Here's a good look at the conditioning machines from PSU. I believe tech falls are a pretty good indicator, but then too, with some of the pinning machines we have today, they're not scoring as high on the tech Fall list as they could because they are pinning their guys!
A few outliers on the list, and this is just my opinion, but David Taylor was/is a genetic freak amongst genetic freaks! To be a good college wrestler, you would have to be freaky to start with. To be on a list like this, you are waaay out there on the bell shaped curve.
Also, Ruth may have a lower VO2 max than some of the guys below him as his style was just so very relaxed, then all over it, then relaxed again - said another way, more stop and go, less of a grinder, but man could he score when he wanted to!
I remember something about Randy Couture slowing his heartbeat down while increasing his exertion.
http://www.pennstatewrestlingclub.org/history/index.php?view=careertfs