How long can matches be, and how much can a player play in one day?

Laws of the Game (Under-19 variation): a match lasts 70 minutes at most (two halves of no more than 35 minutes, plus time lost). Extra time is not allowed. In non-international matches the match organizer can shorten matches.

USA Rugby's youth guidance gives these maximums, based on school grade:

Other points from the same guidance:

• Players need at least 1 hour of rest between matches on the same day, and must stay within the daily limit.
• The maximum times include any time used to settle a tie in a knockout match.
• Smaller fields and shorter times are acceptable when circumstances call for them.
• The minimum field size for high school play is 90 x 53 yards.
• When 9th to 12th graders play together, use the 11th/12th grade ("Varsity") limits.

The per-day limits stop players being overextended at tournaments. Under World Rugby's laws and directives, these maximums are required for Under-19 players, not just recommended.