875—174.2 (90A) Bouts, rounds and rest periods. Each bout shall consist of no more than three rounds. Each round shall be two minutes in length. A rest period of 90 seconds shall be provided between rounds. No contestant shall be permitted to compete in more than three bouts in any 20-hour period.
In national elimination tournaments, when the ability and conditioning of the contestants are assured, the athletics commissioner may authorize two contestants to participate in a fourth bout which determines the championship, provided all bouts are comprised of three 90-second rounds. Under no circumstances will any participant be permitted to compete more minutes in any one 20-hour period than is authorized under the rule allowing three bouts consisting of three two-minute rounds as set forth in this rule.