Notice
Null-gravity combat exercises were a part of standard Starfleet training.
James T. Kirk and Spock conducted null-gravity combat exercises together aboard the USS Enterprise a week prior to going on the Vedala expedition.
They later employed some of their null-gravity combat training during the expedition to combat Tchar, after he activated a gravity neutralizer in the Skorr temple, forcing those on the expedition to "fly and fight as a Skorr." (TAS: "The Jihad")