High school pitchers are to be limited in the number of game pitches they can deliver within a certain amount of time. This rule seeks to ensure that a coach, team or player is not tempted to overdo it, resulting in a pitcher doing physical damage to his pitching arm. State associations can make their own regulations, but each state following the NFHS rules must have such regulations protecting pitchers. Umpires must make sure they know what the rule is for their state.
For purposes of this rule, an ambidextrous pitcher is considered one pitcher. All pitches that an ambidextrous pitcher delivers in a game go toward his pitch count. It does not matter what arm he uses. When he reaches the limit, he must exit and wait the prescribed amount of time.