This means that the battery is discharged down to 10.5 volts over a 20 hour period while the total actual amp-hours that it supplies are measured. Sometimes ratings at the 6 hour rate and 100 hour rate are also given for comparison and for different applications.
Pool meets are usually no more than 4 hours, but beach meets last about 7 hours. It depends how many events are in the meet. And then if it is a really big meet (like a tournament kind of) it can last days. Hope that helps.
1.1) Individual Non-Interscholastic Competition Dates. A swimming and diving athlete who has not participated for the school in a swim-. ming and diving contest during the current season must cease non-interscholastic. competition six weeks (42 days) prior to the Monday of the week of the State Swim-.