Running out the clock
In American football, each quarter of a game is measured with a 15-minute game clock, or 12-minute clock in many high school football codes and the German Football League. A team in possession of the lead and the ball will attempt to use up as much of the game clock as possible in order to bring the game to an end more quickly, thus denying the opposition another chance on offense.
United Indoor Football
A game consisted of four 15-minute quarters with a halftime intermission 20 minutes in length. The clock typically only stopped for time-outs, penalties, injuries, and official clarifications. Further stoppages occurred for incomplete passes and out of bounds during the final 90 seconds of the second and fourth quarters. A mandatory official's time-out, called a promotional timeout, was assessed after the first and third quarters and is 90 seconds in duration. Another mandatory official's time-out, called a warning period, was assessed with 90 seconds to play at the end of each half. The game could also be stopped for further promotional time-outs but not exceed 90 seconds per league rules.