I played 6 years of rugby. I also played high school football. My position, lineman, in football was a pretty non-collision position and I never experienced any

I played 6 years of rugby. I also played high school football. My position, lineman, in football was a pretty non-collision position and I never experienced any concussions. In rugby, every position involves collision. As a backline player most of my job was to run, but there was no way of ever avoiding multiple collisions in a game. Less impactful then football for the reasons you mention, but more frequent. I know for certain that I've had (at-least) a few concussions in rugby. For instance, getting up from a hit and having no idea where you're at for a second, and then feeling the world morph back into you as if it were knocked right out.