When we run in desktop mode, there is a whole-body animation that looks appropriate. In VR mode, our legs are animated as we run, but our arms keep with where our hand controllers are. We run with straight-down arms, which looks unnatural.
Technically, users could fake it by swinging their arms, but it would be next to impossible for them to correctly keep in sync with the legs. And very unlikely that users will choose to do this.
Consider automatically engaging an arm-swinging animation when VR users run.
One caveat, though. Sometimes, you want to override this. Take the HoverDerby game, for instance, where you really want to show people aiming and shooting. My suggestion is to only engage this animation if the user appears to be standing and their arms are down at their sides. If they so much as lift one arm, I would disable it and let their hand controllers take over.