For some reason once I have placed text on a circle path and then adjust the path, the text gets distorted instead of being uniformed.
You're selecting the path and the text, they are treated as one combined object so they both distort as a unit. You need to use the direct select tool (aka the white arrow) to just select the path and then distort that without distorting the text. You won't get handles to freehand distort the path, but you can use the
Object > Transform tools to achieve what you want. You can also grab and move individual parts or points of the path if that works better for you.