The NBA's 71-day offseason from the end of The Finals on October 11th to the start of the 20-21 season on December 22nd is the shortest offseason in the history of the NBA, NFL, NHL or MLB.

There is concern among health officials around the NBA for how to prepare for the NBA's 72-game regular season.

"It's going to be especially challenging to not only get ready to play Dec. 22 or whatever but to maintain that for a period of four or five months," said one head athletic trainer of a Western Conference team, who, like others, spoke on the condition of anonymity.

"This is going to be another period of unchartered territory. As unchartered as the [Orlando] bubble was [this summer], this is the bubble times three or four or five [because we're] trying to extend it to that period of time with a minimal ramp-up."

League officials have noted that a shorter offseason is typical during years in which there is an Olympics or other national team competitions. 

Eight teams haven't played a competitive game since March, which may be a bigger issue than the teams not getting enough rest.

Said one official involved in player health, "I would be more worried about the teams that haven't played in over eight months, honestly, as opposed to [other 22] teams."