing. Our interview participants describe appreciating the beauty of their colleagues' solos, sometimes sitting back, listening, and relaxing, and other times feeling a bodily connection to the music and the soloist. Here, a participant talks about connecting through breathing with a soloist:
When I hear my colleagues playing something like a solo, there is a certain sense of, like, you follow what they are doing with your breathing. Sometimes you tend to like want to breathe with the breathing that they're doing because you kind of put yourself in what they are playing, even though you're not playing yourself.
What role does the conductor play in the orchestra? Our interviews with conductors show that they feel their role changing from moment to moment—now they are leading, now they are stepping back, now they are passing cues between instrument sections. One of our conductor participants, who acknowledged that the orchestra could play entirely without a conductor, summed up the experience:
I think I'm not important here, but I'm still integrated with the orchestra.
Audience Motion

Audiences react in different ways, even to the same music.
Measured with an overhead infrared camera, an audience of school children moved more by default. In two concerts, they started more active during the quiet start of Kjempevisesl?tten and then became more still for the dramatic, bombastic ending. In contrast, a mixed audience of adults and younger children (family concert) started relatively still and maintained that average amount of motion until the applause at the end.
When measured with accelerometers on the body, it is easy to capture small changes in motion or stillness. Adult audience members attending the KORK 2024 concert behaved typically for classical music concerts. However, they showed an increase in motion to the end of Kjempevisesl?tten both times it was performed in full.

Breathing in the concert hall
How people breathe during concerts also depends on what they do, but the timing and depth show us a piece of how musicians coordinate and audience members react.
