This rig like from "Community":
https://www.youtube.com/watch?v=EQEiXST_qms
Yes it was like that, but standalone, the computer, I presume was in the base, which was like a platform; about a foot-high puck shape you stood on within the ring which had the treadmill built in.
Edit: I seem to recall it costing 2 lira for a turn.
Sounds like Dactyl Nightmare!
Oh this is cool, it wasn't this one from what I recall (which isn't a lot).
The main things I remember are; it was an FPS, it was indoors/enclosed, the lighting was bad so it was really hard to tell where walls/corners were and it was very, very red.
The controller was sort of ring/oval shaped, I remember basically nothing about the headset other than that it was tethered.
The game was basic, early "3d" (in the gaming sense), low polygon, low resolution, no depth or actual streoscopic, but this was the 90s.
I tried to check it out again on a subsequent visit to Malta but it had of course gone. Real shame, I saw nothing of its kind for decades later.