I love this because regardless of wether or not it improves speech, it does improve self image which does tend to personally balance out the negative effects that my non-fluent speech can cause. I also recall seeing a study somewhat recently that they detected less blood flow in the portion of our brains that are responsible for our cognitive speech. I also recently had a theory that improving cardiovascular health (by being active and running) could have benefits to people who stutter. Just a theory and haven’t had any results yet but just some food for thought!