It's interesting to hear that you've noticed a correlation between your breathing exercises and improved fluency in speech. The diaphragm plays a critical role in breathing and speech, as you mentioned, and there is some evidence to suggest that diaphragmatic breathing exercises can be helpful in improving speech fluency for people who stutter. One study found that diaphragmatic breathing exercises combined with speech therapy led to significant improvements in speech fluency for adults who stutter. Another study showed that children who stuttered exhibited decreased diaphragm activity during speech compared to fluent children, suggesting that strengthening the diaphragm through breathing exercises could be beneficial. While more research is needed in this area, it seems that there may be a link between diaphragmatic breathing and speech fluency. It's great that you've found some benefits from these breathing exercises and I would encourage you to continue exploring this further. However, it's important to keep in mind that stuttering is a complex condition and there may be multiple factors that contribute to its manifestation. We talk about this often in the free community I launched a few months ago for professionals who stutter - feel free to join if it interests you! [www.stutterfreely.com](http://www.stutterfreely.com)