Biology Forums - Study Force

Hi all!

I have great interest in this topic as a woodwind player and teacher.

I was wondering if humans are able to control the amount of air they breathe out per-breath without changing the speed of the air they breathe out.
In other words, can we independently control both the speed of the air that we breathe out, and the volume-per-breath?

Because, logically, a higher air speed breathing out means you breathe out more. But when playing a wind instrument, both the amount of air you breathe out and its speed influence factors such as pitch, tuning and sound volume. So I was wondering whether we can control these (partly) independently (naturally or after practice).

Example if it's unclear:
Say you breathe out 500 ml of air every breath, taking 5 seconds to breathe out.
That's 100 ml/s.
In rest, this breath travels at 6 m/s.
If you breathe out forcefully, you breathe out 200 ml/s and the breath speed is 12 m/s.

Can we increase or decrease the 100 ml/s of breath WITHOUT changing the air speed of 6 m/s (as much)?
Conversely, can we change the air speed of 6 m/s WITHOUT changing the volume (as much)?

The same volume of air would need to be spread out more, so the only way would be to increase the size of one's mouth so that the air can be more dispersed.

So if I understand correctly, only from breath, we cannot adjust volume WITHOUT changing air speed? I'm talking about the volume and air speed before it leaves your lips

Yes, the two are connected, because if you breath out really fast (whilst maintaining output diameter, since we're taking before leaving your lips), you're expelling the air out quicker. Using S = d/t, rearranging speed * time = distance, you're see that the distance travelled depends on the speed.