I'm currently working on a Training Test App for Android. One of many other features will be a Metronome where you can setup not only cadence, it will also be able to toggle between different breath rhythms like 3:3, 3:2, 2:2 and 2:1. I realize that Jack Daniels wrote a lot about interplay between cadence and breath rhythms.
In this respect I was thinking about Work of Breathing and stumbled across following article:
What impressed me most was the difference between men and women (Figure 5). As far as I interpret Figure 6 correctly this seems to be the mayor limiting fact why women have a disadvantage compared to men.
Would be great if you could share other articles with similar subject which impressed you or talk about your experience.